Question

explain three factors that can affect reaction rate in a chemical reaction (3 pts)
(3 points)

Explanation:

1. Concentration (or Pressure for Gases): Increasing the concentration of reactants (or pressure of gaseous reactants) increases the number of reactant particles per unit volume. This leads to more frequent collisions between reactant molecules, thus increasing the reaction rate. For example, in the reaction $\ce{2H_{2} + O_{2} -> 2H_{2}O}$, increasing the concentration of $\ce{H_{2}}$ or $\ce{O_{2}}$ will speed up the formation of water.
2. Temperature: Raising the temperature gives reactant molecules more kinetic energy. As a result, molecules move faster, collide more frequently, and a larger proportion of collisions have energy greater than or equal to the activation energy (the minimum energy required for a reaction to occur). For instance, reactions like the rusting of iron happen faster at higher temperatures.
3. Catalyst: A catalyst is a substance that increases the reaction rate without being consumed in the reaction. It works by providing an alternative reaction pathway with a lower activation energy. Enzymes in biological systems (like catalase breaking down hydrogen peroxide) are examples of catalysts that speed up reactions significantly.

Answer:

Three factors affecting chemical reaction rate are:

1. Concentration (or Pressure for Gases): More reactant particles per volume → more frequent collisions → faster reaction.
2. Temperature: Higher temperature → more kinetic energy, faster movement, more frequent and energetic collisions → faster reaction.
3. Catalyst: Provides a lower - activation - energy pathway → increases reaction rate without being consumed.