Question

Calculate the grams of oxygen produced if 16.0 grams of lithium chlorate are completely decomposed by heating.

Answer 1

The equation of this reaction is

2LiClO₃ --> 2LiCl + 3O₂
if lithium chlorate is 16.0 grams;
You can find the amount of substance:
n(LiClO₃) = m(LiCl)/M(LiCl);
M(LiClO₃) = 7+35.5 + 16 * 3 = 90.5 g/mol;
n(LiClO₃) = 16 g / 90.5 g/mol = 0.18 moles
amounts of substances are related
n(LiClO₃) : n(O₂) = 2 : 3;
n(O₂) = n(LiClO₃) * 3 / 2 = 0.27 moles;
m(O₂) = n(O₂) * M(O₂);
M(O₂) = 16 * 2 = 32 g/mol;
m(O₂) = 0.27 moles * 32 g/mol = 8.64 g;
So weight of oxygen is 8.64 g.