The language of chemistry

Introduction Chemists (scientists studying chemistry) will use certain terms or symbols to describe or represent certain terms. These can be very useful in many instances and most of the terms are fairly simple to remember.

Ions

Simple Ions In simplest terms, an ion is a particle that possesses a charge either positive or negative. This happens when a particle reacts in certain ways. When this happens the atom tries to get the same number of electrons as the nearest noble gas. Another good thing to know is that, in science, opposites attract. An example of this can be found in electroplating copper. In this process when you charge a piece of iron negatively, the positive ions of copper sulfate attach and plate the iron. An example of this can be found in electroplating copper. In this process when you charge a piece of iron negatively, the positive ions of copper sulfate attach and plate the iron. Another important fact to remember is that when a nonmetal gets a charge its name has an ‘ide’ on it. Some example could be oxide, hydroxide, fluoride and chloride.

What would this look like? This is a positive ion of helium. You can tell this due to the fact that it has more protons that electrons This is a negative helium ion. You can tell this because it has more electrons than protons. Just so you know you helium already has a full outer shell and therefore realistically should be an ion It is also a gas and therefore would not create ionic bonds

How does a particle get a charge and how is it written? A particle gets a charge when it loses or gains an electron. To write this you would put the particle and then in hypertext how many electrons or protons it would need to become neutral. An example is sulfur. S 2– means that it is a positive ion Another one is Mg 2+. This is negative magnesium.

Polyatomic Ions In the last part I had explained in simple terms how ions work for single atoms. However, this is not always the case. Polyatomic ions are ions with more than one atom in them.

How is this written? Polyatomic ions are written out just like all other ions. For example I will use nitrate. Nitrate written out normally is NO3 But the positive form is written out NO3 - If there is no number before the minus then it is as there was a one there.

Transition metal ions. Unlike all other ions, transition metal ions do not always reach the same number of electrons as the closest noble gas. These metals usually will lose one, two or three electrons.

Ionic Compounds

Writing Formulas Whenever ions combine to create compounds, they have to react in a way that makes the compound neutral. To do this you have to find out how many electrons each ion needs to gain or lose in order for it to become neutral. Once you have done that, try to multiply the atoms in by different numbers in order to see if they become neutral

Example Un balanced: Cr 3+ +SO4 2- = CrSO4 1- Balanced: 2Cr 3+ +3SO4 2- = Cr2(SO4)3 If you know the outcome of the reaction then it makes it a lot easier.

Brackets Brackets are used in chemistry to represent how many of certain atoms are in a compound. An example of this is: Cr2(SO4)3 In this case this means that there are three sulfur atoms and twelve oxygen atoms

Writing names When writing the names of an ionic compound you should include the type of atoms that is used. An example is Fe(OH)2 In this example if you know that there was two hydrogen atoms needed to in order to balance to iron then the iron must have a charge of +2. Therefore the compound would be written, Iron (II) hydroxide.

Molecules

Matter Here is a diagram to help you to remember the main different types of matter.

What are Molecules? Molecules are particles made up of multiple atoms. The most common form of molecules are diatomic molecules. The air that we breathe is made up of two different kinds of diatomic molecules It is made up of O2 and N2 (oxygen gas and nitrogen gas)

Covalent bonds When non-metals come together and bond they don’t become ionic, instead they become covalent. In a covalent bond, electrons are shared and not given or taken. Through sharing electrons they can gain the same electron configuration as a noble gas

Writing out Molecules When writing out molecules in words you use prefixes before the name of the element. Some of these are mono for 1, di for 2, tri for 3, tetra for four, pent for 5 and hexa for 6 An example of this could be dinitrogen pentoxide (N2O5)

States of Matter

The basics of the states of matter The states of matter are the different state in which matter can be found. The three main ones are gas, liquid and solid In chemical equations these states are written as (l) for liquid, (g) for gas and (s) for solid

Solutions

What is a solution? A solution is a substance where a solvent has had a solute dissolve into it A solvent is a liquid in which something will dissolve and a solute is something that is dissolved in it.

Some examples of different solutions

Concentration of a solutions

Dissolution Dissolution is when a solid is dissolved into a liquid This is what it looks like on an atomic scale (this is with water and table salt).

References All information used came from the course book