Which term describes a reaction that releases heat?

Which term describes a reaction that releases heat?

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

Answer: (A)

When a reaction releases heat, it is exothermic. This means energy is given off to the surroundings, often making the surrounding environment feel warmer. The enthalpy change for such reactions is negative, reflecting the loss of energy from the system. In contrast, endothermic reactions absorb heat from the surroundings, so they tend to feel cooler. Isothermal processes stay at a constant temperature, regardless of heat flow, and adiabatic processes involve no heat exchange with the surroundings, so any temperature change comes from internal work or energy changes. So describing a reaction that releases heat points to the exothermic term.

When a reaction releases heat, it is exothermic. This means energy is given off to the surroundings, often making the surrounding environment feel warmer. The enthalpy change for such reactions is negative, reflecting the loss of energy from the system. In contrast, endothermic reactions absorb heat from the surroundings, so they tend to feel cooler. Isothermal processes stay at a constant temperature, regardless of heat flow, and adiabatic processes involve no heat exchange with the surroundings, so any temperature change comes from internal work or energy changes. So describing a reaction that releases heat points to the exothermic term.