Robin is experimenting with an unknown solid. He discovers that the substance can dissolve in water. When this substance is a solid, it has a higher potential energy than when it is dissolved.

What will happen during dissolution of this substance?

Responses

The temperature of the surroundings will first decrease, and then increase.
The temperature of the surroundings will first decrease, and then increase.

The temperature of the surroundings will first increase, and then decrease.
The temperature of the surroundings will first increase, and then decrease.

The temperature of the surroundings will decrease.
The temperature of the surroundings will decrease.

The temperature of the surroundings will increase.

1 answer

When the substance dissolves in water and has a higher potential energy as a solid than when it is dissolved, this indicates that the dissolution process is exothermic. That means energy is released when the solid dissolves in water, leading to an increase in the energy of the surrounding system (the water).

However, if the process initially involves breaking bonds in the solid, there may be an initial absorption of energy which could temporarily decrease the temperature of the surroundings. But since the potential energy of the substance decreases overall as it dissolves (indicating that more energy is released than absorbed during the process), the final effect will lead to an overall increase in temperature.

Thus, the best interpretation of this situation is that the temperature of the surroundings will first decrease (due to the initial energy required to break apart the solid) and then eventually increase (due to the energy released during the dissolution).

So, the correct response would be: The temperature of the surroundings will first decrease, and then increase.