Question

An ion with mass number 37 possesses one unit of negative charge. if the ion conatins 11.1% more neutrons than the electrons, find the symbol of the ion.

Answer 1

Examples of Isotopes:
Isotopes of Hydrogen- Hydrogen – 1, Hydrogen – 2, Hydrogen - 3

Isotopes of Oxygen – Oxygen -16, Oxygen -17, Oxygen -18

Isotopes of Carbon – Carbon – 12, Carbon – 13, Carbon- 14

Isotopes of Chlorine – Chlorine- 35, Chlorine - 37

Isotopes of Fluorine - Fluorine 17, Fluorine 18, Fluorine 19.

Examples of Isobars:

(i)   32 Ce76, 34Se76

(ii) 26Fe58, 27 Ni58 

(iii) 18Ar40 19K40 20Ca40

(iv)11Na24 12Mg24

(v) 27Co64 28Ni64

Answer 2

$\fbox\textcolor{orange}{\texttt{Answer = Cl(37,17)}}$

$\textcolor{indigo}{\texttt{Explanation :-}}$

Suppose no. of electrons = x

no. of neutrons = $x + \frac{11.1}{100}\times{x}\: = \:1.111x$

No. of electrons in the neutral atom = $x - 1$

No. of protons in the neutral atom =$x - 1$

Mass no. = no. of neutrons + no. of protons

ie, $37\:=\:1.111x+x-1$

$2.111x\:=\:37+1\:=\:38$

$x = \frac{38}{2.111}\:=\texttt{18}$

No. of protons = Atomic no. =

$x-1\:=\:18-1\:=\texttt{17}$

Hence the symbol of the ion is: $</h3><h3>\fbox{^{37}_{17}Cl}$