Efficiency

When transferring energy from one form to another, there will be some energy lost during travel.
Like when you charge your phone using electrical energy and it goes into your phone's battery for chemical energy, it loses some of its energy due to heat. 

There is an equation for calculating useful energy:

Efficiency = Usefull energy output / Total energy input.

But if you are using Power:

Efficiency = Useful power output / Total power input.

Let's take two lamps, one powered by iridescent bulbs and one powered by LEDs, and let's say the iridescent lamp can convert 45 joules to light energy, while the LED can convert 225 joules into light lets figure out how many times more efficiently the LED lamp is compared to the iridescent bulb.

First let's give 300 joules of power to each bulb, and figure out which one is more efficient with the 300 joules. 

So we divide the 45 joules from the iridescent bulb by 300, then we get 0.15, and then we can calculate the LED bulb which is 0.75.
Then we divide the 0.75 by the 0.15 giving us 5, meaning the LED bulb is 5 times more efficient than the iridescent bulb. 
If you mess up the flip of the order of division, you will notice immediately because you will get a value bigger than 100% or a value bigger than 1.

Most of the time, you would want this in either decimal or percentage terms, so to get these numbers, you would need to multiply it by 100.
So, if you wanted to convert 0.15 and 0.75, you would need to multiply it by 100 to get 15% and 75%, then once again we can do 75% / 15% to get 5 again so that we know fully that the LED bulb is 5 times more energy efficient than the iridescent bulb. 
If we were to do the equation wrong, instead of dividing the 225 / 300.
We instead do 300 / 225, we would get 1.33 or 133%, which is impossible as you can't go over 100% in efficiency and not over 1 in decimals because this would be making joules of power which is incorrect because matter cannot be created or destroyed but it can be transferred.

Let's take a new subject, a microwave, with an efficiency of 70% and a total output of 800 watts. Once the equation is: Usefull power output / Total power input, it is 70% / 100% which is 0.7. So to get the useful power output we have to once again multiply the 0.7 by the power input of 800 watts.

So we multiply 0.7 * 800, and we get 560watts, as you know all devices leave some sort of waste when they are using energy, like when you use a electronic device some of the chemical energy and lose some energy in the form of heat.
But for things like electronic heaters, the "wasted energy" is then turned intoT

Stem Cells

Stem cells are very important, they are mainly Adult Stem Cells and Embryonic Stem cells.

There are mainly two key features of stem cells, one of them is that they can divide by Mitosis, and the other key feature is that they are able to differentiate or turn into specialised cells, one can split and turn into a skin cell, or a blood cell.  

When a Sperm cell fertilises an egg cell. It forms a Zygote, then it undergoes mitosis and forms an Embryo, these are embryonic stem cells.
These cells are embryonic so they can differentiate into any kind of cell, nerve cell, skin cell, brain cell, and in time differentiate into different kinds of cells, then after 9 months, we have an infant baby.

Now let's move to an adult, their stem cells are very different from embryonic stem cells because they can only differentiate into a more narrow range of cells. 
These cells are more specialised, like bone marrow which is inside of our bones and contains adult stem cells, but since they are more specialised, they can only turn into cells. Red blood cells, Platelets and White blood cells, these cells can keep us alive, but they don't form any new tissues. 

Now plant stem cells are a little different known as Meristems found on roots and tips of shoots, as these stem cells are found where the plant is still growing, these stem cells are still persistent and are still used throughout the plant's life, unlike our stem cells when we reach adulthood.

If we can change these damaged or faulty cells, with new cells we can treat these ailments. 
In order to get these stem cells, scientists first gather embryonic cells, then grow them in a laboratory, then stimulate them into the type they want, and then give them to the patient who needs the stem cells. 

Power & Work Done

First of all, Power is the rate of energy being transferred, the equation for this is P=E/T or (Power = Energy / Time).

Work donee works at what rate "Work" is done, so if you push a car down a ramp it is considered to be work done, the equation for this is P=W/T or (Power = Work Done / Time). 

But both these follow the same measurements, power is in watts, energy in joules, and time in seconds. 

So let's use both equations to figure out which lamp is better.
Lamp 1 transfers 1200 joules over 20 seconds.
Lamp 2 transfers 1500 joules over 30 seconds.

For this equation, we will use the first equation, or the P=E/T. Now, we plug in lamp 1's numbers, so 1200J / 20s = 60 watts.
For the 2nd lamp, we put 1500J / 30s = 50 watts.
So even though the second one has more power in the form of joules, because of its time in seconds, the amount of power (watts) is worse than the 1st. 

Let's figure out how much power an 1100-watt microwave need, so first let's turn it on for 3 minutes. First lets change out 3 minutes into 180 seconds by multiplying the 3 * 60(minutes), now we can do 1100 * 180 =  198,000 joules. But when we get a big number we can convert it to kilojoules or 198,000 / 1000 = 198KJ.
  

Reducing Unwanted Energy Transfers

To reduce unwanted energy transfers the most common types are insulation and lubrication. 

For example, when you want to keep a drink cold in a cooler box with ice, you are insulating the box to keep it cold.
This is the same as closing all the windows in your house to trap heat or cold air so that it doesn't escape through convection. Then we have to reduce the heat loss from solids which is conduction, to combat the loss of heat houses are built with thick walls to keep the heat trapped. But certain walls have gaps between the outer and inner walls, which is a space that can also lose heat, so we put an insulator (usually foam) between the outer and inner walls of the house to trap the heat in.
Windows are also important to help reduce the amount of heat or energy lost, and the amount of glazing on the window pane.

Now about lubrication, which is used in all kinds of machinery, typically oils or greases, from wheels to ball bearings, to doors moving, if it moves normally it's pretty oily to the touch and was lubed to make it move smoother.
This also helps with reducing heat conduction which

Mitosis

Cells in every living being need a new supply of new cells, as when you are growing, repairing or undergoing development you need new cells to replace the old cells, like our skin cells which will always fall off our bodies and need to replace themselves.

Every cell has a "Cell cycle", along the lines of.
Growth, DNA replication, Mitosis and Division(Cytokineses).

