The Avogadro's Law
So atoms of each element have a different mass. For example, the average iron atom will have a mass of 55.8 amu. Remember that 1 amu is very small, about the mass of a proton or neutron. Because balances in the chemistry lab don't measure in amu, we are going to need to scale this up to something they domeasure: grams. Just how many amu are equal to 1 gram? The answer to this is a very, very large number: 6.02 x 10^23. That is 602,000,000,000,000,000,000,000. I don't even know what that number is called. That's okay, because this number has its own special name (kind of like 12 has its own special name: dozen). Its special name is Avogadro's number, which is named after this guy. Avogadro's number is more commonly called the 'mole.' The mole is just a large number, a way to count how many of something you have, and obviously a very large number. It is always equal to 6.02 x 10^23. It is the number of amus in 1 gram, so 1 mole of amus equals 1 gram.
- Krysta Coleen Matias