Endo and Exothermic Reactions

What is the definition of an endothermic reaction?

• A reaction that does not involve any heat exchange

• A reaction that occurs at a constant temperature

• A reaction that releases heat to its surroundings

• A reaction that absorbs heat from its surroundings.

Tags

NGSS.HS-PS1-4

What is the definition of an exothermic reaction?

• A chemical reaction that releases energy in the form of heat or light.

• A chemical reaction that absorbs energy in the form of heat or light.

• A process where energy is neither released nor absorbed.

• A reaction that occurs at a constant temperature.

Tags

NGSS.HS-PS1-4

Can you provide an example of an endothermic reaction?

• Methane + Oxygen -> Carbon dioxide + Water (exothermic)

• Ammonium nitrate + Water -> Ammonium nitrate solution (endothermic)

• Iron + Oxygen -> Iron oxide (exothermic)

• Hydrochloric acid + Sodium hydroxide -> Sodium chloride + Water (exothermic)

Can you provide an example of an exothermic reaction?

• Freezing of water

• Combustion of gasoline

• Boiling water

• Photosynthesis in plants

Tags

NGSS.HS-PS1-4

In endothermic reactions, does the system gain or lose energy?

• maintain

• lose

• release

• gain

Tags

NGSS.HS-PS1-4

In exothermic reactions, does the system gain or lose energy?

• absorb energy

• lose energy

• gain energy

• stay the same

Tags

NGSS.HS-PS1-4

What happens to the surroundings in an endothermic reaction?

• The surroundings remain unchanged.

• The surroundings heat up.

• The surroundings cool down.

• The surroundings disappear.

Tags

NGSS.HS-PS3-4

What happens to the surroundings in an exothermic reaction?

• The surroundings remain unchanged.

• The surroundings turn purple.

• The surroundings warm up.

• The surroundings cool down.

Tags

NGSS.HS-PS1-4

NGSS.HS-PS3-4

How are energy changes represented in endothermic reactions?

• Negative values

• Zero values

• Positive values

• Fractional values

Tags

NGSS.HS-PS1-4

How are energy changes represented in exothermic reactions?

• By absorbing heat

• By a release of heat

• By remaining constant

• By emitting light

Tags

NGSS.HS-PS1-4