TEST YOURSELF (SK025) - REACTION KINETICS AND THERMOCHEMISTRY

For the reaction 2 NO (g) + 2 H₂ (g) → N₂ (g) + 2 H₂O (g) , the rate law is rate = k [NO]² [H₂]. Which statement is INCORRECT?

• The reaction is second order with respect to NO
• The reaction is first order with respect to H₂
• The reaction is second order with respect to H₂
• The reaction is third order overall

Which of the following statements is TRUE about a catalyst?

• Catalyst increases the amount of products.
• Catalyst decreases the enthalpy of reaction.
• Catalyst does not take part chemically during the reaction.
• Catalyst changes the mechanism of reaction.

A reaction is second order with respect to Y. If the concentration of Y is doubled, how does it affect the rate of reaction?

• Remains constant
• Increase by a factor of 4
• Increase by a factor of 9
• Increase by a factor of 2

Given the activation energy of the following reaction is 99 kJ. 2 NOCl(g) ⟶ 2 NO(g) + Cl₂ (g) Choose the CORRECT statement regarding the reaction.

• The enthalpy of formation of NOCl is +49.5 kJ mol-1
• The activation energy for the reverse reaction is -99 kJ
• In the presence of catalyst, the activation energy will be more than 99 kJ
• In the presence of catalyst, the activation energy will be less than 99 kJ

Uranium-238 will decay half from its initial concentration in 4.5 billion years. This statement is an example of application of which concept?

• Activation energy
• Kinetic energy
• Rate constant
• Half life

Which of the following enthalpy change is associated to the following equation? ½ Cl₂(l) → Cl (g)

• Enthalpy of formation
• Enthalpy of atomisation
• Enthalpy of hydration
• Enthalpy of sublimation

Choose the equation that represents the enthalpy of formation of carbon dioxide, CO₂.

• C(g) + O₂(g) → CO₂(g)
• CO(s) + 1/2O₂(g) → CO₂(g)
• CO(g) + O(g) → CO₂(g)
• C(s) + O₂(g) → CO₂(g)

Consider the following thermochemical equation

• –x
• –2x
• +2x
• +x/2

The specific heat capacity of aluminium is 0.9 J g⁻¹ °C⁻¹. To raise the temperature of 10.0 g of aluminium from by 1.0°C, how much energy is needed?

• 0.09 J
• 0.90 J
• 9.0 J
• 90.0 J

Lattice energy is

• the heat released when 1 mole of ionic solid is formed from its elements.
• the heat released when 1 mole of ionic solid dissolves completely in water.
• the heat released when 1 mole of ionic solid is formed from its gaseous ions.
• the heat released when 1 mole of ionic solid is converted into its gaseous atoms