Question

The original sample is not pure,but is contaminated with a thermally stable compound.Will the reported mole ratio of CaO to CO2 be too high ,too low, or unaffected? Explain.

Answer 1

The original sample is not pure, but is contaminated with a thermally stable compound. Will the reported mole ratio of CaO to CO2 be too high, too low, or unaffected? Explain.

Solution:

We can say that impurity is CaCO3.

CaCO3 à Cao+CO3

As we know CaCO3 decomposes when heat is applied. This original sample is thermally stable.

When heat is applied CO2 will be generated and only CaO will remain as impurity.

Reported mole ratio of CaO to CO2 will be too high because we will be counting the mass of the impurity as if it was mass of CaO but CO2 has left the system.