Question

Given that the relative molecular mass of copper oxide is 80, what volume of ammonia (measured at STP) is required to completely reduce 120g of copper oxide? The equation for the reaction is:

\[\ce{3CuO + 2NH3 → 3Cu + 3H2O + N2}\]

Answer 1

\[\ce{3CuO + 2NH3 → 3Cu + 3H2O + N2}\]

The molecular mass of 3Cu 3CuO = (240)g

Molecular mass of 2NH₃ = 2 × 22.4 = 44.8 dm³

Molecular mass of 3Cu = (192)g

240 g of CuO requires 44.8 dm³ of NH₃

∴ 120g of CuO will require `(120 xx 44.8)/240`

= 22.4 dm³