Question

The pictures show what happens when baking soda is mixed with vinegar.



image

Is this a chemical or physical change and why?



A.
This is a chemical change because the parts of the mixture separated.

B.
This is a chemical change because a new substance formed as a result.

C.
This is a physical change because the baking soda dissolved in the vinegar.

D.
This is a physical change because bubbles were produced when the baking soda mixed with the vinegar.

Answer 1

Answer: B.

This is a chemical change — acetic acid reacts with sodium bicarbonate to form new substances (carbon dioxide gas, water, and sodium acetate). The bubbling is CO2 being produced, evidence of a chemical reaction.