General Understanding Of Compounds, Chemical Formula And Molar Mass

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Here, we will explain the general understanding of Compound, Chemical Formula and Molar Mass.

General Understanding of Compounds

As you know the definition of compound is:

Def of compounds - two or more elements "chemically combined" in a fixed mass (therefore fixed number) ratio.

In general, there are two types of compounds, Molecular compounds (MC) and Ionic compounds (IC). For our purposes here, we can simply say that

1) Molecular compounds - two or more non-metals elements/atoms coming together
2) Ionic compounds - one type of metal element/atom and one type of non-metal coming together

Actually, how you determine if a set of elements coming together is a MC or IC entails more understanding than stated above. These details will be discussed or taught in a separate location.

Chemical Formula

A question one may have is, How many atoms of each element are coming together to form these compounds?

Chemists have a short hand method to show this called Chemical Formulas.

Def Chemical Formula - a way of showing what elements are coming together and how many of each.

The chemical formula uses the chemical symbol of each element and a subscript that indicates how many atoms of each element are coming together to form the compound. Here are two examples including their chemical name:

1) Na₁Cl₁ - Sodium chloride (an Ionic compound).
2) C₁O₂ - Carbon dioxide (a Molecular Compound).

For our purposes here, you can say that:

1) In one ionic compound's base unit (or particle) of Na₁Cl₁, there is one atom of Na and 1 atom of Cl (not actually correct but will explain elsewhere).
2) In one molecular compound's base unit (or particle) of C₁O₂, there is one atom of C and two atoms of O. (this is actually correct).

This is very important to understand in chemistry because the chemical formula can be seen as analogous to words (combinations of letters to represent "something") in languages.

Molar Mass - Expanding Mole Concept of Massing to Any substance

As of this point, you have learned how to do One Step Mole Calculations for Massing Elements (Mole Concept - Basic and Massing).

With the knowledge that there are other substance in the world besides elements (i.e. compounds), we want a simple set of words that we can use for any substance. This is called the Molar Mass.

Def Molar Mass: the mass of one mole of any substance

So to calculate this mass you simply find the atomic mass of the element and multiply it by the subscript (number of atoms of that element in the compound, see above discussion) and repeat for each of the elements in the compound. Add them all up and get the total mass you need to weigh/mass out to get a mole of that compound (i.e. Molar Mass).

It is very important to understand that the Molar Mass is a conversion factor between the mass (in g) of the substance and 1 mole of that substance. It is written as:

44g C₁O₂
1 moleC₁O₂

Molar Mass ARE NOT SIMPLY A MASS !!!!

These conversion factors will be used in Mole Concept of Mass Calculations of any type. How you actually do these calculations and an example of the work in elsewhere (e.g. the accompanying links).

Final Note: There are a lot of different specific names for Molar Mass depending on which substance you are looking at. The list will not be provided here but will be highlighted in another location.