Firstly the cell grows in size, and now it has more Mitochondria and Ribosomes, usually when a cell is not trying to reproduce and duplicate its DNA is now a noodle-like substance, but once it is ready to duplicate the DNA condenses into Chromosomes.
These affect things in humans like eye colour, Eukaryotic cells like animal cells have two copies of chromosomes which are named 'pairs' of chromosomes, one chromosome is from their father while the other is from the mother.

Humans have 23 pairs of chromosomes so in total we have 46 chromosomes, but other species of life have different numbers of chromosomes, this is why animals cannot reproduce with other animals with different numbers of chromosomes like if an elephant and a bird were to have offspring they have different numbers of chromosomes so it would not work.

So when a chromosome wants to divide into more chromosomes, it first duplicates the 46 chromosomes, but the duplicate stays attached, so you get these X-shaped chromosomes, you might hear people talk about these chromosomes that have "arms". The right arm has the same amount of DNA as the left arm. Keep in mind this is all happening inside a human cell.

Once the cell is ready to divide, the chromosomes start to move to the centre of the cell, and after fibres or microtubules start slowly pulling the arms of both sides of the chromosomes splitting them in half and pulling them to each side of the cell. Pulling it to the 'poles' of the cell, and this breaks the cells apart, this happens to all 46 chromosomes inside the cell.

After all of that, we are finally able to do Cytokeneis or division, the cell membrane and cytoplasm pull apart making two daughter cells.
With the same DNA and the 46 chromosomes split between them, so each cell has 23 chromosomes, and then they repair, and undergo the same cycle infinitely repeating and duplicating. 

Distillation

Distillation is necessary when separating liquids from solutions, which are liquids with a solute inside, like sea water mixed with salt.

For Simple Distillation, first, we must get 2 beakers, one with an offshoot and one without, and connect a glass pipe to it with a water sleeve. 

Stab a thermometer through a bung or cork atop the beaker, and seal the beaker, on the offshoot we put a pipe which is known as the condenser.
And then we put a cold water sleeve surrounding the condenser, and we put a Bunsen burner below the beaker.

Once the water starts to heat up it starts going into the condenser pipe and starts getting cold by the cold water sleeve and condenses on the walls of the condenser turning into liquid and going off into the offshoot and going into a separate beaker that the condenser is pouring into.

But some liquids like: Methanol, Ethanol, and Propanol have similar boiling points, when we heat them up more than one will be separated, so it is very hard to separate them into pure substances. 

For these elements, we need to use Fractional Distillation, which is similar to simple distillation. However, we use a glass filter in the beaker, so when the liquid boils, it filters through the glass.
So let's go back to methanol with a boiling point of 65°c, ethanol at 78°c, and propanol at 97°c.  
So if we start heating up, we will get to 65°c, and then the methanol will start to heat up, boil, and rise up the fractal collum filled with glass rods. It would then go into the condenser and water sleeve and condense into liquid methanol, which would be collected in the beaker at the end of the condenser.

But maybe some of the ethanol and propanol might also follow the vapour of the methanol but since they would get in contact with the cool glass rods, they would condense back into their liquid forms.
Now for the ethanol, firstly lets change the beaker for a fresh and empty one. And now we heat up the solution up to 78°c and once again a bit of the propanol might follow but once it hits the glass it goes back to being liquid. 
Lastly, for the propanol, you must turn the heat up to 97°c, and then the propanol goes into the water sleeve and condenses

Netherlands

Don't call this place Holland as that is just one part of the country.

The country is along the North Sea bordered by Germany and Belgium in the south, the country is split between 12 provinces and their names are as follows:

Limburg, North Holland, Utrecht, Gelderland, Overijssel, Drenthe, Gronigen, Friesland, North Brabent, and Flevoland.

They have two capitals, Amsterdam their largest and economic hub of the city home of the Royal Palace, and the 3rd largest city the Hague acts as the second capital, which holds the sea of government and the international court of justice. 
The second busiest city is Rotterdam which holds the title as the busiest sea port in Europe.  

Their busiest airport is Amsterdam Schipol International, Europe's 3rd busiest airport carrying about a 70million passengers annually. 

Apart from the main country they also hold islands in the Caribbean, from the colonisation, known as the Dutch Caribbean,
the Netherlands is a country that is technically made up of 4 countries. They are Aruba, Curacao and Saint Maarten, which is shared with the French island Saint Martin, so from a technical standpoint the Netherlands borders France. And they have their own constitutions and currencies.

The remaining 3 are Bonaire, St.Eustatius, and Saba, these three are municipalities and do not belong to any province, they did adopt the US dollar as their currency. 
This island lay in the region known as the Lesser Antilles.
Aruba, Curacao and Bonaire are known as the ABC islands lying in the
sub-region Leeward Antilles.
While Saint Maarten, St.Eustatius and Saba islands are known as the SSS islands in the sub-region known as the Leeward islands.
At one point all 6 of these Islands were named the Netherlands Antilles, with their capital in Willemstad in Curacao and even competed in the Olympics.

In the 2000s the Netherlands gave the islands multiple choices, they could either have closer ties with the Netherlands, remain in the Antilles as they are, have autonomy in the constituent country within the kingdom of the Netherlands, or just be completely independent of the Netherlands.
Aruba, Curacao and Saint Maarten voted for autonomy.
St.Eustatius, Bonaire and Saba wanted closer ties with the Netherlands and special municipality status.

Waterways are important here in the Netherlands as water is used as a form of transport, there is even a city named Giethoorn with no roads and only canals.
Around the 9th century, people made Dijks which act as walls from the sea, because they were tired of the land being flooded, the Netherlands claimed around 20% of their landmass from the sea or 1/5th of their country.
If all the Djikes exploded and broke, the whole country would flood and drown.

Notable places to go here are The Teylers, Stedjik, Hague and Maritime Museums, and the most famous ones the Rijks Museum in Amsterdam, the Royal Palace, the Van Goth Museum, and the Anne Frank House.
Castles like: Muiderslot, Paleis het loo, Kasttle de Har, Valkenburg, Palesis Het Loo, Heeswijk.
Many star-shaped towns, and amusement parks like Slagheren, De Efteling, Drievilet and Hellendoorn just to name a few, the Baarle Nassau exclaves and enclaves with Belgium, the biggest flower garden in the world Keukenhof, Austerlitz Pyramid, Hunebedden an ancient burial site, over 1000 historical windmills in the Kinderkijk area which is a UNESCO heritage site.  

