For the following compounds,write structural formulas and $IUPAC$ names for all possible isomers having the number of double or triple bonds as indicated:
$(a)$ $C_4H_8$ (one double bond)
$(b)$ $C_5H_8$ (one triple bond)

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

What is the degree of unsaturation (double bond equivalent) in compound $(A)$?

Identify the product $(C)$ in the following series of reaction:
$\text{Cyclopentane}$ $\xrightarrow{Br_2, hv} A$ $\xrightarrow{\text{alc. KOH}} B$ $\xrightarrow{\text{NBS}} C$

The correct statement is

Identify the final product $(B)$ in the following reaction sequence:
$1\text{-bromo-}2\text{-methylcyclobutane}$ $\xrightarrow{\text{alc. KOH}} A$ $\xrightarrow{\text{ozonolysis}} B$