Two electrolytic cells containing $AgNO X_{3}$ and $AuCl X_{3}$ solutions are connected in series. When 2.158 g of silver is deposited in the first cell, the mass of gold deposited in the second cell (in g, two decimals) is. (Ag = 107.9, Au = 197)

Numerical answer type, answer in g, tolerance 0.01.

Answer: 1.31 g

Same charge passes through both. Moles of electrons

= 2.158/107.9 = 0.0200

Au X^{3 +}

needs 3 electrons per atom, so moles of Au

= 0.0200/3

and mass

= (0.0200/3) \times 197 = 1.313 g \approx 1.31 g