Answer to Question #115945 in General Chemistry for Dom

Question

When copper is heated with an excess sulfur, copper(l) sulfide is formed: in a given experiment, 1.50 g of copper was heated with excess sulfur to yield 1.63 g copper(l) sulfide. What is the percent yield?

Answer 1

2Cu + S -->Cu₂S;

Theoretical mass of Cu₂S :

m_theor(Cu₂S)=m(Cu)*Mr(Cu₂S)/(2*Mr(Cu))=1.5*160/(2*64)=1.875 g;

percent yield=(1.63/1.875)*100%=86.93 %

Answer: 86.93%