Chemistry pt. 8: Covalent bonds

 Instead of stealing atoms, let's share them.

Let's take an Oxygen atom, it has 6 valence elections. And let's take another Oxygen atom with 6 valence elections. Now these atoms would love to gain or share an electron to make themselves stable. Now sharing these elections causes these Oxygen atoms to stick to each other.
Also known as a Covalent bond, which is a type of bond that is a fusion of two atoms. And it can make atoms more stable. 

Now what about water, how does Hydrogen bond with Oxygen, once again Oxygen has 6 valence electrons. But Hydrogen has 1 valence electron, water requires two Hydrogen and one Oxygen or H2O. 
Now to explain this more easily, the Oxygen atom in this case has 6 valence electrons and the Oxygen atom shares two of its valence electrons, and both of the Hydrogen atoms share their single valence electrons. Now the Hydrogen atoms bond with the two shared valence electrons.

Molecules are 2 or more atoms that are Covalently bonded together, some molecules that are covalently bonded are:
O2 or Molecular Oxygen, H2O or Water, CO2 or Carbon Dioxide, CH4 or Methane, and NH3 or Ammonia.

But there are differences between elements as you well know, for example.
A canister of O2 and a water bottle of H2O is very different.

Diatomic elements are elements that cannot be found in nature and are. Covalently bonded together, like O2, other diatomic elements are: H2, N2, F2, Ci2, I2 and Br2.
These diatomic elements are considered Molecules but not compounds. As compounds are two different elements bonded together.

Certain Covalent bonds are done through a network, one example of a covalently bonded element is Silica or SiO2, which is mainly found in sand, a Silica covalent bond are made with Silicon and Oxygen atoms.
For the formula of Silica, there are two Oxygen and one Silicon atom.

A salt is an atom that is both Ionic and Anionicly bonded together, like Sodium Chloride, or commonly known as table salt, 
as a Na+ ion will attract all Cl- and Cl- ions around it.

As stated above a compound is two different elements bonded together, these can either be bonded ionically or covalently, H20 or water is a covalent compound because it has two different elements bonded together, NaCl is a ionically bonded compound. All salts are compounds, but note that not all substances are compounds. For example, Helium is made of He atoms, and is not a molecule or a compound, and Oxygen gas, O2 is comprised of Oxygen atoms, but not a compound, or a molecule.

 

Chemistry pt. 7: Ionic bonds

 Let's use the group 1 element, let's use sodium. We can use a Lewis dot structure, to visualize this we just draw the element of Na in the middle and draw a single dot on it, the dots on the Lewis dot structure or Lewis diagram mean the number of valence elections.

Let's take two atoms, one Sodium and one Chlorine atom, now Chlorine has 7 valence electrons while Sodium has one, the Chlorine really wants to become a "full atom", meaning 8 valence elections or zero electrons, and the Sodium also wants to be a "full atom" by removing an atom. So what happens if the Sodium gives its valence electron to the Chlorine thus both of them being a full atom.
And since now Chlorine has 8 valence electrons so now it has a negative charge, while Sodium has a positive charge, and what did we learn in physics and in magnetism, well opposites attract.
They form a compound named "Sodium Chloride", or to common folk, table salt. 
A plus one charge for the Sodium and a Negative one for the Chlorine and combined they become a neutral charge. 
This is called an "Ionic bond"

Bonds are when two different atoms either take or give away a valence electron, they become a "bond" thus making a neutral atom combining both to make a "single" whole Ionic bonded atom.

When a neutral atom loses one or more electrons while keeping the amount of protons the same it becomes a cation which is an ion with a positive charge.
And when a neutral atom gains an electron it becomes an anion.

The elements from groups 1,2 and 13 - 18 normally form ions of one charge. So a cation is any element with the word "ion" at the end, so Na ion would be a sodium ion or a Sodium +1 atom.

Certain elements will change their names depending on if they are an anion or cation. For example, for negatively charged ions or anions, a Suflur anion would be a "Sulfide", and a negatively charged Nitrogen would be "Nitride", so what we do is we take the root name and add "ide" at the end.   

