Chemical Reactions Quiz

What is a characteristic of chemical reactions according to the image?

• They only occur in scientific laboratories.

• They result in the formation of new substances with different properties.

• They do not involve changes in physical properties.

• They can only be observed under a microscope.

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

• Freezing of water

• Toasting of bread

• Cutting of paper

• Melting of ice

What does a slow reaction rate imply about the speed of a chemical reaction?

• The reaction completes in a short amount of time.

• The reaction does not complete.

• The reaction takes a long time to complete.

• The reaction speed is variable.

Which of the following is an example of a fast reaction rate?

• Sugar dissolving in water

• A match burning

• Ice melting

• Iron rusting

How can the rate of a reaction be measured?

• By the color change of the reactants

• By how quickly the product is formed

• By the temperature change only

• By how quickly the reactants are used up

What does the term "reaction rate" refer to in chemical reactions?

• The duration it takes to use up all reactants

• The speed at which a reaction occurs

• The time it takes to prepare the reactants

• The temperature at which a reaction occurs

Arrange the following reactions in order from the slowest to the fastest reaction rate:

• Digestion, Rusting, Blood clotting, Burning wood, Explosion

• Rusting, Digestion, Blood clotting, Burning wood, Explosion

• Blood clotting, Rusting, Digestion, Explosion, Burning wood

• Explosion, Burning wood, Blood clotting, Rusting, Digestion

Which of the following factors does NOT affect the rate of a chemical reaction?

• Temperature

• Concentration

• Catalysts

• Water

What is the role of catalysts in a chemical reaction?

• They increase the temperature of the reaction.

• They decrease the concentration of reactants.

• They provide an alternative pathway with lower activation energy.

• They increase the surface area of the reactants.

How does increasing the surface area of reactants affect the reaction rate?

• It decreases the reaction rate.

• It does not affect the reaction rate.

• It increases the reaction rate.

• It changes the temperature of the reaction.