Titanium occurs naturally as the mineral rutile, TiO2. One possible method of extraction of titanium is to reduce the rutile by heating with carbon. TiO2(s) + 2C(s) Ti(s) + 2CO(g) → The standard enthalpy changes of formation of TiO2(s) and CO(g) are –940 kJ mol–1 and –110kJ mol–1 respectively. What is the standard enthalpy change of this reaction?

The standard entalpy change for the reaction is 720 kJ/mol

Explanation:

The chemical equation for the reaction is given as follows;

TiO₂ (s) + 2C → Ti (s)  + 2CO

The standard enthalpy changes of formation for TiO₂ (s) = -940 kJ/mol

The standard enthalpy changes of formation for CO (g) = -110 kJ/mol

The enthalpy change of the reaction = The enthalpy of the products - The enthalpy of the reactants

Given that there are two moles of CO, we have;

The enthalpy of the products= -110 × 2 = -220 kJ/mol

∴ The enthalpy change = -220 - (-940) = 720 kJ/mol

The standard entalpy change for the reaction = 720 kJ/mol.