Half-Life and Reaction Rates

The video tutorial explains the decomposition of ammonia on a metal surface as a zero-order reaction. It provides the reaction equation and initial conditions, then calculates the concentration of ammonia after one hour. An error in the initial calculation is corrected, and the correct concentration is determined. Finally, the tutorial calculates the half-life of ammonia, explaining the steps involved in the process.

What type of reaction is the decomposition of ammonia on a metal surface?

• Second-order reaction

• Third-order reaction

• First-order reaction

• Zero-order reaction

What is the rate constant for the decomposition of ammonia given in the problem?

• 2.5 x 10^-3 mol/L/s

• 2.5 x 10^-4 mol/L/s

• 2.5 x 10^-5 mol/L/s

• 2.5 x 10^-6 mol/L/s

How is the rate of a zero-order reaction determined?

• It depends on the concentration of the reactant.

• It is independent of the concentration of the reactant.

• It depends on the pressure only.

• It depends on the temperature only.

What was the initial incorrect calculation for the concentration of ammonia after 1 hour?

• 1.8 molar

• 2.2 molar

• 4.0 molar

• 3.1 molar

What is the correct concentration of ammonia after 1 hour?

• 1.8 molar

• 3.1 molar

• 4.0 molar

• 2.2 molar

What is the definition of half-life in the context of this reaction?

• Time for the concentration to double

• Time for the concentration to drop by 25%

• Time for the concentration to drop by 50%

• Time for the concentration to triple

What is the initial concentration of ammonia used to calculate the half-life?

• 2 molar

• 3 molar

• 5 molar

• 4 molar

How long does it take for the concentration of ammonia to drop to half its initial value?

• 2.22 hours

• 4.44 hours

• 1.11 hours

• 3.33 hours

What is the half-life of ammonia in seconds?

• 2000 seconds

• 5000 seconds

• 3000 seconds

• 4000 seconds

How is the half-life of ammonia expressed in minutes?

• 55.55 minutes

• 66.66 minutes

• 44.44 minutes

• 33.33 minutes