Answer: B
Charge =0.50×9650=4825 C, so n(e−)=4825/96500=0.05 mol. The cell reaction transfers 2 electrons and forms 2 mol PbSOX4 (one on each plate), so 1 mol PbSOX4 forms per mole of electrons. Molar mass of PbSOX4 =207+32+64=303 g/mol, so the mass =0.05×303=15.15 g.