And when naming ions or cations, you just say the element and then "ion" at the end. For example Hydrogen ion.

Name the cation first then the anion last, because it comes first in the periodic table. All anions and cations must be written with the lowest integer value. 

Now let's get an example, a Possasium atom (K) is in group 1 of the periodic table so it can have a positive charge or K+1. Chlorine.

Let's take a white cation and a blue anion. One is a positive charge, while the other is a negative charge, and as we know, opposites attract. So they will want to form in ways that will maximise the attractive forces and minimize the repulsive forces. 
Now let's take an element, Rubidium Bromide if we were to separate these elements into their anions and cations. It would be a Rubidium cation and a Bromide anion. A Rubidium element has 37 elections, but since it is a cation and it has lost one of its elections, so now it looks more like Krypton, which has 36 elections.
Now the bromide anion even though it has only 35 protons is going to gain an electron and now has an election amount similar to Krypton. These two elements have the same amount of electronics, but Rubidum has 2 more electrons than Bromide. And now Rubidum will be smaller compared to the Bromide atom. 

Chemistry pt. 7: Valence electrons and ionic compounds

 When we are talking about a group, we are talking about a vertical column. 

Even if a column of elements has different atomic numbers, what matters is its valence elections, meaning they have similar properties, valence electrons are reactive, and elements with similar valence electrons will have similar properties, and when an element has the same amount of valence electrons they are put into a group.
What a "Full outer shell". In chemistry, a full outer shell is when you have 8 electrons, but the only rule here is that the first shell gets full after 2 valence electrons.

Helium, even though it only has 2 elections. It is still a very stable element.

For example, group 18 (vertical column 18), or the "Noble gasses", while the Halogens (group 17) has only 7 valence elections, as they are 1 election away from the noble gasses. These Halogens like to attract electrons, to form a negative ion or an anion, one example is Florine or a -1 Florine anion, -1 Chlorine, or a Chlorine anion, a -1 Iodine. 

If you go to group 16, the Oxygen group, you will find that these elements have 6 valence electrons, so instead of losing 6 elections to become stable, they instead do their best to attract other elections to have 8 valence elections, you might see Oxygen as an Oxide anion (-2 Oxygen), Sulfur as a Sulfuer anion or a -1 Sulfide anion.

The ones on the left most, or group 1 are the Alkali metals, it instead easier to lose one election instead of gaining 7 elections. These Alkali metals want to give away electrons to become stable, so you would often see a Sodium ion with a +1 charge, or a Lithium-ion with a +1 charge. 

Let's go back to Helium, if it wanted to add an electron it would become a Hydrogen atom.

Chemistry pt. 6: Ionization energy trends

Ionization energy is energy to required to remove the highest energy electron from an atom.

If you go down a group, removing the highest energy electron becomes easier, or ionization energy decreases the further you go down.
And if you go from left to right on the periodic table, the energy that is necessary to remove the election increases.

Chemistry pt. 5: The Lewis diagram

The Luwis diagram is similar to the Bohr model as it is a simplified Bohr model, so let's take a Nitrogen atom, it has 5 valence electrons, 7 total elections but 5 valence. So to draw a Lewis diagram for a Nitrogen atom, you would just draw the Valence elections, without the rings,.

Now let's take a Nitride Ion, which is a nitride atom that gained 3 elections, so a nitride atom has 8 valence electrons,
if we were to draw a nitride ion with the 8 valences it would be an N with 8 dots around it,
and those dots being the Valence elections, now since it added 3 elections, it is now a negative 3 charge, and you would write an N with 8 dots around it, but because it is a negatively charged ion, it would have brackets with -3 outside it.

Chemistry pt. 5: The Bohr model

Atoms, it is nearly impossible as you cannot see atoms due to your naked eye, so we use models to visualize these small atoms.

These models can be used to predict and explain the behaviour of atoms.
All models are simplified to a degree, either for simplicity, visibility or usability, if we were to make it more accurate it would be the real thing.

What is a circle with rings around it, those rings are commonly named "shells", they are for the electron atoms which are dots on the shellsand depending on how far the dots are from the centre circle, it means that the electron atom is different.
Something to keep in mind is that the first shells can only support 2 electron dots, and the others can only hold 2 as well.
It uses an N system as the first shell has a value of 1N, while the second has 2N, and then the third has 3N.

