Question

Melting, freezing, and boiling are _____________ changes. Question 3 options: A. compound

Answer 1

Melting, freezing, and boiling are PHYSICAL changes. Reason why, you can SEE their PHYSICAL appearance change. Melting, you can see a solid (ice) melt, and turn into a liquid (that's a physical change). Freezing, is when a liquid (possibly water) becomes a solid. It's features change, thus it's a physical change. Boiling, when something is boiled you can see it physically BUBBLE. It heats up, and you can see steam escape from it. This is a physical change, but when you turn it off, the water goes back to normal. But not exactly. When you boil water, you're cleaning and purifying the water. So it become purified drinking water. Also just a tip, when boiling water, make sure the temperature is above 185° F (85° C) so it'll be able to kill all bacteria.
(I wrote this myself, it's my work.) 
Good luck with your studies, hope this helps!! ^-^

Answer 2

Melting freezing and boiling are molecular changes