Understanding Reaction Mechanisms and Molecularity

What is the purpose of discussing reaction mechanisms in chemistry?

• To explore the molecular pathway of reactions

• To understand the stoichiometry of reactions

• To determine the color of reactants

• To calculate the mass of products

What is an intermediate in a reaction mechanism?

• A product that is formed and consumed during the reaction

• A reactant that starts the reaction

• A byproduct that is not involved in the main reaction

• A catalyst that speeds up the reaction

Which type of reaction involves the decomposition of a single molecule?

• Unimolecular reaction

• Termolecular reaction

• Bimolecular reaction

• Multimolecular reaction

Why are termolecular reactions less common than bimolecular reactions?

• They involve more complex molecules

• They produce more byproducts

• They require more energy

• The probability of three molecules colliding simultaneously is low

What is the molecularity of a reaction involving two molecules colliding?

• Bimolecular

• Unimolecular

• Termolecular

• Multimolecular

Which of the following is an example of a bimolecular reaction?

• Decomposition of cyclobutane

• Reaction of nitrogen monoxide with oxygen

• Formation of water from hydrogen and oxygen

• Decomposition of ozone

What is the rate-determining step in a reaction mechanism?

• The fastest step in the reaction

• The step that limits the overall reaction rate

• The step that produces the most products

• The step that requires the least energy

How can the rate law of a reaction be determined from the reaction mechanism?

• By using the stoichiometry of the overall reaction

• By analyzing the rate-determining step

• By calculating the mass of the reactants

• By measuring the temperature of the reaction

What happens to the rate law when the rate-determining step is the first step in a reaction mechanism?

• It requires experimental data to be determined

• It is directly derived from the stoichiometry of the first step

• It matches the stoichiometry of the overall reaction

• It becomes independent of the reaction mechanism

Why is experimental data important in determining the rate law of a reaction?

• To calculate the mass of the products

• To confirm the stoichiometry of the reaction

• To verify the color change in the reaction

• To determine the exponents in the rate law