The Greek philosopher Pytheas said in ~300 BC "More people have died here against the struggle against water than man". 

The Netherlands is the lowest country in the world elevation-wise, around 1/4th of the land, 1/5 of the population lives below sea level, and 1/2 of the land is above sea level. The lowest part of the Netherlands is Zuidplaspolder, and the highest part of the European part of the country is Vaalserberg over 1000 feet high or 322 meters high.
But the highest part of the Kingdom of the Netherlands is Mount Scenery which is a potentially active volcano on Saba in the Caribbean.

The Rhine River in Europe ends in Rotterdam, the largest manmade lake or bay is Ijssemeer which is contained in the N-22 and N-302 highways. In order to prevent flooding, the Dutch had to make the Delta Works which are large levees which close off sea estuaries, acting as a sort of blockade to stop their whole country from being submerged. 

In the north, the Valden Islands act as a sort of Natural barrier against the sea, with the land reclamation from the sea giving the Netherlands one of the largest open sand drifts in all of Europe.

The Netherlands is still a very strong nation, ranked in the top 20 usually at 16-17th place in world economies, and 5-10th largest exporters in the world.
They have the oldest stock exchange in the world dating back to 1602.

Although they sell 80% of the world's tulip exports and half of the world's flowers, their main source of income is energy and service. Shell is one of the companies that started in the Netherlands, along with Phillips which made the first tape recorder.

Wildlife is very important here as the Dutch make pathways over highways for animals to cross, over 70 mammals live here, hares, hedgehogs, stoats, and deers. 

According to the government website, they produce more than 65 billion Euros from vegetables, fruit, flour, meats and dairy products.
They also bred the first orange carrots, it was meant to honour the king.

Foods to try here are Stamppot, Dutch Poffertjes, Appletaart, Bitterballen, Splitpea soup, Rootworst, Stroop waffle, lots of dishes involving potatoes, Brimed herring and smoked Eel, Gin was invented by the Dutch too, Chocolate sprinkles on toast or Hagelslag, and Gouda cheese (pronounced Hau-da).
Also, they used to produce the most beer in the world until Mexico beat them, along with Indonesian, Malay and Suranamese dishes like Satay.

With a population of over 18 million people, it is the most densely populated country in Europe. With around 77% being Dutch, 10% Europeans, and 13% being Turkish, Indonesian, Molucca, Sudanese and Americans. 

Euro as their currency, with types C and F plug outlets and they drive on the right side of the road.

Dutch is the national language, but most if not all speak English, being ranked very high in the amount of proficient English speakers, with around 9/10 people being able to speak English comfortably around 94% are Bilingual.  
But there are two more languages spoken here Frisian which is spoken in the Friesland region and Papiamento, which is a Dutch creole spoken on the ABC islands. 

The Dutch are one of the tallest peoples in the world, the first in Europe and tied with South Sudan in Africa. Men averaging at 6"1" and women around 5"7". 

Mostly due to natural selection, as most people correlate that being taller helped with being more athletic, successful and healthy, so practically all of the short people were eradicated due to natural selection.

Historically the Dutch were Christian Protestant, around 50% or half of the population is unaffiliated one side being Agnostics or Iatists which are people who are more spiritual than religious, and around 5% being Muslim.
Although Christianity is not the whole country's religion it does have a massive cultural effect on the population. Christmas and Easter are widely celebrated by them in their own ways.

They were once a large empire practically on every continent, at one point Australia was named New Holland and New Zealand after the Zeeland province in the Netherlands, and New York was once named New Amsterdam.

Strangely a Dutch is saying "Doe Normaal", translating to "Act Normal". 

The Dutch are among the few remaining Monarchs on earth, but are considered a "Unitary parliamentary constitutional monarchy." 
Although this does suppress most of the power from the monarchy, the king is still widely considered to be a 'friend of the people' and they also have a holiday named after him and the whole country wears the national colour of orange.

The Dutch also have 'controversial laws' they allow, such as same-sex marriage, legal prostitution, euthanasia, and tolerance to recreational drugs, anything around 5 grams max above is a misdemeanour, you must be 18+ to use it though.

They are world-famous for Field Hockey, Speedskating and Volleyball, they also go sailing a lot, and do this thing called "Sail Amsterdam" every 5 years.

Strangely 1/3rd of the population is born at home instead of in a hospital. 

Clogs which are wooden shoes, were used by artisans, fishermen and other working-class people because they had to protect their feet from fishooks or sharp objects. 
Since newer shoes are much better and boots are more common, very few people still wear them but mostly sold as souvenirs. 

The symbol of the Netherlands is the windmills scattered around the country with about 1200, and was mainly used for pumping out excess water for farmland.

The music here is very Dutch since they contributed to the Baroque period or around the 1600s after the Renaissance, with composers like Jan Pieterzoon Sweelinck organ players like Jacob Van Eyke and vocalists like Unico Wilhelm Van Wassenaer.

Clogs are also used in folk dance for percussion, strangely most Dutch enjoy EDM music 

  

Ancient Egypt and the Nile river

The most crucial part of Ancient Egypt and current Egypt is the Nile River, and the water flows northward through lower Egypt, a river delta is where a river opens into a sea.
The Nile River flows into the Mediterranean Sea, and because it looks like it branches into a sorta triangle similar to the Greek letter Delta or Δ but flipped upside down. 

The Nile flows from upper to lower Egypt, keep in mind when it is lower means north, while upper means south. 
This makes the southern parts of the river in Upper Egypt upriver known as the Upper Nile. 

The Nile River was a trivial part of the advancement and development of agriculture the Ancient Egyptians had a callander based on what the river was doing at that time.
So they had seasons about when the river would flood and cause the surrounding area to be fertile for crops a growth season for when the crops have time to grow, and a harvest season to harvest before the flooding would happen again.

Around 3,100 to 3,150 BCE is when we believe that Upper and Lower Egypt was united by King Menes or Narmer, the empire that he helped unify withstood for over a thousand years.

The Kingdom is split into 3 kingdoms, the Old Kingdom which is from the 27th century BCE until 22nd BCE. 

