An ion with mass number `56` contains `3` units of positive charge and `30.4%` more neutrons then electrons. Assign the symbol to this ion.

Explanation

Let to no. of electrons in the ion = x
`:. " "` the no. of the protons = x + 3 (as the ion has three units positive charge)
and the no. of neutrons `=x+(30.4 x)/(100) = x + 0.304 x `
Now, mass no, of ion = No. of protons + No. of neutrons
`=(x+3) + (x+ 0.304x) `
`:. " " 56 = (x+3) + (x+0.304x) or 2.304 x = 56-3 = 53 `
`x=(53)/(2.304)=23`
Atomic no. of the ion (or element) = 23 +3 26
The element with atomic number 26 is iron (Fe) and the corresponding ion is `Fe^(3+)`