MCQ
For which of the following, the radius will same as for hydrogen atom having $n = 1$
- A$He^+, n = 2$
- B$Li^{+2}, n = 2$
- ✓$Be^{+3}, n = 2$
- D$Li^{+2}, n = 3$
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| List $I$ (Fuels) | List $II$ (Composition) |
| $A.$ Water gas | $i.$ A mixture of $CO$ and $N_2$ |
| $B.$ Producer gas | $ii.$ Methane |
| $C.$ Coal gas | $iii.$ A mixture of $CO$ and $H_2$ |
| $D.$ Natural gas | $iv.$ A mixture of $CO$, $H_2$, $CH_4$ and $CO_2$ |
$A\,-\,B\,-\,C\,-\,D$ Respectively