Two cells, one containing AgNO3 and the other SnCl2, are connected in series and a given quantity of electricity passes through both. If 2.00 g of silver is deposited in one cell, how many grams of tin are deposited in the other?
February 20th, 2023
The mass of tin deposited is 1.1 g.
The steps involved are:
1. Write the balanced equation.
2. Use conversion factors to convert mass of Ag → moles of Ag → moles of Sn → mass of Sn
Step 1
The balanced equation for a galvanic cell is
2 × [Ag⁺ + e⁻ → Ag]; ##E°## = +0.80 V
1 ×[Sn →Sn²⁺ + 2e⁻]; ##E°## = +0.14 V
2Ag⁺ + Sn → 2Ag + Sn²⁺; ##E°## = +0.94 V
This equation tells you that, when you force electricity between two cells in series, the moles of tin deposited are twice the moles of silver.
Step 2
Mass of Sn = 2.0 g g Ag × ##(1″mol Ag”)/(107.9″g Ag”) × (1″mol Sn“)/(2″mol Ag”) × (118.7″g Sn”)/(1″mol Sn”)## = 1.1 g Sn (2 significant figures)