The thing most people associate with Egypt is the Pyramids and kings known as Pharaohs, the Pyramids of Giza were built during the time of Sneferu and Khufu around the 26th century BCE, we are still trying to understand on how the pyramids were built, we found out that the pyramids were not built with slave labour but instead with well-trained craftsmen and carvers.
And each pyramid may have taken 10,000-100,000 people spanning decades to build each one.

How we know how much about Ancient Egypt was their writing system, being Hieroglyphics, and we learned how to decypher them, and learned that nobility had better gravesites than most commoners. We knew that the pyramids were tombs of kings because of how elaborate they were, but we did not know so much about ancient Egypt until 1799 when we found the Rosetta stone.

The reason why this was important in our understanding of ancient Egypt is that it was written in hieroglyphics, but also the same script was used in ancient Greek and in an Egyptian language named Demonic Egyptian. So using this knowledge we were able to decipher these texts.

Now we must travel through thousands of years of Egyptian history through the Old and Middle kingdoms, and then you have the Hyksos, which are Semitic people and speak something similar to Arabic, and Hebrew.
Then the New Kingdom which is is really like their peak of civilization and the height of technology.

One of the few Pharaohs that are known in the new kingdom is Akhenaten, who changed his name to Amenhotep after the Egyptian god Amen meaning 'satisfied', and Amenhotep disliked worshipping multiple gods. So he started worshipping a single god Aten, since he changed his name to Akhenaten.

And he started getting rid of evidence that the other Egyptian gods existed, this is notable because this is one example of Monotheism, which is worshipping a single god. He is also known to give lots of power to his wife Nefertiti, who practically Co-Ruled Egypt, and their son probably the most well known Egyptian ruler King Tutankhamun, he is also a child Pharoh, he was a kid when we came to power and died at 18.

Another famous pharoh after Tutankhanmum is Ramses the Second, rules for most of the 13th century BCE, representing the peak of Egyptan military might, known for his battle at Keddish, around 1274 BCE, Ramses wasn't able to cappture Kaddish, it is speculated that it was the largest chariot battle in history.

Then the new kingdom perishes and we get to the end of the second melliunum. Then things get a little confusing, the Kushites rule the Upper Nile for a brief period, the Assyrians they also rule for a time, then the Persian's take over, Cambyses, Cyrus the Great's son and conqours Egypt for a while and becomes part of the Achaemenid empire for a while.
Alexander the Great shows up, and then after he dies one of his generals takes over and it becoems Ptolemeic Egypt. Then Cleopatra takes over and is consdierd to be a "Pharoh", then after her death it becomes part of Rome. 

How to convert between nm, um, mm, m and km

 The: nm, um, mm, m and km.

Are all units of measurement, depicting size. Nm for nanometers, um for micrometre, mm for millimetres, m for meters, and km for kilometre. 

Now each of these numbers is either 1000 times bigger or smaller than the previous one.
To convert each number, simply divide or multiply it by 1000, so if you want to convert 2 kilometres into meters, all you have to do is multiply 2 * 1000, and you get 2000 meters. Then if you want to convert it back to km do 2000 meters and do
2000/ 1000, and then you will get 2 kilometres.

Now let's take an example number of 6mm or 6 millimetres.
In order to increase the 6mm in size, you have to divide it by 1000, so if you want to convert the 6mm to meters then it would be 0.006 meters or 6x10^-3 meters, it is still the same number of 6mm but since the unit are larger the number is smaller. 

Now if you want to convert the 6mm to um or micrometers, you would multiply by 1000.
So, 6mm * 1000 = 6000. Or 6000um or micrometres, or 6x10^-3um. 

Now let's put these all into scale, atoms are 0.1 - 0.5 nanometers big, viruses are around 100 nanometers across, bacteria might be a micrometre, and plant and animal cells are around 10-100 micrometre range.
But not even the best eyesight can see past nanometers in size, as the smallest thing we can see is the width of the human hair, light microscopes allow you to see around 500 nanometers, but if you have a selection microscope you can see until 0.1 nanometers which is the size of atoms.

Filtration, Evaporation & Crystallization

We can separate soluble and insoluble solids from liquids, by using Filters, Evaporation and Crystallization.

First, an insoluble solid is something like sand in water, since it doesn't dissolve is it is a mixture while if we have a liquid and put something soluble like sugar it will dissolve and it is called a solution the sugar being the solute and the water being solvent. 

Filters are usually used in cooking by using a sifter, but in chemistry, we use something called filter paper, which is paper with very small holes in it.
The holes in filter paper are so small that only water can pass through and most solids can't, even individual grains of salt or sugar to sand can't pass through.
Normally we cover a funnel with filter paper so we can easily pour water into the funnel and the filter paper filters it for us. 

A Solution is when there's a soluble solid, that mixes into a liquid, like salt, but if we want to separate the liquid and solid we have to use Evaporation because we can't use filter paper since the salt is already mixed with the water.

So if we want to extract sea salt, first we must put the seawater into a suspended dish, and then we heat up the liquid inside with fire or a bunsen burner, after a while you will notice that the water evaporates and what is left are crystals, in this case salt crystals.
One thing that's good about using evaporation is that it is a relatively fast way to remove the liquid from the solid.

Some solids will decompose when heated up, the heat causing the solid that we want from the evaporation process to be broken down into something that we don't really want.

For solids that we want to separate from liquids, but don't want to be broken down and decompose, we have to use a slower method named Crystallization, once again we must take the liquid and heat it up in a dish, but time we must make sure to heat it up more gently instead of quickly.
Instead of letting the crystals form and continuing to let the liquid heat up and decompose the solid that we want. We stop heating it after crystals form, and let it aside to cool, an more crystals will form because solids are less soluble at colder temperatures. 
Finally, we can use a funnel covered by filter paper and pour the liquid with crystal in it, filtering it and giving us the solid we need from the liquid. 

Conduction, Convection & Radiation

There are multiple ways heat can be transferred between objects. 

Conduction happens through solids, Convection through liquids, and Radiation through the air.

Let's start off with Conduction, first, we take a metal bar, since it is solid, the particles are very highly knit so it is very easy for it to transfer heat, so when we heat up the metal bar with a Bunsen burner, the particles start getting charged with kinetic energy causing them to move a lot and since they are so tightly knit the heat is transferred throughout the solid.

If you heat certain materials, you might notice that they can be heated to different temperatures. That is called "Thermal Conductivity." For example, metals have much higher thermal conductivity than plastic, which has very low thermal conductivity. 

