Question

Given the following reaction:

2C₂H₂(g) + 5O₂(g) → 4CO₂(g) + 2H₂O(g) ∆H = -2511.6 kJ
What is the energy change when 7.76 g of C₂H₂ react with excess O₂?

Answer 1

To find the energy change when 7.76 g of C₂H₂ react with excess O₂, we need to use the given balanced chemical equation and the enthalpy change (∆H) value. This can be done using stoichiometry to calculate the moles of C₂H₂, then using the molar ratio to determine the moles of CO₂ produced, and finally using the ∆H value to calculate the energy change.

Step-by-step explanation:

To find the energy change when 7.76 g of C₂H₂ react with excess O₂, we need to use the given balanced chemical equation and the enthalpy change (∆H) value. The balanced equation is 2C₂H₂(g) + 5O₂(g) → 4CO₂(g) + 2H₂O(g). The ∆H value for this reaction is -2511.6 kJ.

We can use stoichiometry to calculate the moles of C₂H₂ in 7.76 g.

Next, we use the molar ratio from the balanced equation to determine the moles of CO₂ produced. Finally, we use the ∆H value to calculate the energy change in kJ.