Question

question select all the correct answers. some chemical reactions absorb energy rather than release it. which of these phenomena are caused by chemical reactions that absorb energy? if youre not sure, make a guess. plants use sunlight and atmospheric gases to make food. a person activates a cold pack by hitting it against a surface. a rechargeable battery is plugged in to charge. heat is used to separate a compound into its elements.

Explanation:

• Photosynthesis in plants uses sunlight (energy - input) to convert atmospheric gases into food, an endothermic chemical reaction.
• In a cold - pack, an endothermic chemical reaction occurs when activated, absorbing heat from the surroundings.
• Charging a rechargeable battery involves an endothermic electrochemical reaction where electrical energy is absorbed to convert substances back to their original state.
• Separating a compound into its elements using heat is an endothermic process as heat energy is absorbed to break the chemical bonds.

Answer:

Plants use sunlight and atmospheric gases to make food.
A person activates a cold pack by hitting it against a surface.
A rechargeable battery is plugged in to charge.
Heat is used to separate a compound into its elements.