Marvin Da Mole!  Our Hero 
1.      Calculate the mass of                                                                                                                   
a) 2.00 moles of water, H2O
b) 4.38 moles of chlorine, Cl2
c)  0.025 moles of ammonia, NH3
d)  1.8 moles of oxygen, O2
2.  Calculate the number of moles in
a)  25 g of helium, He
b)  12.5 g of methane, CH4
c)   0.364 g of iodine, I2
d)   40.0 g of sodium, Na
3.  Calculate the number of particles in
a)  2.50 moles of Neon, Ne
b)  0.050 moles of iron, Fe
4.  Calculate the number of moles in
a)  9.03 X 1023 atoms of Cu
b)  3.76 X 1025 molecules of SO2
c)  8.6 X 1018 electrons
5.    Calculate the number of molecules in 
a)   12.5 g of nitrogen, N2 
b)   0.76 g of ammonia, NH3 
c)   0.60 g of hydrogen, H2 
6.   Calculate the mass of
a)  4.25 X 1024 atoms of C
b)  6.02 X 1021 molecules of H2O
c)  one trillion atoms of Zn
d)  one atom of U