Answer: physical change.
Explanation:
A physical change is defined as a change in which there is alteration in shape, size etc. No new substance gets formed in these reactions. Example: melting of ice
A chemical change is defined as a change in which a change in chemical composition takes place. A new substance is formed in these reactions. Example: Combustion
As the sugar cubes dissolves into a container of warm water, it only changes its state from solid to aqueous and no new substances are being formed. Thus it is a physical change.
