MCQ
Would gaseous $ HCl$ be considered as an Arrhenius acid
- AYes
- ✓No
- CNot known
- DGaseous $HCl$ does not exist
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Which of these structures is practically not a valid canonical structure for formaldehyde ?
| Column $-I$ | Column $-II$ |
| (Atomic number) | (Position of element in Periodic table) |
| $(A)$ $Z = 37$ | $(P)$ $p-$ block |
| $(B)$ $Z = 42$ | $(Q)$ $f-$ block |
| $(C)$ $Z = 34$ | $(R)$ $d-$ block |
| $(D)$ $Z = 92$ | $(S)$ $s-$ block |

$STATEMENT$-$2$: In water, orthoboric acid acts as a proton donor.
$CO(g) + \frac{1}{2}{O_2}(g)\, \to \,C{O_2};\,\,\,\Delta H = 135.2\,kcal$
Then heat of formation of $CO(g)$ is .....$ kcal$