Which process describes heat being absorbed from the surroundings?

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

Answer: (B)

Heat flowing into a system from its surroundings is an endothermic process. Endothermic means the system gains energy by heat transfer (q > 0), so absorbing heat from the surroundings fits this description directly. In contrast, exothermic processes release heat to the surroundings (q < 0). Adiabatic processes involve no heat exchange with the surroundings (q = 0), so heat cannot be absorbed in that case. Isothermal describes a constant temperature, and while heat transfer can occur during such a process, the defining feature is the fixed temperature, not the direction of heat flow.