Question

What is a mole? How is it related to Avogadro number?

Answer 1

A mole is just another unit to describe how many things there are, like a dozen. You can say you have a mole of eggs just like you say there are a dozen eggs. The difference is that a mole means 6.02214199 X10^23 things instead of 12. Usually, though, a mole refers to the amount of atoms in a substance.

Answer 2

one mole is the amount of substance that has the same number of particles found in 12.000 grams of carbon-12. 

1 mole = 6.023 x 10^23 particles