Catalyst

According to adsorption theory of catalysis, the speed of the reaction increases because:

• in the process of adsorption, the activation energy of the molecules becomes large.

• adsorption produces heat which increases the speed of the reaction

• the concentration of the reactant molecules at the active centres of the catalyst becomes high due to adsorption.

• adsorption lowers the activation energy of the reaction

Tags

NGSS.HS-PS1-4

A catalyst

• is used up

• is nevr used up

A catalyst be regenerated or used again and again

• False

• True

The following graph shows two different reaction pathways for the same overall reaction at the same temperature. Which pathway is slower and why?

• Red, because the activation energy is larger

• Blue, because the activation energy is lower

• both reaction progress at the same rate

Tags

NGSS.HS-PS1-4

Which one of the following is not an example for heterogenous catalysis?

• Hydrogenation of oil

• Manufacture of ammonia by Haber's process

• Manufacture of sulphuric acid by Contact process

• Hydrolysis of sucrose in presence of dilute hydrochloric acid

Which of these are the best choice of catalysts?

• Expensive and reusable

• Cheap and insensitive to impurities

• Cheap and easily poisoned

• Cheap and reusable

In homogeneous catalysis, reactants and catalysts are in the ___________ phase with each other.

• Different

• Same

In heterogeneous catalysis, reactants and catalysts are in a __________ phase with each other

• Different

• Same

Which of these are the BEST way to dispose waste catalyst? There are 2 correct answers.

• Landfill

• Reuse the waste catalysts

• Regenerate the waste catalysts

• Leaching by water

Tags

NGSS.HS-ETS1-3

NGSS.HS-LS2-7

What is the primary role of a catalyst in a chemical reaction?

• To increase the temperature of the reaction

• To decrease the activation energy of the reaction

• To increase the concentration of reactants

• To change the equilibrium position of the reaction