Convection occurs when you heat up any liquid or gases.
The heat charges the particles with kinetic energy, causing them to move from the warmer regions to the colder regions.
When it is colder, the particles are less spread out than in the warmer regions.

That is why when you heat things up, they expand slightly, and when liquids or gases heat up, they become less dense because the particles are no longer near each other. 

This is why we wear blankets when we sleep in cold environments which keeps the warm air from our bodies from escaping the covers. 
And why do we have to close the windows and doors to keep the cold air from an air-cond from flowing out of our homes, or aircon's, oceans and heaters use a Convection Current to keep the fluids or air circulating.

The thing that convection and conduction have in common is that both have particles gaining kinetic energy, but what separates these is that only the energy is transferred while convection is that the particles move. 

Radiations are when energy is transferred via air or a vacuum, a good example of this is the sun's rays, which are transferred by solar radiation going through space which is a vacuum into our atmosphere, same with a microwave. 
Radiation travels using infrared waves, all objects absorb and emit radiation, how hot an object is and how much radiation it emits. Hence the sun and its heat, and why you cook food around it is hot.

Light & Electron Microscopes

 There is a difference between Light and Electron microscopes, most microscopes we use are light microscopes which are lighter in weight cheaper to purchase and easier to use than electronic ones. But that comes with some drawbacks, as we can only see stuff that is 0.2 micrometres so our resolution can only go to 0.2 micrometres because light has a wavelength of 0.2 micrometres and we use the light to focus on the subject, 
and if we try to zoom in further than 0.2 micrometres it will be unfocused and blurry.

While electron microscopes are heavy, expensive and hard to use, and only really used by scientists, election microscopes use electrons instead of light which enables you to zoom in until 0.1 nanometers, electron microscopes have a nearly 2000x zoom compared to light microscopes.
They are normally used to look at sub-cellular structures, so you can look at the nucleus of cells along with the mitochondria, but they also have no colour and thus are black and white since that there is no light going into the subject. 

Conservation of Energy

The first law of Thermodynamics is that energy can be transferred, stored and dissipated but cannot be created nor destroyed.

For example, when you plug your phone into a socket to charge it, electrical energy is turned into chemical energy in your phone's battery. And using the chemical energy that was being charged by the electrical energy from the socket to power things such as the screen which turns the chemical energy into light energy, or play sounds by converting it into sound energy. 

But you can never have 100% energy transfer, it's because there will always be wasted energy.
Most wasted energy is lost due to the energy generating heat, like when you are charging something your phone gets warmer, or a car tyre is spinning rapidly causing friction which causes the tyre to get warmer.  

There are types of systems: closed and open systems. First, we have to select one. Let's say we take your phone as a system. The system would be the phone, while the outside world would be named the "environment." In this case, the phone would be an open system because it can be affected by the environment or outside factors. Because this is an open system, energy can flow between the environment and the system.

While a closed system stops all outside factors or the environment entirely.
If you put your phone in a sealed jar. Everything inside the jar is the system, and because it is in a sealed jar it is not affected by outside forces or environment factors.
So when the phone heats up, the heat is trapped inside the jar and it stays within the system.

Balancing Chemical Equations

Chemical equations are very important for written Chemistry, for example, if we take Methane + Oxygen -> Carbon Dioxide + Water, the underlined words are products, while the non-underlined are not.

Now to write this as chemical symbols you would write it as:
c
the Ch4 is because there is 1 carbon and 4 hydrogen. For the O2 it is because O2 is 2 oxygens.
While the products CO2 + H2O, has the CO2 has 1 carbon and 2 oxygen, while H2O has 2 hydrogen and 1 oxygen. 

Now if you want to "balance" these equations, it is mainly done by trial and error, it is because you can't change the subscripts because it changes the whole element to a completely different one.
But we can change how many of the elements there can be, to balance the
Ch4 + O2  -> CO2 + H2O.

So if we look at the products, we might notice that there are 3 oxygen molecules compared to the 2 oxygen molecules on the reactants side. 
So to make the equation "balanced", we must match the number of oxygen atoms on both sides. So we give the O2 on the reactants a 2O2 instead so that both sides have 3 oxygen molecules. 

But you almost might notice that we did not give
1 1/2 molecules of oxygen, to "balance" the equation, that's because we can't give half an oxygen molecule we must stick to whole numbers when balancing.
Now what about the other side of the products, well we also need 1 more hydrogen and 2 more oxygen on the right so we add 2H2O, and these are now balanced.

  

Microscopes

Light microscopes are highly important in Biology because they allow you to see the smallest things like cells.

First lets start with the base, which connects to the arm, then there's the "Stage" which is where we put our objects on to examine them. 
Usually there's 3 objective lenses, with different magnification strengths, then there's the lens at the top which is where our eye goes and has a fixed magnification, then the tube which goes from the lens at the top to the lenses at the objective lenses,
then the coarse and fine focusing nobs to focus the lenses on the object on stage.  

Let's get this straight, there are two things that are important when looking through the magnifying glass (there's more but that doesn't matter right now), mainly the "image" and the "object".
When referring to the object you are usually referring to the object or sample you are looking at on the stage. So if we have let's say onion cells on the stage, that would be considered to be the "object" or "sample". 

The term "Image" comes from the image that we see when we look down, we see the individual cells, and what we see in the lens is the image. 

Light Microscopes work by shining or reflecting light onto the subject.
Or by using an adjustable mirror below the stage or by turning on a lamp at the bottom to illuminate the clear stage. 

First, the light shoots up towards and through the sample, then through the objective lenses, then through the tube then into the lens where our eyes are.
This, in turn, is necessary for the light to bounce off objects for our eyes to see, magnification happens when you magnify the object, so an x100 magnification means the object is magnified 100 times. 

Resolution means how detailed the image is, so if an object has a terrible resolution it is very blurry, while a good resolution is good when it is crystal clear and very sharp. 

Differences Between Compounds, Molecules & Mixtures

 Mainly elements fall into 3 categories, Molecules, Mixtures and Compounds.

Molecules refer to elements bonded via chemical bonds, a good example of this is Oxygen, which is bonded together so they are classified as a molecule, but these molecules can also be made of multiple different elements, such as water which is H20, others being Hydrogen, Chlorine and Carbon-dioxide. Molecules need 2 or more elements in order to be considered a molecule.

