Question

Which of the following represent an decrease in potential energy? (Select all that apply.)
An electon absorbs a photon.
A liquid freezes.
A solid sublimes.
A chemical bond forms.
A vapor condenses.
Positive and negative ions separate.

Answer 1

Okay I have two things: One, I think you would have better luck asking this in the Physics section. And Two, luckily I am good in science and will try to help you.

Do you know what potential energy is?

Answer 2

i know what it is but not in depth

Answer 3

and can you help me with some other problems too after this? I would greatly appreciate it!

Answer 4

Okay, ask yourself: does energy need to go in or come out for the process (of potential energy) to occur? Is it likely to happen on its own?

That photon is energy that the system absorbs, so potential energy increases.

Condensation and freezing both happen when the substance is cooled, which means energy is taken out of the system. potential energy decreases.

A solid needs to be heated to sublime, because you're taking virtually stationary molecules in the solid and making them start flying around the room as a gas. potential energy increases.\

LOOK --> A chemical bond forming releases energy and is spontaneous, so potential energy decreases.

Those particles want to stick together...you'll have to do work on them to get them apart. potential energy increases.

Answer 5

And: I think I could help you.

Answer 6

thanks hold on one second

Answer 7

How much heat energy is needed to raise the temperature of a 28 g sample of aluminum from 22.4°C to 87.1°C? Refer to Table 17-1 for the specific heat of aluminum.

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