Factors Affecting the Rates of Chemical Reactions

What is the suggestion of Svante Arrhenius in 1888 about chemical reaction?

• Activated complex is located at the peak of the energy diagram for a

  reaction.

• Catalyst may be recovered unchanged at the end of the process.

• Particles must possess a certain minimum amount of kinetic energy in

  order to react.

• Smaller pieces have a greater surface area, thus, providing much greater

  contact among the reactants and effecting more collisions.

Which of the following statements best describes Collision Theory?

• Atoms or molecules must collide with sufficient amount of energy in order

  to react.

• Catalyst can be recovered unchanged at the end of the process

• Increasing the concentration of a reactant increases the rate of reaction.

• Smaller pieces have a greater surface area, thus, providing much greater

  contact among the reactants and effecting more collisions.

How will you increase the rate of a chemical reaction?

• add catalyst

• decrease the concentration of reactants

• decrease the temperature of reactants

• increase the surface area of reactants

The amount of energy required to break the bonds between the reacting molecules is known as _______.

• Activated Complex

• Activation Energy

• Collision Theory

• Law of Conservation of Mass

One of the factors that affect the rate of chemical reaction is concentration of

solution. Describe this factor.

• It is the measure of the number of particles of solute in a given volume of

  solution.

• It is located at the peak of the energy diagram for a reaction.

• It is the amount of energy needed for molecules to react.

• It is needed to break the bonds of the reactants to form new products or

  new substances.

What refers to the peak of the energy diagram for a chemical reaction?

• Activated Complex

• Activation Energy

• Collision Theory

• Law of Conservation of Mass

How will crushing a solid into a powder increase reaction rate?

• The activation energy barrier will be lowered.

• The orientation of colliding particles will be improved.

• The particles will collide with more energy.

• The powdered form has more surface area.

The rate of reaction increases as the temperature increases. Which of the

following statements provides the best explanation for this?

• At higher temperature, the particles have more energy, move faster and

  collide more often.

• At lower temperature, the particles do not collide with each other.

• Higher temperature has higher activation energy.

• Increasing the temperature increases the number of particles, so they

  collide more often.

When a lit match touches the wick of a candle, it begins to burn. When the

match is removed, the candle continues to burn. The match ____________.

• behaves as a catalyst

• increases the concentration

• lowers the activation energy barrier

• supplies the activation energy

Manganese (IV) dioxide acts as a catalyst in the decomposition of hydrogen

peroxide. How does a catalyst increase the rate of reaction?

• increasing the concentration of reactant(s)

• decreasing the concentration of reactant(s)

• increasing the activation energy of the overall reaction

• decreasing the activation energy of the overall reaction