Question

a cold pack is broken, allowing two chemical substances to mix, making the pack cold. which statement accurately describes the flow of energy in this reaction? (1 point)
the system gains energy from the surroundings.
both of the substances are present at the end of the reaction, each with more energy than before the reaction.
energy flows from one of the substances to the other with no change in energy of the system.
the surroundings gain energy from the system.

Explanation:

In a cold pack reaction (an endothermic process), the system (the chemicals in the pack) absorbs energy from the surroundings (like the environment or your skin). The second option is wrong because substances in endothermic reactions don't gain energy on their own in that way. The third is wrong as energy isn't just transferring between substances without system - surrounding interaction. The fourth is wrong because in an endothermic reaction, the system takes energy from the surroundings, not the other way around. So the correct statement is that the system gains energy from the surroundings.

Answer:

The system gains energy from the surroundings.