The speed, or rate, of a chemical reaction is influenced by
(a) The presence of catalysts
(b) The temperature
(c) The concentration of the reactants
(d) a, b, and c are all correct

Verified step by step guidance

1. Understand that the speed or rate of a chemical reaction depends on factors that affect how quickly reactant molecules interact and convert into products.
2. Recognize that catalysts increase the reaction rate by lowering the activation energy needed for the reaction, allowing it to proceed faster without being consumed.
3. Know that temperature influences reaction rate because higher temperatures increase the kinetic energy of molecules, leading to more frequent and energetic collisions.
4. Acknowledge that the concentration of reactants affects the reaction rate since higher concentrations mean more reactant molecules are available to collide and react.
5. Combine these concepts to conclude that all the factors listed (presence of catalysts, temperature, and concentration of reactants) influence the speed of a chemical reaction.

Key Concepts

Catalysts and Their Role in Reaction Rate

Catalysts are substances that increase the speed of a chemical reaction without being consumed. They work by lowering the activation energy needed for the reaction, allowing more reactant molecules to convert into products faster.

Effect of Temperature on Reaction Rate

Increasing temperature generally increases the reaction rate because it raises the kinetic energy of molecules. This leads to more frequent and energetic collisions, making it easier for reactants to overcome the activation energy barrier.

Concentration of Reactants and Reaction Rate

Higher concentration of reactants increases the likelihood of collisions between molecules. More collisions per unit time typically result in a faster reaction rate, as there are more opportunities for reactants to interact and form products.