1) Mole: Within a mole there are ALWAYS 6.023 x (10x23) particles within the mole and then depending on the element the molarity maybe smaller or larger.
2) GFW or Molar Mass is the total atomic mass of the compound
How to locate the GFW of a compound
Using a Periodic table locate the atomic mass of each of the elements included within the compound
If you have a compound Triazane or N3H5
First find the atomic numbers of each element
N or Nitrogen has an atomic mass of 14 
H or Hydrogen has an atomic mass of 1
Then multiply the elements by the subscript number given and add them together
3(14) + 5(1) = 42 + 5 = 47
The GFW of 
Triazane or N3H5 = 47
3) Yield is the amount produced. In an equation the percentage yield is the percentage produced