Atoms make up everything from you to a rock. When there is only one atom it's called an element, but when more join the atom party it's a compound. An atom contains protons (positively charged), neutrons (no charge, or neutrally charged), and electrons (negatively charged). In an atom the protons and electrons should be the same amount so as to acquire a neutral charge, if there is a charge due to more or less electrons than the atom will be called an ion. Cation (Cats have paws there fore positive, memory trick given by Miss. York) which are positive, and anions which are negative. Now that you know what an atom is let's see how they are arranged on the periodic table.
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You can't see very well on this periodic table, but above each letter in the little boxes there is a number. This number states the amount of protons, and therefore also electrons, in an atom. Protons do not change, because that would make it a different element. The number below the letters, also hard to see, is the atomic weight of the element. The atomic weight includes protons and neutrons (electrons don't weigh enough to register) which both equal 1 (not 100% sure what it's measured in, maybe moles). The reason decimals are used is because the amount of neutrons can differ from atom to atom. The number listed on the periodic table is an average of atoms. Now let's break out of the box and look at the big picture of the periodic table.
The periodic table is ordered in rows (periods) and columns (families). The basic family names are as follows Alkali metals (1orange), Alkaline earth metals (2yellow), Transitional metals (middle section), Other metals (kind of grayish-green), Metalloids (a different green in a staircase pattern), Non-metals (lime green), Halogens (7light blue), and noble gases (8blue with a bit of lavender). While there are more names within the transitional metals and other areas these are the basics. Elements within the same family have similar properties and reactivity. What family an element is in shows the amount of valence electrons (do not count transitional metals when counting the family number) or electron on the outer electron shell. The rows show the number of shells. The first shell can hold 2 and the second and third can hold 8 each. Once it gets to the transitional metals I am not certain enough to try teaching others I would suggest trying a more accurate site.
As I mentioned earlier the electrons in an atom are arranged in shells. The outer shell determines how that element will react with others to make a compound. As my teacher said to be truly happy an atom must have a full valence shell (outer shell). To make a full outer shell there are two basic types of bonds. When two non-metals (elements on the left of the staircase pattern on the periodic table) bond it's called a covalent bond. In these bonds the non-metals decide to share electrons. My memory trick for this is covalent bonds cooperate. When a metal and a non-metal bond it's called an Ionic bond. In an ionic bond an electron is transferred from one atom to another. For example Sodium (Na) needs to lose one electron to have a full outer shell and Chlorine (Cl) needs to gain one electron to have a full outer shell, so Sodium gives one of it's electrons to chlorine. Ionic compounds form stronger bonds than covalent.
When making a simple compound remember that the product (what you are making) is usually neutral. For example Magnesium (Mg) and Bromine (Br) make MgBr2(subscript), because magnesium has a charge of 2 (second family on the periodic table) and Bromine has a charge of negative one (one away from group 8). The metals are positive and non-metals are usually negative. Now that you know how to make basic compounds, how do you name this new concoction.
To name a compound first you must determine whether it is Ionic or Covalent. If it's Ionic all you have to do is put ide after the non-metal. For example Magnesium oxide, or Mercury (II) Fluoride. If the metal can have two or more different charges like Mercury (II) Fluoride than the charge of the metal should be put in brackets as shown. In covalent bonds the number of each element used should be indicated with a prefix.
Prefixes
Mono-1
Di-2
Tri-3
Tetra-4
Penta-5
Hexa-6
Hepta-7
Octa-8
Nona-9
Deca-10
You will probably not be using anything after deca. If there is only one of the first non-metal than mono does not need to be put, but it should for the second non-metal. If there is only one oxygen than it is monoxide. You do not put two O's. Now that you know the basics of making and naming compound let's get into the complexities of covalent compounds and diatomic molecules.
For making basic covalent compounds the easiest way is to use the stock method. For example Carbon needs 4 electrons for a full shell and Sulphur needs 2, so together they make Di Carbon Tetra Sulphide. All you do is switch the number of electrons that both electrons need to form a full shell. In some elements two of the same element can form a compound, these are called diatomic molecules. The following elements can form diatomic molecules Hydrogen (H), Oxygen (O), Fluorine (F), Bromine (Br), Iodine (I), Nitrogen (N), and Chlorine (Cl). One way to remember this is HOFBrINCl the clown.
Next week (or maybe later this week) we will be getting into the different reaction types, and how to write them, and a brief acids and bases lesson. There may also be a quick tutorial on how to count the amount of atoms in an equation. If there is a subject that you would like to learn about please leave a comment below.
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Due to the sheer length of today's post I am saying I am eight behind, and counting this as yesterday's post as well.
Doctor Who Quote
Two quotes from the second doctor.
The Doctor: Officially I'm here quite unofficially.
The Doctor: Logic, my dear Zoe, merely enables one to be wrong with authority.
I would like to comment on this blog but since I fell asleep 10 times while reading it I don't know what to ...........zzzzzzzZZZZZZZZZZZZZZZZZZ
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