Which of the following is an endothermic process?
Group of answer choices
a. heat energy flows from the system to the surroundings
b. none of the above
c. work is done on the system by the surroundings
d. heat energy is evolved by the system e work is done by the system on the surroundings
The correct answer and explanation is:
The correct answer is c. work is done on the system by the surroundings.
Explanation: An endothermic process is one where the system absorbs energy, usually in the form of heat, from its surroundings. When work is done on the system by the surroundings, energy is transferred into the system. This energy input increases the internal energy of the system, making it an endothermic process.
In contrast to exothermic processes, where energy flows out of the system, endothermic processes involve the absorption of heat. A good example is the melting of ice, where heat is absorbed from the surroundings to change the state of the ice from solid to liquid.
Breaking down the other options:
- a. heat energy flows from the system to the surroundings: This is an exothermic process because heat is leaving the system.
- b. none of the above: This is not correct because option c is a valid endothermic process.
- d. heat energy is evolved by the system: When heat is evolved by the system, it’s releasing energy, indicating an exothermic process.
- e. work is done by the system on the surroundings: This would result in energy being transferred out of the system, which is characteristic of an exothermic process.
Thus, when work is done on the system by the surroundings, the system absorbs energy, making the process endothermic.