Question

A 40.80 gram sample of copper is heated in the presence of excess sulfur. A metal sulfide is formed with a mass of 51.09 g. Determine the empirical formula of the metal sulfide.

Answer 1

Cu₂S

Step-by-step explanation:

From the question,

Cu S

Mass: 40.80 g 51.09-40.80 = 10.29 g

Mole ratio: 40.80/63.5 10.29/32.1

0.64 : 0.32

Divide by the smallest,

0.64/0.32 : 0.32/0.32

2 : 1

Therefore,

Empirical formula = Cu₂S.