An ion with mass number 56 contains 3 units of positive charge and 30.

1.	An ion with mass number 56 contains 3 units of positive charge and 30.4% more neutrons than electrons. Assign symbol to the ion.
Answer» Let the 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 + 30.4x/100 = x + 0.304 x Now, mass number of ion = Number of protons + Number of neutrons = (x + 3) + (x + 0.304 x) ∴ 56 = (x + 3) + (x + 0.304 x) or 2.304 x = 56 – 3 = 53 x = 53/2.304 = 23 Atomic number of the ion (or element) = 23 + 3 = 26 The element with atomic number 26 is iron (Fe) and the corresponding ion is Fe³⁺ .

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

Answer»

Let the 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 + 30.4x/100 = x + 0.304 x

Now,

mass number of ion = Number of protons + Number of neutrons

= (x + 3) + (x + 0.304 x)

∴ 56 = (x + 3) + (x + 0.304 x) or 2.304 x = 56 – 3 = 53

x = 53/2.304 = 23

Atomic number of the ion (or element) = 23 + 3 = 26

The element with atomic number 26 is iron (Fe) and the corresponding ion is Fe³⁺ .