Question
The first $$\left( {I{E_1}} \right)$$ and second $$\left( {I{E_2}} \right)$$ ionisation enthalpies $$\left( {kJ/mole} \right)$$ of element, $$A$$ are given below.
|
$$A$$ |
| $$I{E_1}$$ |
750 |
| $$I{E_2}$$ |
1500 |
In an experiment $$\frac{1}{{12}}\,mole$$ of $$A$$ atom in vapour phase absorb $$100\,kJ$$ of energy. So that it forms a mixture of $${A^ + }$$ and $${A^{2 + }}$$ ions. Energy utilized to form $${A^{2 + }}$$ from $${A^ + }$$ in experiment is
A.
1500 $$kJ$$
B.
750 $$kJ$$
C.
62.5 $$kJ$$
D.
37.5 $$kJ$$
Answer :
37.5 $$kJ$$
Solution :
$$\eqalign{
& {\text{Energy required to convert}}\,A\,\,{\text{to}}\,\,{A^ + } \cr
& = \frac{1}{{12}} \times 750 \cr
& = 62.5\,kJ \cr
& {\text{Remaining energy to convert}}\,{A^ + }\,{\text{to}}\,{A^{2 + }} \cr
& = 100 - 62.5 \cr
& = 37.5\,kJ. \cr} $$