Rates of reaction and energy changes: Practice Questions

When sodium thiosulfate reacts with hydrochloric acid, the solution becomes cloudy. Which statement correctly explains the effect of increasing the temperature on the rate of this reaction?

Calculate the overall energy change for the reaction:
\( \text{H}_2 + \text{Cl}_2 \rightarrow 2\text{HCl} \)

Given the bond energies:
H-H: 436 kJ/mol
Cl-Cl: 243 kJ/mol
H-Cl: 432 kJ/mol

A student investigates the rate of reaction between marble chips and dilute hydrochloric acid.
Describe one practical method the student could use to determine the rate of this reaction by measuring the production of a gas.

Calculate the overall energy change for the reaction: \(H_{2} + Cl_{2} \rightarrow 2HCl\).
Use the following bond energies:
\(H-H = 436\text{ kJ mol}^{-1}\)
\(Cl-Cl = 243\text{ kJ mol}^{-1}\)
\(H-Cl = 432\text{ kJ mol}^{-1}\)

Explain how the addition of a catalyst increases the rate of a chemical reaction in terms of activation energy and reaction profiles.

a) State two factors that can increase the rate of a chemical reaction.
b) Explain, using collision theory, why increasing the temperature of a reaction increases the rate of reaction.
c) In a reaction, the total energy required to break the bonds in the reactants is \(2500\text{ kJ mol}^{-1}\). The total energy released when new bonds are formed in the products is \(2850\text{ kJ mol}^{-1}\). Calculate the overall energy change and state whether the reaction is endothermic or exothermic.