Question

Freon – 12, CCl2F2, is prepared from CCl4 by reaction with HF. The other product of this reaction is HCl. Outline the steps needed to determine the percent yield of a reaction that produces 12.5 g of CCl2F2 from 32.9 g of CCl4. Freon – 12 has been banned and is no longer used as a refrigerant because it catalyzes the decomposition of ozone and has a very long lifetime in the atmosphere. Determine the percent yield.

Answer 1

CCl₄ + 2 HF $\rightarrow$ CCl₂F₂ + 2 HCl

1mole of CCl₄ is responsible for production of 1 mole of CCl₂F₂

Moles of CCl₄ = $\frac{32.9}{153.8}$ = 0.254 moles

Theoritical yield of CCl₂F₂ formed = 0.254× 120.9 = 30.81g

%yield = $\frac{12.5×100}{30.81}$

= 40.57%