MCQ
Most acidic among given compound is
- A$Pr(OH)_3$
- B$Gd(OH)_3$
- C$Sm(OH)_3$
- ✓$Er(OH)_3$
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$H{_2(g)} + 2ICl_{(g)} \to 2HCl_{(g)} + I_{2(g)}$
This reaction is of first order with respect to $H_{2(g)}$ and $ICl_{(g)}$ , following mechanisms were proposed
Mechanism $A$ :
$H{_2(g)} + 2ICl_{(g)} \to 2HCl_{(g)} + I_{2(g)}$
Mechanism $B$ :
$H_{2(g)} + ICl_{(g)} \to HCl_{(g)} + HI_{(g)}$ ; Slow
$HI_{(g)} + ICl_{(g)} \to HCl_{(g)} + I_{2(g)}$ ; Fast
Which of the above mechanism $(s)$ can be consistent with the given information about the reaction
| Acid | $K_a$ |
| $HCN$ | $6.2\times 10^{-10}$ |
| $HF$ | $7.2\times 10^{-4}$ |
| $HNO_2$ | $4.0\times 10^{-4}$ |
Correct order of increasing base strength of the base $CN^-,F^-$ and $NO_2^-$ will be