A Compound is made out of two elements held together by chemical bonds, for example, water is also considered a compound because it contains hydrogen and oxygen.
Along with carbon dioxide because it is made out of oxygen and hydrogen. But water, chlorine and hydrogen are not considered compounds because they only have one unique element.
Another thing about compounds is that they are found in the same proportions, so you wouldn't see a water compound with one more hydrogen. Water will always have two hydrogen atoms and one oxygen atom. And it is consistent and never changing.
Since it is consistent water will always be H2O. Now the smaller 2 is written in a "subscript" which signifies that the H in the water molecule is that there are two hydrogen atoms, and carbon dioxide is always going to be CO2, the 2 being that there are two oxygen atoms. 

Another element is H2SO4, which always has 2 Hydrogen (H2), one Sulfur (S), and four Oxygen (O4).
But for some elements, Calcium for example: Ca(OH)2, the calcium is made out of one Calcium atom (Ca), and two of OH or (OH)2. 
These atoms are actually very small as some atoms contain up to a billion atoms, like table salt or Sodium Chloride which has the elements NaCl.  
But unlike other atoms, sodium chloride has as large structure compared to other atoms, sodium chloride has an Ionic bond, and the NaCl or table salt is a 1:1 ratio, so that if there's a Na atom there is always a Cl atom.

Mixtures are substances that are not bonded together. So if we combine sodium chloride, oxygen, individual helium atoms, and carbon dioxide this would be considered a mixture, 

Internal Energy and Heat Capacity

Internal energy usually comes into two forms: Potential Energy stores, and Kinetic Energy stores.
Most potential energy stores come from Gravitational and Elastic energy, this isn't really related to temp but is good to know. Kinetic energy on the other hand is very important as the movement is an energy store.

When you heat up anything, you are converting the heat into kinetic energy stored which we can measure in an increase in temp, which is a measure of the "Internal temperature" of a substance.  

However, substances need more energy to increase their temperature than other elements, as water needs 4200J or 4200 joules of heat in order to warm 1kg of it by 1°c. 
Compared to Mercury which only needs 139J of energy to have 1kg of it to be 1°c  hotter. These numbers are called "Heat Capacity."
The inverse is also true, so when water cools by 1°c, the water is relicensing 4200J of energy while cooling. 

Gravity and Weight

The Earth's core is the reason why Gravity exists, gravity is a force that attracts objects together and relies on mass as well as the distance between the two objects,
that is why when you travel in the ozone layer gravity is weaker. 

Everything has a gravitational force pulling things towards it, like an apple and a skyscraper, there is a gravitational pulling the apple and skyscraper together but it is so slight that it is practically non-existent. 

For large objects, or in this case.
Planets, have a much stronger gravitational pull than an apple, having a file of influence around it. We, humans, have dubbed this a "Gravitational field" and the strength is the "Gravitational field strength" In, in Physics we show the letter "g" as gravity, which if we are talking about Earth is around 9.8 newtons per kilo, but if you take the moon it would be 1.6 newtons per kilo because the moon is smaller and thus has a smaller mass.

So whenever an object comes into a gravitational field it is attracted or pulled towards the gravitational field, so to calculate an object's weight, we take its mass and multiply it by the gravitational field strength (9.8) so if someone weights 60kg, we multiply 60 * 9.8 giving us 588 newtons or 588N. For this, we would say we have a weight of 60kg, not a mass of 60kg.
Mass refers to the basic characteristic of the object's mass, and Weight is how much the force of gravity affects it.

When you jump you are expending energy and putting it in the "Gravitational potential energy store", the formula for gravitational potential energy store is 
Ep = mgh or Mass * Gravitational field strength * height the measurements are mass (kilos), gravitational field strength (newtons per kilo) and H (Height), and Ep is measured in Joules.

Now let's take an apple with a mass of 100 grams and we throw it 3 meters into the air.
First, we have to convert the mass to kilograms to make the equation easier, so we convert the 100g to 0.1kg by dividing the 100g by 1000 (because one kilo is 1000 grams). Then we multiply the 0.1 (weight) * 9.8 (the gravitational field strength) * 3 meters (height), and we get 2.94 joules of energy.

Once again gravity relies on the mass of an object and how far it is from other objects, so planets will attract space debris, but rocks cannot attract other rocks on earth, because of the mass difference between a planet and a rock.

Nepal

Nepal and India have a large dispute on where Buddha (the person), was born because Nepal says Lumbini which is in Nepal but India says that Buddha grew up in Kapilavatsu for the first 29 years of his life which they argue is in Piprahwa which is half a mile or 800+ from the Nepali border, then the Nepali people argue that Kapliavatsu is in modern-day Tilaurakot. Then the Indian's argue that it was during the Mahajanapada area when Nepal wasn't even established as a country.

The most common things people know about Nepal are: Sherpas and Mount Everest the tallest mountain in the world claiming hundreds of lives to those who climb it.

Geographically they are sandwiched between China and India and contained to the Himalayan mountain range, the country is split into 7 provinces but strangely only 3 have names those being: Province 1, Madhesh Pradesh, Bagmati Province, Gandaki, Lumbini, Karnali and Sudurpaschim.
Originally the country was split into 14 zones that are still used for license plates.

The capital Kathmandu located in Province 3 or the Bagmati province, the largest and busiest airport is Kathmandu's Tribhuvan International, but due to tourism, they have made 3 other airports those being: Nji-Gadn, Pokhara and Gautama Buddha Airport.

Oh, and they also have the most dangerous runway in the world which is Lukla airport which drives off a cliffside, so if you don't build enough speed to fly you plummet downwards.

Also, they act sorta like a buffer between the two giants India and China, this comes with its pros and cons, and one of the pros is that they are basically surrounded by two large countries. And since they are basically surrounded by these two countries Nepal is one of the very few countries to never be colonised, they were definitely influenced and invaded, but never fully colonised by external peoples.
Since they were never colonised the land transport is unique, they have roads heading into both China and India, but to go into Kathmandu you have to go to the heart of the mountain so you only have a few highways to get there like the H02 highway from India and the H03 which goes into Zhangmu-Zhen in Tibet China.

