Name the distinguishing reaction of an alkane from an alkene.

What are $X$ and $Y$ respectively in the following sets of reactions?
$I. \ CH_3CH_2CH_2OH \xrightarrow{PBr_3} X$
$II. \ CH_3CH=CH_2 \xrightarrow{HBr, (C_6H_5COO)_2} Y \text{ (major)}$

Predict the product $(A)$ of the following reaction:

What is the number of $\sigma$ and $\pi$ bonds in $Pent-1-en-4-yne$?

The number of isomeric tetraenes ($NOT$ containing $sp$-hybridized carbon atoms) that can be formed from the following reaction sequence is.....

Answer the following questions:
$(i)$ What is the bond length of $C-C$,$C=C$,and $C\equiv C$?
$(ii)$ What will be the effect on bond length as bond multiplicity increases?
$(iii)$ What is the relation between reactivity of compound,bond strength and bond order between two carbon atoms?
$(iv)$ What is the rate of reaction of $Cl_2, Br_2,$ and $I_2$ with $CH_2=CH_2$?
$(v)$ What is the difference between $2-$butyne and $1-$butyne? By which test can we distinguish between these two?
$(vi)$ Which real product is obtained on hydrolysis of alkyne? Why?
$(vii)$ Give the structure and $IUPAC$ name:
$(a)$ Vinyl chloride
$(b)$ Vinyl cyanide
$(c)$ Glyoxal
$(d)$ Silver acetylide
$(e)$ Diacetyl
$(f)$ Glycol