Rates of reaction

What happens to the rate of a reaction when you decrease the temperature?

• decreases

• increases

• stays the same

Which of the following changes will NOT increase the rate of a chemical reaction?

• increase temperature

• increase surface area

• increase concentration

• decrease concentration

Which of the following statements best explains how a catalyst works?

• lowers the activation energy for the reaction

• provides an alternative route with a lower activation energy

• provides an alternative route

• speeds up the reaction without being used up

What change could you make to a solid reactant to increase the rate of a reaction?

• increase the concentration

• increase the pressure

• increase the surface area

Is the following statement true or false:

Adding manganese(IV) oxide increases the rate of a reaction

• true

• false

What is the formula of hydrogen peroxide?

• H₂O₂

• 2H₂O₂

• H₂O

• HO₂

What is a catalyst?

• A very fast moggie

• A substance that increases the rate of a reaction and is used up

• A substance that increases the rate of a reaction but is not used up

• A substance that decreases the rate of a reaction and is not used up

What will you observe when calcium carbonate reacts with hydrochloric acid?

• Effervescence and it turns white

• Effervescence and the calcium carbonate gets smaller

• A lilac flame

• The grey solid disappears

What is produced during the reaction between hydrochloric acid and marble chips?

• oxygen gas and calcium chloride

• oxygen gas and calcium carbonate

• calcium chloride, carbon dioxide and water

• water, carbon dioxide and calcium carbonate

What has to happen for a chemical reaction to occur?

• particles have to collide with at least the activation energy

• particles have to collide with less than the activation energy

• particles don't have to collide with any energy

• particles don't have to collide with at least the activation energy