It depends on the solid. For example, iodine changes from a solid to a gas, which is called sublimation. However, not all solids will sublime.
Heat will cause a solid to melt into a liquid.
liquid
it depends on the solubility of the solid in that specific liquid. If the solid is highly soluble, then it should dissolve completely forming a solution, possibly coloured. If it is not, then it will just sit in the liquid.
liquid
Heat is added to a solid to make a liquid... this is called melting. some additional liquid (water,ethanol,acid…) also change solid into a liquid.
usually heat the liquid
No
heat it up!
no it can be a liquid as well we can mix a liquid with another liquid to make a solution
baking it would transform it into solid
AGAR
Absorbs heat and melts.