8. Which of the following results in a chemical reaction?

Question

1. adding vinegar to water
2. leaving milk to go sour
3. stirring sugar with tea
4. mixing salt with water

Answer 1

Hi Sarah,

Recall that a chemical reaction can be typically explained as something that cannot be undone.

If we add vinegar to water, stir sugar with tea, or mix salt with water, (answers 1,3, & 4) we can separate the pieces out again by taking advantage of their different boiling points. But, with leaving milk to go sour (answer 2), we can't undo the souring. The milk is chemically changed when it sours.

Thus, answer 2 results in a chemical reaction.