JEE Main levelNumerical answerDifficulty 2 of 3ec09
During discharge of a lead storage battery, 0.5 mol of electrons flows through the external circuit. The mass of HX2SOX4 consumed (in g) is. (Molar mass 98 g mol−1)
Numerical answer type, answer in g, tolerance 0.5.
Answer: 49 g
Overall: Pb+PbOX2+2HX2SOX42PbSOX4+2HX2O, which transfers 2 mol electrons. So 1 mol HX2SOX4 per mole of electrons. 0.5mol×98=49g.