Answer:
The correct answer is d. As the chocolate bar changes from a solid to a liquid the particles move around more.
Explanation:
When a chocolate bar melts, it suffers a <u>physical</u> change: a change of state from solid to liquid. In the liquid state, the particles move around more, because they have more kinetic energy (more velocity) and more freedom to move than in solid state. Thus, as the solid became into a liquid, the particles move more.
The fact that when in solution <span>C</span>₂<span>H</span>₅<span>OH conducts electricity means that it is an electrolyte so you can automatically cross out A and C (the definition of an electrolyte is a substance that will conduct electricity when in a solution). I think the correct answer is B due to the -OH group (the - indicates a covalent bond) which allows the molecule to give up a proton (H</span>⁺).
I hope this helps. Let me know if anything is unclear.
1.c 2.d 3.b 4.a 5.a 6.a 7.b 8.b 9.d 10.
