Reaction Rates Exit Ticket

Which of the following factors does NOT affect the rate of a chemical reaction?

• Temperature

• Color of reactants

• Concentration of reactants

• Presence of a catalyst

Tags

NGSS.HS-PS1-5

Which statement best describes the role of a catalyst in a chemical reaction?

• It increases the activation energy required.

• It is consumed during the reaction.

• It speeds up the reaction without being used up.

• It changes the products of the reaction.

According to collision theory, what must happen for a chemical reaction to occur between two particles?

• They must collide with sufficient energy and proper orientation.

• They must be in the same physical state.

• They must have the same mass.

• They must be heated to boiling point.

If the concentration of a reactant in a solution is doubled, what generally happens to the rate of the reaction?

• It decreases

• It stays the same

• It increases

• It stops completely

Tags

NGSS.HS-PS1-5

• Higher temperature increases the frequency and energy of collisions.

• Lower temperature increases the activation energy.

• Temperature has no effect on reaction rate.

• Higher temperature decreases the number of collisions.

Tags

NGSS.HS-PS1-5

Which of the following best explains why powdered solids react faster than solid blocks of the same substance?

• Powdered solids have a greater surface area for collisions.

• Powdered solids have a lower activation energy.

• Powdered solids are heavier.

• Powdered solids are more colorful.

A reaction between substances A and B is very slow at room temperature. Suggest a way to increase the rate of this reaction and explain why it would work.

• Increase the temperature, because particles will move faster and collide more often with enough energy.

• Decrease the concentration of A, because it will make the reaction faster.

• Remove any catalyst present, because it will speed up the reaction.

• Lower the temperature, because it increases the activation energy.

Tags

NGSS.HS-PS1-5

A student is investigating the effect of concentration on the rate of a reaction. She mixes different concentrations of hydrochloric acid with magnesium ribbon and measures the time taken for the reaction to finish. What evidence should she look for to conclude that concentration affects reaction rate?

• The reaction finishes faster with higher acid concentrations, indicating increased reaction rate.

• The color of the solution changes with concentration.

• The mass of magnesium ribbon increases with higher concentration.

• The temperature of the solution decreases with higher concentration.

Tags

NGSS.HS-PS1-5