Total number of enol forms possible for the compound formed during the given reaction will be (including stereoisomers):
$CH_3MgBr + CH_3CH_2COCl \to$

Action of hydrogen chloride on $CH_3-C(CH_3)=CH_2$ and on $CH \equiv CH$ will predominantly give the compounds,respectively:

Match the following reactions in List-$I$ with their products in List-$II$:
| List-$I$ | List-$II$ |
| :--- | :--- |
| $A. HC \equiv CH \xrightarrow{Hg^{2+}, H^{+}/H_{2}O}$ | $I. H_{3}C-COOH$ |
| $B. CH_{4} \xrightarrow{O_{2}, Mo_{2}O_{3}, \Delta}$ | $II. CH_{3}-CO-CH_{3}$ |
| $C. (CH_{3})_{2}C=C(CH_{3})_{2} \xrightarrow{O_{3}, Zn, H_{2}O}$ | $III. H_{3}C-CHO$ |
| $D. CH_{3}-CH=CH-CH_{3} \xrightarrow{KMnO_{4}, H^{+}}$ | $IV. HCHO$ |

The octane number is ...........

$CH_2(COOH)_2 \xrightarrow{P_4O_{10}, \, 150^\circ C} X$
Compound $(X)$ is

What is the number of moles of $sp^2$ hybrid carbon atoms in one mole of $hexa-1,4-diyne$?