Catalysts and Reaction Rates

The video tutorial explores how temperature and concentration affect the rate of chemical reactions. Increasing temperature raises the average kinetic energy, allowing more particles to overcome the activation energy barrier. Higher concentration increases the likelihood of particle collisions. The role of catalysts, such as cobalt chloride, is also discussed, highlighting how they lower activation energy and alter reaction pathways without being consumed.

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

• It remains the same.

• It stops completely.

• It increases.

• It decreases.

Why does increasing temperature increase the rate of reaction?

• It reduces the volume of the container.

• It increases the average kinetic energy of particles.

• It changes the color of the reactants.

• It decreases the number of particles.

How does increasing the concentration of reactants affect the reaction rate?

• It stops the reaction.

• It decreases the reaction rate.

• It has no effect on the reaction rate.

• It increases the reaction rate.

What is the effect of increasing concentration on particle collisions?

• It increases the chance of collisions.

• It decreases the chance of collisions.

• It has no effect on collisions.

• It prevents collisions.

In the experiment with potassium hydrogen titrate, what is observed when the temperature is increased?

• The solution freezes.

• The solution turns blue.

• The reaction stops.

• Rapid formation of bubbles is observed.

What role does a catalyst play in a chemical reaction?

• It changes the color of the products.

• It increases the activation energy.

• It decreases the activation energy.

• It consumes the reactants.

What is the effect of cobalt(II) chloride on the reaction rate in the experiment?

• It slows down the reaction.

• It has no effect on the reaction.

• It makes the reaction more vigorous.

• It stops the reaction completely.

How does a catalyst increase the reaction rate without being consumed?

• By increasing the temperature.

• By changing the reaction pathway.

• By adding more reactants.

• By decreasing the concentration.

What happens to the catalyst at the end of the reaction?

• It evaporates.

• It changes color permanently.

• It remains unchanged.

• It is consumed.

What is the ultimate effect of a catalyst on activation energy?

• It increases activation energy.

• It has no effect on activation energy.

• It decreases activation energy.

• It doubles the activation energy.