A deodorant contains solution of perfume and alcohol What happens to the perfume when it is mixed with the alcohol?
A)it boils
B)It dissolves
C)it freezes
D)It melts

B

Explanation:

Alcohol helps break down perfume ingredients. Break down is a close synonym for dissolve. So, B is the correct answer.

D)  Strontium-90 atoms spontaneously emit beta particles.

Explanation:

The evidence that indicates that the nuclei of strontium - 90 atoms are unstable is that they spontaneously emit beta particles.

For every atomic nucleus, there is a specific proton to neutron ratio which ensures stability of the nucleus.

Any nucleus with a neutron/proton combination different from its stability ratio will be unstable and split into one or more other nuclei.

Strontium  - 90 atoms are an example of this. To attain stability, they emit beta particles spontaneously.