C310 - Catalysts

Why are platinum, palladium, and rhodium used in catalytic converters?

• They are the cheapest metals.
• They are effective at converting exhaust gases.
• They are colorful.
• They add weight to the vehicle.

What is a characteristic feature of all catalysts?

• They change color when the reaction occurs.
• They emit light during the reaction.
• They are universal and work for any reaction.
• They are specific to certain reactions.

What happens to the rate of a chemical reaction when the concentration of a catalyst is increased?

• It remains constant.
• It decreases significantly.
• It generally increases up to a certain point.
• It first decreases, then increases.

Tags

NGSS.HS-PS1-5

Why are enzymes considered biological catalysts?

• They decrease the energy products have.
• They speed up biochemical reactions in organisms.
• They are consumed by reactions.
• They only work outside living organisms.

In the context of environmental science, why are catalysts important?

• They increase the amount of waste.
• They are used to generate pollutants.
• They help in pollution control.
• They decrease air quality.

Tags

NGSS.HS-LS2-7

What is the role of a catalyst in an endothermic reaction?

• It increases the temperature of the reactants.
• It lowers the energy barrier for the reaction.
• It supplies energy to the reaction.
• It absorbs the products.

Which statement best describes the energy profile of a catalyzed reaction?

• The activation energy is reduced.
• The total energy of the products increases.
• The energy of the reactants decreases.
• The energy of the reaction remains the same.

What is activation energy?

• The energy needed to stop a reaction.
• The energy produced by a reaction.
• The maximum energy of reactants.
• The minimum energy required to start a chemical reaction.

How do catalytic converters reduce vehicle emissions?

• By filtering out pollutants mechanically.
• By absorbing exhaust fumes.
• By converting harmful gases into less harmful ones.
• By increasing fuel efficiency.

Tags

NGSS.HS-ESS3-4

What does a catalyst do to the activation energy of a reaction?

• It has no effect on activation energy.
• It increases the activation energy.
• It lowers the activation energy.
• It measures the activation energy.