Understanding Reaction Profiles: Exothermic, Endothermic, and Activation Energy

The video tutorial explains reaction profiles, focusing on exothermic and endothermic reactions, and the concept of activation energy. Exothermic reactions release energy to the surroundings, while endothermic reactions absorb energy. Activation energy is the minimum energy required for a reaction to occur. The tutorial uses examples like combustion and cooling packs to illustrate these concepts.

What happens to the energy of reactants in an exothermic reaction?

• Energy remains constant.

• Energy is released to the surroundings.

• Energy is converted into mass.

• Energy is absorbed from the surroundings.

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

• Evaporation

• Photosynthesis

• Burning fuel

• Melting ice

In an endothermic reaction, what happens to the energy of the surroundings?

• It is converted into light.

• It increases.

• It decreases.

• It remains unchanged.

Which of the following is a characteristic of endothermic reactions?

• They release energy to the surroundings.

• They absorb energy from the surroundings.

• They convert energy into mass.

• They do not involve energy changes.

What is activation energy?

• The minimum energy required for a reaction to occur.

• The energy absorbed during a reaction.

• The energy that remains constant during a reaction.

• The energy released during a reaction.

How do molecules react according to the concept of activation energy?

• By absorbing energy from the surroundings.

• By remaining stationary.

• By colliding with enough energy.

• By releasing energy to the surroundings.

What happens if molecules do not have enough energy during a collision?

• They react immediately.

• They bounce off each other.

• They form a new compound.

• They release energy.