Answer:
The mass of CuCl is 214.2 grams
Step-by-step explanation:
Step 1: Data given
Mass of HCl = 78.9 grams
Molar mass HCl = 36.46 g/mol
Molar mass of CuCl = 99.0 g/mol
Step 2: The balanced equation
2CuCl + H2S → Cu2S + 2HCl
Step 3: Calculate moles HCl
Moles HCl = mass HCl / molar mass HCl
Moles HCl = 78.9 grams / 36.46 g/mol
Moles HCl = 2.164 moles
Step 4: Calculate moles CuCl
For 2 moles CuCl we need 1 mol H2S to produce 1 mol Cu2S and 2 moles HCl
For 2.164 moles HCl we'll need 2.164 moles CuCl
Step 5: Calculate mass CuCl
Mass CuCl = moles CuCl * molar mass CuCl
Mass CuCl = 2.164 moles * 99.0 g/mol
Mass CuCl = 214.2 grams
The mass of CuCl is 214.2 grams