C3.2.1 Exothermic and Endothermic Reactions

• What happens to the temperature of the surroundings in an exothermic reaction?

  Increases
• The combustion of fuels is an example of a(n) exothermic
• What happens to the temperature of the surroundings in an endothermic reaction?

  Decreases
• Photosynthesis is an example of a(n) endothermic
• What is the enthalpy change (ΔH) for exothermic reactions?

  Negative
• What does a positive enthalpy change (ΔH) indicate?

  Endothermic reaction
• The decomposition of hydrogen peroxide is an exothermic reaction.

  False
• What happens to the temperature during an exothermic reaction?

  Increases
• What is the sign of ΔH for exothermic reactions?

  Negative
• Endothermic reactions absorb heat from the surroundings.


  True
• Exothermic reactions are characterized by a negative change in enthalpy
• The temperature decreases during endothermic reactions.


  True
• What is the enthalpy change for endothermic reactions?

  Positive
• Endothermic reactions lead to a positive change in enthalpy
• What is an example of an exothermic reaction?

  Neutralization reaction
• The change in enthalpy (ΔH) for endothermic reactions is always positive.

  True
• The temperature increases in exothermic reactions.


  True
• What do endothermic reactions absorb from the surroundings?

  Heat
• In endothermic reactions, the change in enthalpy (ΔH) is positive
• Exothermic reactions have a higher activation energy than endothermic reactions.

  False
• What happens to the temperature in endothermic reactions?

  Decreases
• In exothermic reactions, the temperature of the surroundings increases
• Photosynthesis is an endothermic reaction.


  True
• The enthalpy change (ΔH) for exothermic reactions is positive.

  False
• Match the heat exchange with the type of reaction:

  Releases heat ↔️ Exothermic

  Absorbs heat ↔️ Endothermic
• The enthalpy change (ΔH) for endothermic reactions is negative.

  False
• Arrange the following characteristics to compare exothermic and endothermic reactions:

  1️⃣ Heat Exchange

  2️⃣ Temperature

  3️⃣ Enthalpy Change (ΔH)
• Endothermic reactions absorb heat from the surroundings
• Match the reaction type with its effect on temperature:

  Exothermic ↔️ Increases temperature

  Endothermic ↔️ Decreases temperature
• Exothermic reactions have a negative enthalpy change (ΔH).
• The change in enthalpy (ΔH) for endothermic reactions is negative.

  False
• Match the reaction type with its enthalpy change:

  Exothermic ↔️ Negative

  Endothermic ↔️ Positive
• What is an example of an exothermic reaction?

  Combustion of fuels
• Photosynthesis is an example of an endothermic
• Exothermic reactions result in a negative ΔH.


  True
• Steps to identify exothermic or endothermic reactions

  1️⃣ Check if heat is released or absorbed

  2️⃣ Observe temperature change

  3️⃣ Determine the sign of ΔH
• Endothermic reactions absorb heat from the surroundings
• What type of reactions release heat into the surroundings?

  Exothermic reactions
• In exothermic reactions, the change in enthalpy (ΔH) is negative
• The temperature decreases in endothermic reactions.


  True