Question

Calculate ΔHrxn for the following reaction:

BaO(s)+CO₂(g)→BaCO₃(s)

Use the following reactions and the given values of ΔH for them:

Ba(s)+CO₂(g)+1/2 O₂(g)→BaCO₃(s), ΔH= −826.5kJ

2Ba(s)+O₂(g)→2BaO(s), ΔH= −1184.0kJ

Express your answer to four significant figures in kilojoules.

Answer 1

To calculate ΔHrxn for the reaction BaO(s)+CO₂(g)→BaCO₃(s), we can use Hess's law. By writing two equations with known enthalpy changes and adding them together,

Step-by-step explanation:

To calculate ΔHrxn for the reaction BaO(s)+CO₂(g)→BaCO₃(s), we can use the information provided in the question and apply Hess's law. We need to write two equations that can be added together to give the desired equation and for which the enthalpy changes are known.

One possible set of equations is 2Ba(s)+O₂(g)→2BaO(s) (ΔH=-1184.0 kJ/mol) and BaCO₃(s)→Ba(s)+CO₂(g)+1/2 O₂(g) (ΔH=-826.5 kJ/mol). we can cancel out certain species and calculate the ΔHrxn for the desired reaction.

By adding these two equations together, we can cancel out the Ba(s) and O₂(g) to obtain the desired equation. The ΔHrxn for the reaction BaO(s)+CO₂(g)→BaCO₃(s) is the sum of the ΔH values for the two equations, which is -1184.0 kJ/mol + (-826.5 kJ/mol)=-2010.5 kJ/mol.