There is a disputed territory in Nepal which is the Kalapani territory, it was a byproduct of the 1962 border war between India and China.

Interesting places to visit are The Annapurna National History Museum, Narayanhiti Palace, Pokhara (basically the tourism capital), Chitwan, Tiger tops and Elephant Polo fields, the Toothache Tree, the Aviation Museum, religious sites like Pashupatinath, Manakamanab, Budanikanth, Muktinath, Rincheling Gompa, The Ronbuk Monastery, Lumbini (the arguable birthplace of Buddha, and the Boudanath Stupa. 

Nepal is located at the start of the Himalayan Mountain range, the tallest mountain range in the world it was caused by the Indian tectonic plates colliding with the Eurasian plate and the collisions are still happening meaning that the Himalayas are getting taller by 6.1 or 2.4 inches a year. 

The tallest mountain in Nepal is...Mount Everest is nearly 9000 meters high or 9km tall and has 8 of the tallest mountains in the world just in the mountain range itself. Since the technotic plates are active the country is subjected to Earthquakes the strongest being a 7.8 magnitude earthquake in 2015, along with that it triggered an avalanche on Mount Everest killing 21 people. 

The country has 3 regions, the Himalayan mountain range, the Pahad which is below the mountains which doesn't get snow and has fertile land and rivers, lastly the Terei the lowest part of Nepal located in the greater Gangetic plain that extends to northern Bangladesh and India.
The lowest point is Kechana Kalan 70m above sea level, China this makes Nepal one of the countries with a large amount of elevation changes, the Kechana Kalan area is the most fertile which is where most of the agriculture is grown. 

The largest river is the Ghaghara which is found in the west and the largest lake is the Rara, but still, the Baghmati River runs through Kathmandu and the Gandak River has the largest Hydroelectric dam, while the Koshi River supplies most of the water to the lower parts of Nepal in the east.

Nepal does struggle with their living index of animals they are still a heavily agrarian society with nearly 65% of the population in agriculture, and half of the development funds come from foreign aid from other countries. Their exports largely are textiles, clothing and carpets. 

They are trying to use the tourism sector of visitors to their advantage normally through tours and guides through the mountains with obviously Mount Everest. Being the most expensive.

When you want to go up Mount Everest you have multiple choices for agencies for travelling up. The Western ones will be pretty pricy up to 45,000+ USD per person, the Nepali agencies being cheaper but a language barrier might exist, but the 25,000+ is much cheaper than the Western agencies. You can also just hire a helicopter to fly up but only one person has ever done that being Didier Delsale from France but it is incredibly dangerous.  

Around 40% is forested with 9 national parks and 3 wildlife reserves. 
The national animal is the cow with the Hindu population of Nepal regards them as sacred animals, many are vegetarian or eat chicken or fish. 

Some popular foods here are Dhindo, Gundruk, Daal Bhat Tarkari, Thakali Khana set, Choila, Kachila, Chatamari, Nepali pani puri, Nepali Aloo Chana, Laphing, and Momo dumplings. 

Nepal has over 120 Ethno-linguistic groups, with a population of around 30 million people with over 2 million working abroad usually in the Middle East. With the Chhettri being around 17%, Brahman-hill at 12%, Magar at 7, and the Tharu at 7% also, the rest 57% is made out of other groups.

They use the Nepali rupee, which is pegged to the Indian rupee, type C, D and M plug outlets and they drive on the left side of the road.

With over 120 people, most speak Nepali which is sorta of a cousin to Hindi which is spoken by roughly 45% of the population. But English is still used in government as a bridge because not everyone speaks Nepali. 

Around 81% of the population is Hindu, even at 10% which is considered a minority Nepal takes Buddhism very seriously.

Most belong to the 7 "Family" groups, the mountainous Bhoti, Sherpa and Thakali at the Himalayan zones, the Gurung people usually serve in the Nepali military under the Gurkhas.
Then the Kirani, Rai and Limbu people in the east, similar to the Bhutanese and Sikkim, with 3/5ths of the population the Pahari people are the most widespread around Nepal, they are very focused on agriculture and having amazing textiles. 
The Tamang are about 40 clans scattered throughout Nepal and are extremely Bhudhist.
Then the Tharu people in the south, are generally immune to malaria due to their Thalassemic blood which is inherited which is a blood disorder.

The "Original" Nepali are probably the Newar people found in pockets around Nepal but mostly in cities. They are considered to be the most advanced in economics, politics and society. 

Many Nepali follow a Tantric tradition that requires 5 animals for a ritual sacrifice: water buffalo, goats, ducks, and chicken, but they must be male.
The Himalayas are considered to be the "Abode of Lord Shiva", and every town has a Jatra which is a celebration of their main god or goddess and a statue of their god/goddess is paraded around the town. Along with a 15-day celebration of Dashain.
As well as the Kumari which are young girls treated like goddesses until they reach puberty. 

The short history is: The Kathmandu neolithic age, Nepal being spoken about in the Vedic Hindu texts, the Kirati kings period, the small kingdoms and clans, Siddharta Gautama, vassal states under the Maurya and Gupta empires, Prithvi Narayan Shah put together modern-day Nepal, the Angolo Nepali war, the Treaty of Saguali, the Kot massacre, slavery abloshed in 1924, royal family drama, the 2001 royal massacre, King Gyanendra Bir Bikram Shah Dev steps down as king ending Nepal's title as the last Hindu kingdom in the world, unified communist party, the 2015 earthquake, the first female president, and now today.

Although they are considered a "communist party" which yes they do follow some communist policies, they are not considered a communist country. 
Instead, it is a parliamentary republic which is a parliament which has control over the head of state. Nepal is the only country that has a communist majority vote but is not wholeheartedly communist.

Famous people from Nepal are Amshuverma (ruler), Princess Bhrikuti, Sankhadhar Sakhwa (hero/philanthropist), Araniko (artist), Rana Habadur Shah (king), Bhimsen Thapa (ruler kinda), Laxmi Prasad Devkota, Jhamak Ghimire (writer), Amrita Acharia (actress), Tenzing Norgay (one of the first 2 to scale mount Everest), Gopal Prasad Rimal (poet), Anil Gurug (athlete), Gaurika Singh (athlete), Dachiri Sherpa (athlete), Sandeep Lamichhane(cricket player), Prabal Gurung (fashion), Chandra Bahadur Dangi (the shortest man in the world), David Lama (mountain climber), and Siddhartha Gautama or the Buddha.

