In which reaction is an atom of one element converted into an atom of another element

Explanation:

Nuclear transmutation is the conversion of one chemical element or an isotope into another chemical element.

Explanation:

nuclear decay reaction, also called radioactive decay, an unstable nucleus emits radiation and is transformed into the nucleus of one or more other elements. ... Nuclear decay reactions occur spontaneously under all conditions, whereas nuclear transmutation reactions are induced.Sep 5, 2021

2fe + 3h2so4 -> fe2(so4)3 + 3h2

it is necessary to balance equations in order to get the proper amount of reactants as well as products in order not to make a miscalculation.

you cannot change the subscripts as that would change the substance itself. for instance, diatomic elements such as h2 only have the subscript two when a gas. another example would be so4, if you were to change the subscript, the element would no longer be sulfate.

we change the coefficients instead as that only changes the number of molecules rather than the substance itself.

hope this !