Problem 70P

Lead is found in Earth's crust as several lead compounds. Calculate the mass (in kg) of each compound that contains 1.0 × 103 kg of lead.

(a) PbS (galena)

(b) PbCO3 (cerussite)

(c) PbSO4 (anglesite)

Solution 70P

Here, we have to calculate the mass of each compound that contains 1.0 × 103 kg of lead.

Molar mass of Pb = 207.2 g/mol

(a)PbS

Pb2+ + S2- ------->PbS

Molar ratio =1:1

Molar mass of PbS =239.3 g/mol

Mass of PbS = 1000 g x = 1154.9 g = 1.1549 Kg

Thus, mass of PBs is = 1.1549 Kg

(b) PbCO3 (cerussite)

Pb2+ + CO32- ------->PbCO3

Molar ratio =1:1

Molar mass of PbCO3 =267.21 g/mol

Mass of PbCO3 = 1000 g x = 1289.62 g = 1.289 Kg

Thus, mass of PbCO3 is = 1.289 Kg

(c) PbSO4 (anglesite)

Pb2+ + SO42- -------> PbSO4 (

Molar ratio =1:1

Molar mass of PbSO4 =303.26 g/mol

Mass of PbSO4 = 1000 g x = 1463.61 g = 1.463 Kg

Thus, mass of PbSO4 is = 1.463 Kg