1N has 2 Electrons, 2N as 8. Do keep in mind that these are not the actual positions of electrons.

Some elections can only exist on certain energy levels, we use a system named EV or an energy level diagram, the diagram can show us what energy the election is at without needing to draw dots on the Bohr model. 
Let's say our imaginary atom has levels of 0ev, 4ev, 6ev and 7ev.
So in this situation, the election can only exist on the shell that has, 0ev, 4ev, 6ev and 7ev, and cannot exist in between energy levels as it cannot exist on say 4.7ev. And cannot exist on any other shell.

Let's say the atom starts at 0ev, or "The ground state".
How does an election go from the ground state to an even level?. First, a photon with 4ev must strike the election, and then the election will absorb the photon, thus causing the election to be removed from the ground state and instead on the EV level of 4ev.

Valence electrons are electrons that are highly important as it is the outermost shells of the atom, and an atom's outer shell is the most important in chemistry.
A full Valence shell has 8 electrons or 4 pairs.

Chemistry pt. 4: Ions

 Let's take Carbon, one atom of Carbon has 6 Protons and if it is a neutral Carbon it will have 6 Electrons, to get Ion you need to have an unequal amount of Protons and Electrons.

So let's take a Carbon with one less Electron than a Proton, then it would be a C+1 Proton atom. Now let's take a Carbon atom with one more Electron than Proton (5 Protons, 6 Electrons.
Well since we have only 5 Protons and not 6, the element we are dealing with is now Boron, neutral Boron would have 5 Protons and 5 Election, but in this case, the Boron has one extra electric charge (on extra Proton, 6 Protons and 5 Electrons), you could write it as B-1 or Boron minus 1 Electron, this would be a Boron Ion.

Now let's take Platinum, it has a mass number of 195 (Protons and Electrons added together) and contains 74 Electrons, we want to find what its charge is.
On average Platinum has 78 Protons, so if we do 74 - 78, we are left with 4, meaning that there are 4 more Protons than Electrons in a Platinum atom, so it would be a positively charged Atom,
the name of this type of atom is a Cation which is a positive Ion, and the inverse or negatively charged atom is an Anion. 

But let's say we also need to figure out how many Protons and Neutrons it contains and what is its charge, we already know that Platinum has 78 Protons, and an atomic mass number is its Protons plus the Neutrons, all you have to do is minus 195 - 78 which would get you to 117, so the amount of Neutrons in a Platinum atom is 117.

Let us take a Calcium atom, Calcium has 20 Protons, and for this example let us say that this atom has 18 Elections, if you know, Electrons give a negative charge, and Protons give a positive charge, so if we do 20 (protons) minus 18 Elections, we get 2, so there are two more Protons, so this Calcium atom has 2 extra Protons, if an atom has an equal amount of Protons and Electrons, they are a neutral atom, but since there is two extra Protons this specific Calcium atom is a positive Calcium atom or C+2.
The "+2" means plus two Protons.

If we do a Calcium atom with 20 Protons, 21 Electrons and 17 Neutrons, well 20-21 is 1, so that extra one, is minus since Electrons are minus charges, this atom would be a Calcium with a negative charge or C-1, notice how the Neutrons did not matter in the calculations, as Neutrons have no impact to the calculation of Ions.

Chemistry pt. 3: Average atomic mass

For things at this scale, we need a unit of measurement, the name of this is the "Atomic mass unit" or AMU, the more modern version is the: "Unified mass unit", and written as U.

The weight of this mass unit is 1.660540 * 10^-27kg, for scale, it is a 0. With 26 zeros behind that, the mass of a Proton is approximately 1U, and one Neutron is also approximately 1U, it turns out a Proton is slightly heavier with a weight of 1.007U, and a Neutron is approximately 1.008U, an Electrons mass is instead very light compared to both, being 1/2000 the mass of a Neutron or Proton.

Thus the main mass is the Protons and Neutrons in the nucleus. 

