Verified Answer :

  1. The boiling point is 80°C, and the melting point is 20°C.

    14. [Well I'm not exactly sure what it's asking, but I'll say what I assume it's asking] The substance has changed state from a solid to a liquid, and the particles in the substance start to/continue to gain more energy as it is being added, allowing the particles to move around more.

    I've included a picture that may help a bit.
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