A lab experiment shows: merge a litmus paper in a base solution will turn it into blue.

1.a sign of physical reaction because no
changing in the structure of paper

2.a sign of chemical reaction because of
changing in color

3.no reaction occur

2.

Explanation:

When you put the paper in a solution, it will turn blue if it is basic, or red if it is acidic. If it does not change color, it is fairly neutral.

well in order to answer this question you have to provide more information < 3

they are both synthetic elements

explanation:

d