Question

Potassium chlorate will react by itself (when heated) to form solid potassium chloride and oxygen gas. If you heat 60.0 g of potassium chlorate and you obtain 20.0 g of oxygen gas, what is your percent yield?

Answer 1

Ans :

The balanced equation is given as :

2KClO3 = 2KCl + 3O2

Mol potassium chlorate = mass / molar mass

= 60.0 g / 122.5 g/mol = 0.489 mol

2 mol compound gives 3 mol oxygen

so 0.489 mol compound will give : ( 0.489 mol x 3 mol) / 2 mol

= 0.734 mol oxygen

theoretical mass of oxygen = mol x molar mass

= 0.734 mol x 31.999 g/mol

= 23.5 g

percent yield = ( theoretical mass / actual mass ) x 100

= (20.0 g / 23.5 g ) x 100

= 85.1 %