Give the formula and names of A, B, C and D in the following equations:

(a)

$\text{CH}$4 \xrightarrow[\text{-HCl}]{\text{Cl}2} \text{A} \xrightarrow[\text{-HCl}]{\text{Cl}2} \text{B}\xrightarrow[\text{-HCl}]{\text{Cl}2} \text{C}\xrightarrow[\text{-HCl}]{\text{Cl}_2} \text{D}

(b)
$\text{C}$2\text{H}2 \xrightarrow{\text{H}2} \text{A} \xrightarrow{\text{H}2} \text{B}\xrightarrow[\text{-HBr}]{\text{Br}2} \text{C}\xrightarrow[\text{-HBr}]{\text{Br}2} \text{D}

(c)
$\text{C}$2\text{H}4 + \text{B} \xrightarrow[\text{Nickle}]{200\degree\text{C}} \text{C}2\text{H}6

Write the name and formula of the product formed in each case below:

(a) C₂H₄ + Cl₂ ⟶ ……………

(b) C₂H₅I + KOH (alc.) $\xrightarrow{\Delta}$ ……………

(c) H₂C=CH₂ $\xrightarrow{\text{alc. KMnO}_4}$ ……………

(d) H₂C=CH₂ + HBr ⟶……………

Name three compounds formed by ethene and give one use of each compound.

What are the sources for alkynes? Give the general formula of alkynes.