Example #2 of mass to moles conversion
Q: How many grams of N2(g) are produced when 100g of N2H4 react?
1) Write out the reaction and balance it out. Sometimes the equation is already given.
2N2H4(l) + N2O4(l) —-> 3N2(g) + 4H2O(g)
Next, start with 100g of N2H4 (reactant) MM= 32.05g/mol.
You’re solving for mass of N2(g) (product) MM= 28.0g/mol.
2) Convert. *see “mass to moles conversion” post*
100g N2H4 x (1mol. N2H4/32.05g) x (3mol. N2/2mol. N2H4) x (28.0g/1mol. N2)= 131g of N2(g). Done.