Question

why only gold foil is used in Rutherford's experiment as other metals are also malleable so why only gold?

Answer 1

Dear student

There are two reasons for using a gold foil in the rutherford's experiment.
First of all gold is very malleable because of which a very thin layer of gold can be drawn easily. Other metals are also malleable but the malleability of gold is appropriate for creating the thin sheets.
Also the gold atoms are heavy, because of which they can with stand the force with which the fast moving electrons will be striking the thin sheet. Gold being a heavy metal as well as being so much malleable can satisfy both the conditions and thus will be used in the experiment.

Regards