Question

what do these two changes have in common? burning a marshmallow over a campfire bleaching clothes select all that apply. both are only physical changes. both are chemical changes. both are caused by heating. both are caused by cooling.

Explanation:

Burning a marshmallow breaks down its organic components into new substances (like carbon, water vapor) via combustion, which is a chemical change. Bleaching clothes uses chemical reactions (oxidation) to break down dye molecules, also forming new substances and being a chemical change. Burning uses heating, but bleaching does not require heating, so the heating/cooling options are incorrect, and they are not physical changes (no new substances form in physical changes).

Answer:

Both are chemical changes.