MCQ
Vitamin ${B_{12}}$ contains metal
- A$Ca\, (II)$
- B$Zn \,(II)$
- C$Fe\, (II)$
- ✓$Co \,(III)$
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
| List-$I$ | List-$II$ |
| $\mathrm{P}_2 \mathrm{O}_3+3 \mathrm{H}_2 \mathrm{O} \rightarrow$ | $\mathrm{P}(\mathrm{O})\left(\mathrm{OCH}_3\right) \mathrm{Cl}_2$ |
| $\mathrm{P}_4+3 \mathrm{NaOH}+3 \mathrm{H}_2 \mathrm{O} \rightarrow$ | $\mathrm{H}_3 \mathrm{PO}_3$ |
| $\mathrm{PCl}_5+\mathrm{CH}_3 \mathrm{COOH} \rightarrow$ | $\mathrm{PH}_3$ |
| $\mathrm{H}_3 \mathrm{PO}_2+2 \mathrm{H}_2 \mathrm{O}+4 \mathrm{AgNO}_3 \rightarrow$ | $\mathrm{H}_3 \mathrm{PO}_4$ |