Although roughly 10% of their population is Buddhist Myanmar, Thailand and Cambodia are in good relations, usually taking pilgrimage trips to Nepal to visit holy sites usually in Lumbini.   
They kind of have some tension in Bhutan because of the Nepali Lhotshampa residents in the 90s. 
They have good relations with China and India, China is building a railway from Lhasa to Kathmandu, for India most of their trade comes from India, most people in Nepal can understand Hindi and watch Bollywood films, and both countries are Hindu.
They are also good friends with Bangladesh, often using Chitaggong over their own Kolkatta port, and Nepali studies study in Bangladesh and have agreements about trade and transit between countries. And Nepal helping with power by supplying electricity via hydroelectric dams and giving electricity to Bangladesh.

Types of Life

 Animals, Fungi, Plants, Protocysts, Bacteria and Viruses are all different but they are all different types of Life.

Animals, Fungi, Protists and Plants are Eukaryotes, meaning they are made of Eukaryotic cells DNA is stored in chromosomes and their DNA is found in a Nucleus inside the cell. While Bacteria are Prokaryotes which means they don't have a nucleus their DNA is loose floating around in the cell, like a stand of string floating in water.
Viruses on the other hand do not count as organisms so they don't meet the criteria of being either a Eukaryotic or Prokaryotic cell, they are also 10 to 100 times smaller than prokaryotic cells.

There are to our estimates 5-10 million different species of animals on earth, from fish to insects to birds to humans, but the one thing similar to all is they are Multicellular and they are Heterotrophs.
Most reproduce sexually, and each animal is made out of multiple cells instead of one.
It is thought that an adult human is made out of 40,000,000,000,000 cells or 40 trillion cells, so in order to get energy humans and animals need plants or other animals to gain energy.

Plants on the other hand with around 300,000 species on earth, ranging from tomato plants, to trees to leaves. Like animals, plants, are multicellular and they are Autotrophs instead of Heterotrophs meaning that they get energy from the sun via photosynthesis instead of consuming other organisms. 

Fungus are different from plants, they are mostly multicellular, most forms are mushrooms or fungi growing on sandwiches, but yeast which is used in bread is unicellular which means they are made of one cell. Although they look like plants, the key difference is that they cannot photosynthesis instead they get their energy from other sources like animals so they are Heterotrophs, but that's not fully correct as fungi are Saprotrophs which means that they feed using digestive enzymes outside their body to and wait for the enzymes to break down the food and then digest it by absorbing it into their bodies.
Although some of the multicellular ones have a body known as the Mycelium which is made from small string-like substances called Hyphae.
Although rare some fungi are considered Pathogens which means disease-bringing to humans for example Athlete's foot is a fungus that grows on your foot.

Protoctists/Protoctista/Protists/Protista. Are all basically the same thing, nearly all of them are unicellular meaning they are made of singular cells, cells like Chlorella and Euglena are similar to plant cells due to them having chloroplast, while other cells like Amoeba are similar to animal cells because they have to consume other organisms to survive. Most protoctists have nothing to do with humans although some are considerd pathogens and are harmful to humans like Plasmodium which causes Malaria. 

Bacteria live practically everywhere from skin, to the ground to even food, although some species can photosynthesize bacteria in general don't have chloroplasts, but most feed of other organisms maybe dead leaves or living organisms like humans. 
Scientists speculate that there are more species of bacteria than all the other species of life on this planet combined. Some are harmful like Salmonella which causes food poisoning, but most don't bother with humans, in fact some are even helpful to humans like the bacteria in our intestines that help digest food that we eat.

Viruses are basically small tiny particles, for a sense of scale you can fit around 1 million of them along the width of a single fingernail, all viruses are different but all have similar features like a Protein coat around it.

  

Elements, Isotopes and Relative Atomic Mass

The amount of protons tells us how heavy and what number it is assigned to in the periodic table, so Hydrogen is the lightest and has a single proton and electron.

Next on the line is Helium because it has 2 protons and 2 electrons. As you look at any periodic table, there are over 100 different elements some that act similar to each other but they are different. Copper and Tin are different elements, but they are both metals. 

The number at the bottom of most elements is the Atomic symbol, which is unique to every element, as it is the number of protons in the element, and elements cannot overlap in atomic numbers. 

If we take another element...Carbon its atomic number is 6, so every carbon atom should have 6 protons, if we take an atom with 3 protons it cannot be carbon but instead, it is Lithium.
Also the alphabetic letter on the element says its name so Li is Lithium, C for Carbon, but not all elements follow this naming scheme, a good example is Fe or Iron and Na which is Sodium.

Well if the number of protons determines the element, what about Neutrons, well neutrons vary between elements and even in the same element we call these kinds of elements Isotopes. The definition of an isotope is that
"They are different forms of each element that have the same number of protons but not neutrons."

If we take carbon, the most common version of carbon is Carbon 12 which has 6 protons, electrons and neutrons, while another form is Carbon 13, which has the normal 6 protons but has 7 neutrons and 6 electrons.

Something to keep in mind is that all isotopes alike elements have different masses, let's take copper for example.
Copper has two stable isotopes, copper 63 taking around 69.2% of all copper elements, and copper 65 has an abundance of 30.8%, when we are talking about the abundance of an isotope it means how common these isotopes are.
In a quiz or exam, you might see a question like: "Calculate the relative atomic mass to 1 decimal place".
For this equation, you will do "(the sum of all isotope abundance * mass) divided by the sum of abundance of all isotopes".
So lets take copper-63 which is 69.2% * 63 (copper 63), but for copper-65 it would be 30.8% * 65. Then we add both equasions (copper-63 + copper-65) then we add the isotope abundance of 69.2 + 30.8.

So the 69.2 * 63 is equal to 4359.6 and the 30.8 * 65 is equal to 2002, then you add them together to get 6361.69,  then we divide them by the 69.2 + 30.8 which is equal to 100. so we divide 63.6169 / 100. And we get 63.6169.
But the question wants it to be "Calculate the relative atomic mass to 1 decimal place", we will instead put 63.6 instead.