Question

Stirring dry yeast into a bowl of hydrogen peroxide causes bubbles to form. Blowing air into a glass of milk with a straw also causes bubbles to form. One of these is a physical change, and the other is a chemical change. How could you determine which type of change is occurring in each situation?

Answer 1

The first sentence is a chemical change because it is two  component's that when mixed together you make bubbles and the second one is physical because you are making the bubbles cause just setting the straw in there is just doing  nothing  

Answer 2

Answer:

Sample Response: If the reaction is a chemical change, new substances with different properties and identities are formed. This may be indicated by the production of an odor, a change in color or energy, or the formation of a solid.

Explanation:

its what it says on edg