Let's take an element: Hydrogen, let's figure out the mass of a Hydrogen atom, which is one Proton, since the amount of Protons is shown on the periodic table, it is very easy to say that Hydrogen has one Proton.

When we talk about variations and different versions of an atom, we call those Isotopes, All isotopese follow the "parent" element, as all Isotopes of that element have the same number of Protons, in this case, it is a single Proton from Hydrogen atom, but due to it being a Isotope, it has different numbers of Neutrons.

Notice how the element is written in the periodic table, it has a number on the top, the amount of Protons, the element name in the middle, and the bottom is the average weight of that atom, on the Hydrogen atom, the weight is 0.008 which is the for that element found on earth.

Chemistry pt. 2: Isotopes

iMost of the mass in an atom comes from the amount of Protons and Neutrons in its nucleus. 

While every element is determined by the amount of Protons in its atom, the element Xenon is 54, and Copper is 29, but Neutrons are important too, not all atoms with different numbers of Neutrons are named "Isotopes". 

The sum of Neutrons and Protons in an atom is its "Mass number". For example: 
A is its Mass number, C is the Chemical Symbol and Z is the Atomic number:

                                                          A
                                                            C
                                                          Z

Let's take the element Silver or (Ag), you would need to add the amount of Protons and Neutrons together (47 Protons, 61 Neutrons) add them together you would get:

                                                         108 (total Protons and Neutrons)
                                                                Ag (chemical symbol)
                                                          47 (atomic number

Notice how we are filling in the numbers above like A, C and Z letters from the above diagram.

Another way to depict it is:

                                                            C-13 (carbon 13)

Which is carbon (C) and 13 is the atomic number, so for another one:

                                                            Au-78 (gold)

See the correlation, the element and then a hyphen or - symbol, then its atomic number.

But it is not all that easy, as atoms that have the same element can have different numbers of Neutrons, and these are dubbed as "Isotopes" which is the topic of today's post, as Isotopes have different numbers of Neutrons, they also have different mass numbers.

Ill just reuse this:

                                                          108 (total Protons and Neutrons)
                                                                Ag (chemical symbol)
                                                          47 (atomic number

Now, if you're told to figure out how many Neutrons does this element have, first just take the total mass (108) and minus 47 (the atomic number). which will give you the result of 61 Neutrons, or "108 - 47 = 61".

Now let's do it a little differently:

                                                         Pt-195

Now, you have to do it differently, so "Pt" is the element platinum, and platinum has 78 Protons, so all you have to do (again), is take the mass number in this case is 195, and minus it by 78 which it's amount of Protons, and "195 - 78 = 117", or 117 Neutrons.

Chemistry pt.1: Atoms

Everything is made out of Atoms, such as Protons, Neurons, and Electrons, they make up everything, the water we drink, the air we breathe, and the things we use every day is made out of atoms, even though they all look completely different, but they are all made out of Proton, Electrons, and Neutrons, so what are they:

At the centre of an Atom, we have a Nucleus comprised of Protons and Neutrons, outside the Nucleus we have the "Neutron cloud", which is where you will find Electrons. 

An Atom Neutron cloud can be 100,000 times larger than its Nucleus.

Protons have a positive charge of +1, while Electrons have a negative charge of -1, these charges cancel out as they are +1 and -1 charges, while the Neutron itself is neutral in charge.

We use the "Unified Atomic Mass Unit" as a way of saying the mass, the name of this form of measurement is usually shorted to the letter "U" so Protons and Neutrons have the mass of 1u, while Electrons have the mass of 0.0005u which makes them roughly 2000 times smaller than the Proton and Neutron, meaning all the mass from the Atom resides in the Nucleus.

Everything is an atom, but they are not the same, there are many different types of atoms, named Elements, each with their own special physical and chemical properties, many are commonly used, such as Oxygen, Carbon, Gold, and Silver.
Some might not be so familiar like Bismuth, Osmium and Xenon, a particular element is identified by the amount of Protons in its atom, known for its Atomic number or "Z", for example, Helium is atomic number 2, meaning every helium atom has two protons, and another is Iron its atomic number is 26 so they have 26 Proton, also the amount of Protons can also tell us how much

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