Kinetics - exam practice

These questions concern the Maxwell-Boltzmann energy distribution shown below.

What is the best way to describe the activation energy, E_a, of a reaction?

How does the addition of a catalyst to a reaction affect the shape of the Maxwell-Boltzmann distribution curve?

The reaction pathway diagram below illustrates the energies of the reactants, the products and the transition state of a reaction.

Which expression represents the activation energy of the forward reaction?

In the diagram, curve X was obtained by observing the decomposition of 100 cm³ of 1.0 mol dm^-3 hydrogen peroxide, catalysed by manganese(IV) oxide.

Which alteration to the original experimental conditions would produce curve Y?

The diagram shows the Boltzmann distribution of energies in a gas. The gas can take part in a reaction with an activation energy, E_a. The gas is maintained at a constant temperature.

Which statement is correct?

Iodine and propanone react according to the following equation.

I_2(aq) + CH₃COCH_3(aq) ➔ CH₃COCH₂I_(aq) + HI_(aq)

If the concentration of propanone is increased, keeping the total reaction volume constant, the rate of the reaction also increases.

What could be the reason for this?

A Maxwell-Boltzmann curve shows the distribution of molecular energies in a reaction system.

When the temperature in this system is increased, the peak is

What is the main reason for the increase in reaction rate with increasing temperature?

The figure shows a typical energy distribution for particles of an ideal gas in a sealed container at a fixed temperature.

Which of the following statements is true?

The Maxwell-Boltzmann distribution of molecular energies in a sample of gas at a fixed temperature is shown.

Which letter represents the mean energy of the molecules?