Answer:
2.56g of H₂S
Explanation:
The reaction of H₂S with Pb(CH₃COO)₂ is:
H₂S + Pb(CH₃COO)₂ → 2 CH₃COOH + PbS
Where 1 mole of H₂S produce 1 mole of PbS
18.00g of PbS (Molar mass: 239.3g/mol):
18.00g of PbS ₓ (1mol / 239.3g) = 0.0752 moles of PbS
As 1 mole of PbS is produced from 1 mole of H₂S, moles needed of H₂S are 0.0752
As molar mass of H₂S is 34.1g/mol, mass in 0.0752moles is:
0.0752 mol H₂S ₓ (34.1g / mol) = 2.56g of H₂S
