MCQ
The $pH $ of ${10^{ - 8}}$ molar aqueous solution of $HCl$ is
- A$ - 8$
- B$8$
- ✓$6 > 7$ (Between $6 $ and $7$)
- D$7 > 8$ (Between $7 $ and $8$)
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Given : $\Delta H _{ f }^{\ominus}\left( Al _2 O _3\right)=-1700\,kJ\,mol ^{-1}$
$\Delta H _{ f }^\theta\left( Fe _2 O _3\right)=-840\,kJ\,mol ^{-1}$
Molar mass of $Fe , Al$ and $O$ are $56,27$ and $16\,g\,mol ^{-1}$ respectively.
If the oxidation number of metal in the salt was $3$, what would be the new oxidation number of metal ?