Question

In an experiment, 1.0g CaCo3 on heating evolved 224ml of Co2 at STP. what mass of CaO is formed?

Answer 1

Dear Student,

◆ Answer -

Mass(CaO) = 0.56 g

◆ Explanation -

Moles of CaCO3 are given by -

Moles(CaCO3) = W / M

Moles(CaCO3) = 1 / 100

Moles(CaCO3) = 0.01 mol

Moles of CO2 are given by -

Moles(CO2) = V / V0

Moles(CO2) = 0.224 / 22.4

Moles(CO2) = 0.01 mol

Thermal decomposition of calcium carbonate is as follows -

CaCO3 --> CaO + CO2

From this,

1 mol CaCO3 => 1 mol CaO + 1 mol CO2

0.01 mol CaCO3 => 0.01 mol CaO + 0.01 mol CO2

Now, mass of CaO formed is -

Mass(CaO) = n × W

Mass(CaO) = 0.01 × 56

Mass(CaO) = 0.56 g

Hence, 0.56 g CaO is formed in the reaction.

Hope this helps you..