Basic Kinetics Review

Which one of the following is NOT a key concept of the collision theory:

• particles must collide in order to react

• particles must move slowly when they collide, otherwise they simply “bounce off” one another

• particles must collide with the proper orientation

• particles must collide with sufficient energy to reach the activated complex in order to react

Which one of the following factors does not affect the rate of a chemical reaction: (a)  

• humidity
• concentration
• temperature
• nature of the reactants

The rate of a chemical reaction normally

• increases as temperature decreases.

• decreases when a catalyst is added.

• increases as reactant concentration increases.

• decreases as reactant concentration increases.

Tags

NGSS.HS-PS1-5

Crushing a solid into a powder will increase reaction rate because:

(a)  

• the powdered form has more surface area
• the particles will collide with more energy
• the orientation of colliding particles will be improved
• the activation energy barrier will be lowered

What happens to a catalyst in a reaction?

• It remains unchanged.

• It is incorporated into the reactants.

• It is incorporated into the products.

• It evaporates.

It is generally believed that catalysts increase reaction rates by:

• removing the activation energy barrier

• providing an alternate activation energy barrier that is lower than the original barrier

• lowering the activation energy barrier

• giving the reacting particles more energy, thus there will be more successful collisions

Tags

NGSS.HS-PS1-4

Why does a higher concentration increase the rate of reaction?

• it increases the amount of reactants

• it lowers the activation energy

• it increases the energy of particle collisions

• it increases the frequency of particle collisions

Tags

NGSS.HS-PS1-5

Why does a higher temperature increase the rate of a reaction?

(a)  

• it increases both the frequency and energy of particle collisions
• it only increases the frequency of particle collisions
• it only increases the energy of particle collisions
• it reduces the activation energy of the reaction

Tags

NGSS.HS-PS1-5

The energy needed by reactants for an effective collision is called the (a)  

• activation energy
• change in entropy
• change in enthalpy
• free energy

What type of reaction is this? (a)  

• Endothermic
• Exothermic

Tags

NGSS.HS-PS1-4

NGSS.HS-PS3-4