MCQ
Correct order of $pH$ of $0.1\, M$ solution is
- A$NaCl < NH_4Cl < NaCN < HCl$
- B$NaCN < NH_4Cl < NaCl < HCl$
- C$HCl < NaCl < NaCN < NH_4Cl$
- ✓$HCl < NH_4Cl < NaCl < NaCN$
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| gas | $Ar$ | $Ne$ | $Kr$ | $Xe$ |
| $a /\left( atm \,dm ^{6} \,mol ^{-2}\right)$ | $1.3$ | $0.2$ | $5.1$ | $4.1$ |
| $b /\left(10^{-2} \,dm ^{3}\, mol ^{-1}\right)$ | $3.2$ | $1.7$ | $1.0$ | $5.0$ |
Which gas is expected to have the highest critical temperature?