Calcium carbide can be made by heating calcium oxide with carbon. How many kj of heat are absorbed in the reaction?

179Kj/mol

Explanation:

The equation for the reaction is:

CaO + 3C ⇒ CaC₂ + CO ₂

The formula for calculating the heat absorbed is:

∆Hf (Products) - ∆Hf (Reactants)

Using the heat of formation (∆Hf) for each component in the reaction

∆Hf Cao = - 635kj/mol

∆Hf C = 0kj/mol

∆Hf CaC2 = - 63kj/mol

∆Hf CO2 = - 393.5

The heat absorbed = (-63 + - 393.5) - (-635)

= - 456 + 635

= 179kj/mol