Understanding Energy Changes in Chemical Reactions

The video tutorial explains chemical reactions, focusing on energy changes. It distinguishes between exothermic reactions, which release energy, often as heat, and endothermic reactions, which absorb energy. Examples include baking cookies and bonfires for exothermic reactions, and photosynthesis for endothermic reactions. The tutorial concludes with a review and quiz questions to reinforce learning.

What is a characteristic of exothermic reactions?

• They always produce light.

• They do not involve energy changes.

• They release energy to their surroundings.

• They absorb energy from their surroundings.

Which of the following is an example of an exothermic reaction?

• Melting ice

• Baking cookies

• Evaporation of water

• Photosynthesis

What happens when a glow stick is activated?

• It absorbs heat from the surroundings.

• It releases light energy.

• It changes color without any energy change.

• It absorbs light energy.

Endothermic reactions typically require what to proceed?

• A constant input of energy

• A decrease in temperature

• No energy change

• A release of light

Photosynthesis is an example of which type of reaction?

• Endothermic

• Exothermic

• Spontaneous

• Neutral