Exothermic and Endothermic Reactions

Multiple Choice

A sample of magnesium sulfate is placed in 50.0g of water at 20°C in a calorimeter. The student stirs the sample and monitors the temperature. The temperature rises to 25°C. How would you describe the dissolution of magnesium sulfate in water?

• Endothermic Reaction

• Exothermic Reaction

Multiple Choice

What is the term for the energy required to break the bonds in the reactants for a chemical reaction to occur?

• Activation Energy

• Kinetic Energy

• Potential Energy

• Thermal Energy

Multiple Choice

What is the difference between endothermic and exothermic reactions based on energy changes?

• Endothermic reactions absorb energy, while exothermic reactions release energy.

• Endothermic reactions release energy, while exothermic reactions absorb energy.

• Both types of reactions absorb energy.

• Both types of reactions release energy.

Categorize

Options (10)

Heat is absorbed

Heat is released

$$-\Delta H$$  

$$+\Delta H$$  

Temperature of the surroundings decreases

Temperature of the surroundings increases

Bonds are formed

Bonds are broken

Heat is a reactant

Heat is a product

Organize characteristics as either endothermic or exothermic

Endothermic

Exothermic

Multiple Choice

According to the potential energy diagram shown above, the chemical reaction in the forward direction is

• exothermic because it absorbs energy

• exothermic because it releases energy

• endothermic because it absorbs energy

• endothermic because it releases energy

Categorize

Options (8)

absorbs energy

releases energy

photosynthesis

burning wood

baking bread

combustion of fuel

handwarmer

melting ice

Sort the types of reactions into their correct category.

Endothermic

Exothermic

Multiple Choice

What is the significance of the activation energy in an exothermic reaction?

• It is the energy released during the reaction

• It is the energy required to break bonds

• It is the energy that determines the speed of the reaction

• It is the energy that is absorbed during the reaction

Categorize

Options (8)

fireworks going off

photosynthesis

burning wood

rusting iron

explosion of a bomb

melting ice

evaporation of water

sublimation of dry ice

Organize these options into the right categories

Exothermic

Endothermic

Poll

How confident do you feel about this topic now?

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• Somewhat confident
• Not confident