Question

changes in matter
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which of these is an example of a physical change?
○ sugar dissolving in warm water
○ iron rusting in the presence of moist air
○ wood burning in the presence of oxygen
○ baking soda reacting with acid to form a gas

Explanation:

A physical change alters matter's form but not its chemical identity. Sugar dissolving in water is a physical change because the sugar molecules disperse but remain sugar, and the change can be reversed (by evaporating the water). The other options are chemical changes: iron rusting forms new iron oxide, wood burning produces new carbon-based compounds, and baking soda reacting with acid creates new gaseous and dissolved chemical products.

Answer:

sugar dissolving in warm water