What must occur in order for a matter to change states? A: Heat must be added or removed B: A chemical change must occur C: Other substances must be added D: The temperature must change

Hey!

Your answer is A: Heat must be added or removed

Explanation:

For example...

To change water from a liquid to a solid, you have to change its molecular composition and change the bondages between the Hydrogen and Oxygen molecules...

This is only done when you add heat / remove through Vaporization / Condensation!

To change a substance's state is a REVERSIBLE process meaning you have to add or remove energy (heat) to change its state!

c) 50% there are four chromosomes. after crossing over, 2 of the four have been changed. that means any gamete has a 2 in 4 chance or 50% chance of receiving the mutated chromosome.

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