MCQ
The energy required to release $ 1$ electron from $H{e^ + }$ is ............ $\mathrm{eV}$
- A$+ 54.4$
- ✓$-13.6$
- C$+ 27.2$
- DCannot be predicted
✓
Answer
Correct option: B.
$-13.6$
b
(b)$E = - \frac{{13.6}}{{{n^2}}}\,\,for\,\,H{e^ + }\,\,n = 1$
(b)$E = - \frac{{13.6}}{{{n^2}}}\,\,for\,\,H{e^ + }\,\,n = 1$
$E = - \frac{{13.6}}{{{1^2}}} = - 13.6\,eV$.
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Explore more
Similar questions
In the Newman projection for $2,2$-dimethylbutane $Image$ ${X}$ and ${Y}$ can respectively be
→$(A)$ $\mathrm{H}$ and $\mathrm{H}$
$(B)$ $\mathrm{H}$ and $\mathrm{C}_2 \mathrm{H}_5$
$(C)$ $\mathrm{C}_2 \mathrm{H}_5$ and $\mathrm{H}$
$(D)$ $\mathrm{CH}_3$ and $\mathrm{CH}_3$
${N_{2(g)}}\, + \,3{H_{2(g)}} \rightleftharpoons \,2N{H_{3(g)}}$
→$56\ g$ of nitrogen and $8\ g$ of hydrogen gas are heated in a closed vessel. At equilibrium, $34\ g$ of ammonia are present. The equilibrium number of moles of nitrogen, hydrogen and ammonia are respectively
Carbogen is
The aromatic compound among the following is:
Boric acid is an acid because its molecule
If the atomic weight of an element is $ 23 $ imes that of the lightest element and it has $11$ protons, then it contains
→Dissociation constant for a monobasic acid is $10^{-4}$ . What is the $pH$ of the monobasic acid ? (If $\%$ dissociation $= 2\,\%$ )
→General formula of alkyne is
Molarity $(M)$ of an aqueous solution containing $\mathrm{x} g$ of anhyd. $\mathrm{CuSO}_4$ in $500 \mathrm{~mL}$ solution at $32^{\circ} \mathrm{C}$ is $2 \times 10^{-1} \mathrm{M}$. Its molality will be. . . . . .$\times 10^{-3} \mathrm{~m}$ (nearest integer). [Given density of the solution $=1.25 \mathrm{~g} / \mathrm{mL}$.]
→The volume of 0.5M aqueous NaOH solution required to neutralize 10ml of 2M aqueous HC1solution is: