Question

What mass of Ag will be produced from 3.7 g of Ni in the following reaction?

__Ag(NO3) + __ Ni → __Ni(NO3)2 + __Ag

Answer 1

Balanced equation:
2 AgNO3 + Ni → Ni(NO3)2 + 2 Ag

1) Moles of Ni: n(Ni) = 3.7 g / 58.69 g·mol⁻¹ = 0.0630 mol

2) From the equation 1 mol Ni → 2 mol Ag, so n(Ag) = 2 × 0.0630 = 0.1260 mol

3) Mass of Ag: m = 0.1260 mol × 107.87 g·mol⁻¹ = 13.6 g

With the given data (2 sig figs) you could report this as 14 g Ag.