Which of the following materials is necessary to stop an alpha particle? a. three feet of concrete c. single sheet of aluminum foil b. three inches of lead d. single sheet of paper

d) Single sheet of paper

Explanation:

Since alpha particles are heaviest particles that comes out from nucleus during the radioactive decay so out of all these are having least energy.

So here in this we can say that penetration power of alpha particles is least and it can be stopped by least thickness due to less penetration power and least energy

So here we can say that alpha particles can be stopped just by using the least thickness.

So out of all given options we can have

d) Single sheet of paper

ammonium chloride & tallow