Which term describes chemical reactions that absorb energy from their surroundings?

• A. Endothermic
• B. Exothermic
• C. Spontaneous
• D. Isothermal

Answer: (A)

Verified step by step guidance

1. Understand the meaning of energy flow in chemical reactions: reactions can either release energy to the surroundings or absorb energy from them.
2. Recall that reactions releasing energy (usually as heat) to the surroundings are called exothermic reactions.
3. Recognize that reactions absorbing energy from the surroundings require an input of energy to proceed; these are called endothermic reactions.
4. Note that spontaneous reactions refer to those that occur naturally without continuous input of energy, which is different from energy absorption or release.
5. Isothermal refers to processes occurring at constant temperature, not specifically related to energy absorption or release in reactions.