Alison mixes baking soda and vinegar in a clear glass container. She places a blue balloon over the mouth of the container. Which condition tells Alison that a chemical change is taking place?

Question

Alison mixes baking soda and vinegar in a clear glass container. She places a blue balloon over the mouth of the container. Which condition tells Alison that a chemical change is taking place? 
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The balloon fills and expands.
The mixture is cloudy in appearance.
The balloon gets lighter blue as it expands.
The container holds a mixture of a solid and liquid.

GPT 3.5 · Answer

The balloon fills and expands.