AP Chemistryeasymcq1 pt
Which observation indicates a chemical change occurred?
A.A gas forms when two clear liquids mix
B.Ice melts at room temperature
C.Water evaporates from a dish
D.Salt dissolves in water
Explanation
Core Concept
Bubbling without heating signals new substances being produced — a chemical change. Color shifts and precipitates are the other classic signs.
Correct Answer
AA gas forms when two clear liquids mix
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