Chemistry June 11th - What is a mole and Avogadro's Law

Let's start with the mole....

A mole is just a standard unit of measure that allows chemists to work with the microscopic world (atoms) in macroscopic terms; a name for a certain number of things.  So, just as a dozen means 12 of something, a mole means 602 hexillion or 6.02 x 10E23 of something.  This number is referred to as Avogadro's number because it came about as the result of his hypothesis about the distinction between molecules and atoms when combining different elements, although he did not actually determine the number.

Avogadro's hypothesis provided a way to determine certain characteristics of a gas if temperature and pressure were constant then volume and the amount of gas had a direct relationship.  This relationship is expressed as n1/v1 = n2/v2 where temperature and pressure are constant and n = amount of gas and v = volume of gas.  So let's take oxygen for example - O2. 2 atoms of oxygen are 32 moles (16 is the atomic mass x 2).  If you know that you have 50.0 grams of oxygen and that is 48 liters, you can use the formula to converts gram to moles and determine how many grams of oxygen you would need if you wanted a volume of 60 liters.  I am not going to do the math because I would honestly just be copying from a YouTube demonstration but this gives relevance to why moles and the Avagadro's Law are important for the many chemical reactions that run our world.  Especially when Green Chemistry principles for the conservation of raw materials and reduction of waste (zero waste ideal!) are a standard to work toward.  Chemists can determine the optimal ratio of reactant for a chemical reaction so the all products are fully used.

I am so grateful for the brilliant people who make Green Chemistry a reality in our lives and am hopeful they will make the ONLY way for chemical processes to be used in the industrial consumer based world we live in.