Factors Influencing Reaction Rates in Chemistry

The video tutorial explains several factors that affect the rate of chemical reactions, including concentration, surface area, temperature, and catalysts. Increasing the concentration of reactants or the surface area of solids can speed up reactions. Higher temperatures lead to faster molecular movement, increasing collision frequency and force, thus accelerating reactions. Catalysts enhance reaction rates by altering collision dynamics without being consumed.

Which factor is mentioned first as affecting the rate of a chemical reaction?

• Temperature

• Concentration of a reactant

• Surface area

• Presence of a catalyst

What happens to the rate of reaction when the concentration of hydrochloric acid is increased from 3 molar to 6 molar?

• The rate of reaction remains the same

• The rate of reaction decreases

• The rate of reaction increases

• The reaction stops completely

Why does increasing the concentration of hydrochloric acid increase the rate of reaction with zinc?

• Because it reduces the surface area of zinc

• Because it increases the number of acid particles available to collide with zinc

• Because it decreases the number of collisions

• Because it changes the temperature of the solution

How does breaking a piece of zinc into smaller pieces affect the reaction rate with hydrochloric acid?

• It decreases the reaction rate

• It stops the reaction

• It increases the reaction rate

• It has no effect on the reaction rate

What is the effect of increasing the surface area of a solid reactant on the rate of reaction?

• It stops the reaction

• It decreases the rate of reaction

• It has no effect on the rate of reaction

• It increases the rate of reaction

What happens to the glow of a glow stick when the temperature is increased?

• The glow remains the same

• The glow becomes weaker

• The glow disappears

• The glow becomes stronger

Why does increasing the temperature generally increase the rate of a chemical reaction?

• Because it reduces the surface area of reactants

• Because it decreases the concentration of reactants

• Because molecules move faster and collide more frequently with greater force

• Because molecules move slower and collide less frequently

What role does a catalyst play in a chemical reaction?

• It stops the reaction

• It decreases the rate of reaction

• It has no effect on the rate of reaction

• It increases the rate of reaction without being used up

In the decomposition of hydrogen peroxide, what is used as a catalyst?

• Hydrochloric acid

• Water

• Potassium iodide

• Zinc

How does a catalyst increase the rate of a reaction?

• By affecting the kinds of collisions between particles

• By being consumed in the reaction

• By decreasing the temperature

• By reducing the concentration of reactants