IB 6.1 Collision theory and rates of reaction

Which is a correct unit for rate of reaction?

• mol dm⁻³ s⁻¹

• mol dm⁻³

• mol s⁻¹

• mol dm3 ^s−1

• I and II only

• I and III only

• II and III only

• I, II and III

• I and II only

• I and III only

• II and III only

• I, II and III

Which will considerably increase the initial rate of the reaction between hydrochloric acid and excess solid calcium carbonate?

• Doubling the size of the container

• Doubling the size of the pieces of calcium carbonate

• Doubling the concentration of the hydrochloric acid

• Doubling the amount of the calcium carbonate

• x and y are the average enthalpy of the particles at T₁ and T₂ respectively

• T₁ > T₂

• The value of Ea is higher for T₂ than for T₁

• The areas under each graph are equal

According to collision theory what must be true for a reaction to occur when two reactant particles collide ?

• The particles must both possess kinetic energy

• The collision must occur with the proper orientation

• The particles must be travelling in opposite directions

• All the chemical bonds in both particles must be broken

Which is a correct statement about a suitable catalyst for a a specified chemical reaction?

• The catalyst alters the enthalpy change of the specified reaction.

• The catalyst is not permanently changed chemically

• The catalyst must be in the same physical state as the reactants

• The catalyst lowers the activation energy of the specified reaction.

• Rate = −0.05 mol dm⁻³ s⁻¹ with reference to Q

• Rate = 0.1 mol dm⁻³ s⁻¹ with reference to S

• Rate = 0.1 mol dm⁻³ s⁻¹ with reference to Q

• Rate = 0.1 mol dm−3 s⁻¹ with reference to P

• 1

• 2

• 3

• 4

Which factors directly explain why the rate of a reaction increases when the temperature is increased?

I. More of the reacting particles will possess the necessary activation energy.

II. The frequency of the collisions increases.

III. The value of the average kinetic energy of the particles increases

• I and II only

• I and III only

• II and III only

• I, II and III