Calculate the mass of calcium carbide formed by the action of carbon on calcium oxide weighing 16.8 g

Calculate the mass of calcium carbide formed by the action of carbon on calcium oxide weighing 16.8 g, if the yield is 80%.

Given:

m (CaO) = 16.8 g

w% (CaС2 practical) = 80%

To find:

m (CaC2) -?

Decision:

2CaO + 4C = 2CaC2 + O2, – we solve the problem, relying on the composed reaction equation:

1) Find the amount of calcium oxide that has reacted:

n (CaO) = m: M = 16.8 g: 56 g / mol = 0.3 mol.

2) We compose a logical expression:

if 2 mol CaO gives 2 mol CaC2,

then 0.3 mol of CaO will give x mol of CaC2,

then x = 0.3 mol.

3) Find the theoretical carbide yield:

m (CaC2) = n * M = 0.3 mol * 64 g / mol = 19.2 g

4) Find the actual mass of the resulting carbide:

m (CaC2) = 19.2 g * 0.8 = 15.36 g

Answer: m (CaC2) = 15.36 g.