Quiz 1: Quantitative Chemistry

1 mol of  = 9 mol of O atoms

Number of O atoms = 

Apply the Avogadro's law: V proportional to n

Stoichiometric ratio of  is 2 : 2 (or 1 : 1)

Expected volume of  produced from CO = 5 

Stoichiometric ratio of  is 1 : 2

Expected volume of  produced from  = 2 x 2 = 4 

SInce  gives smaller volume of  produced, therefore  is limiting reactant and the maximum volume of  produced is 4 

Number of molecules is proportional to amount

Amount of  in choice 1 = 1.4/28 = 1/20 mol

Amount of  in choice 2 = 1.4/22.4 = 14/224 = 1/16 mol

Amount of  in choice 3 = 

Amount of  in choice 4 = 1.4 mol

Hence choice 4 has the greatest amount of  and therefore the greatest number of  molecules.

Empirical formula of 

Empirical formula of 

Empirical formula of 

Empirical formula of 

Hence the empirical formula with the largest mass is 

Applying the equation 

Pressure double => 

Volume double => 

Assume the given volume is interms of 



Amount of  = 25.0 x 0.200 = 5.00 mol

Stoichiometric ratio of  is 2 : 1

Amount of HCl = 5.00 x 2 = 10.0 mol

Concentration of HCl = 0.200 

Volume of HCl required = 10.0/0.200 = 50.0 

Assume the mass is given in grams

Stoichiometric ratio of  is 1 : 2

Amount of  = 1600/160 = 10 mol

Expected amount of Fe formed from  = 2 x 10 = 20 mol

Stoichiometric ratio of C : Fe is 3 : 2

Amount of C = 144/12 = 12 mol

Expected amount of Fe fromed from C = 12 x (2/3) = 8 mol

Since carbon gives the least amount of Fe, therefore carbon is the limiting reactant



Maximum yield of iron = 8 x 56 = 448 kg

1 mol of  contains 2 mol of  ions

0.20 mol  of  = 0.40 mol of  ions

Volume = 100  = 0.1 

Concentration of  = 0.40/0.1 = 4.0