Question

Which of the following sentences represents a physical change? sugar dissolves in coffee iron rusts gasoline burns in an engine a candle burns

Answer 1

The sentence that represents a physical change is sugar dissolves in coffee.
The reason why this is a physical, and not a chemical change is because the sugar completely changed its state - it used to be solid, but then it melted into the coffee and became liquid.
The other options are all chemical changes.

Answer 2

• Physical changes example is sugar dissolves in coffee
• Chemical changes examples are iron rusts, gasoline burns in an engine and a candle burns.

Explanation.

• Physical changes depend on only physical state, not on composition, which can be separated by physical means while chemical changes depend on composition and only separated by chemical ways.
• As in case of iron rusting, gasoline and candle burn are cases chemical changes bcz they convert into another substance whose composition is different from other as compare to sugar which has same composition in coffee ,only state is changed from solid to liquid.