Question

multiple select question
select all that apply
which statement(s) about exothermic and endothermic reactions is/are true?
□ in endothermic reactions, thermal energy is absorbed.
□ dissolving epsom salts in water is an example of an exothermic change because the solution becomes cold.
□ endothermic and exothermic changes can be chemical or physical.
□ baking is an example of an exothermic change because it takes place in a hot oven.
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Explanation:

• Endothermic reactions: Absorb thermal energy. So, the statement "In endothermic reactions, thermal energy is absorbed" is true.
• Exothermic reactions: Release thermal energy. Baking involves chemical reactions that release energy (exothermic), but the reason given ("because it takes place in a hot oven") is incorrect. The key is the energy change in the reaction, not the oven's temperature. Dissolving Epsom salts in water is endothermic (solution becomes cold as it absorbs heat), so the statement about it being exothermic is false.
• Thermal changes: Endothermic and exothermic changes can be chemical (like burning - exothermic, a chemical reaction) or physical (like melting ice - endothermic, a physical change). So, the statement "Endothermic and exothermic changes can be chemical or physical" is true.

Answer:

• In endothermic reactions, thermal energy is absorbed.
• Endothermic and exothermic changes can be chemical or physical.