Chemistry Chapter: Exothermic and Endothermic Reactions

Exothermic Reactions

• Exothermic reactions release heat energy, increasing the temperature of the surroundings
• Examples include combustion reactions, such as burning fuel, which release energy and heat up the surroundings
• The heat energy released can be used to cook food, warm up people, and increase the kinetic energy of air particles in the surroundings

Endothermic Reactions

• Endothermic reactions take in heat energy, decreasing the temperature of the surroundings
• Examples include treating sports injuries, where an endothermic reaction can be used to cool down the injured area and reduce pain
• Endothermic reactions are useful for cooling down injuries, promoting healing, and reducing pain

Determining Reaction Type

• To determine if a reaction is endothermic or exothermic, measure the temperature change of the surroundings
• Use a polystyrene cup, which is a good insulator, to minimize heat conduction
• Measure the starting temperature, add reactants, and monitor the temperature change
• If the temperature increases, the reaction is exothermic; if it decreases, the reaction is endothermic

Experimental Procedure

• Add one reactant to a polystyrene cup and measure the starting temperature
• Add the second reactant and stir to initiate the chemical reaction
• Monitor the temperature change to determine if the reaction is endothermic or exothermic

Exothermic Reactions

• Release heat energy, increasing the temperature of the surroundings
• Examples include combustion reactions, such as burning fuel
• Heat energy released can be used to cook food, warm up people, and increase kinetic energy of air particles

Endothermic Reactions

• Take in heat energy, decreasing the temperature of the surroundings
• Examples include treating sports injuries to cool down the injured area and reduce pain
• Useful for cooling down injuries, promoting healing, and reducing pain

Determining Reaction Type

• Measure temperature change of the surroundings to determine if a reaction is endothermic or exothermic
• Use a polystyrene cup to minimize heat conduction
• Measure starting temperature, add reactants, and monitor temperature change
• If temperature increases, the reaction is exothermic; if it decreases, the reaction is endothermic

Experimental Procedure

• Add one reactant to a polystyrene cup and measure the starting temperature
• Add the second reactant and stir to initiate the chemical reaction
• Monitor temperature change to determine if the reaction is endothermic or exothermic

Learn about the differences between exothermic and endothermic reactions, including their effects on the surroundings and examples of each.