Alchemists were medieval scholars and philosophers who were the forerunners of modern-day chemists. many tried repeatedly to transform lead (atomic number 82) into gold (atomic number 79). explain why they never did succeed.

Answer is: because they were using simple chemical reactions to transform elements, but that is possible only with nuclear reactions, which in that time were not possible to conduct.

Nuclear reactions can produce new elements, because number of protons and neutrons is changed, lead and gold have different atomic and mass numbers.

The electrons of an atom participates in a chemical reaction, chemical reactions involve the rearrangement of electrons, because there is transfer, loss, gain and sharing of electrons in chemical reactions, new elements are not formed.

the answer is na (sodium)