Acetylene reacts with bromine in the presence of ${\mathrm{CCl}}_4$:

Write the condition for the reaction of addition of hydrogen to ethylene. Write the balanced chemical equation of the reaction.

Mention one use of CNG. 

Given below are two statements:

Statement-I : $2$ -methylbutane on oxidation with ${\mathrm{KMnO}}_4$ gives $2$ -methylbutan-$2$-ol.

Statement-II : $\mathrm{n}$ -alkanes can be easily oxidised to corresponding alcohol with ${\mathrm{KMnO}}_4$.

Choose the correct option :

Complete and balance the following equation. State the conditions wherever necessary.

${\mathrm{CaC}}_2+{\mathrm{H}}_2\mathrm{O}\to \_\_\_\_\_$

Represent the union of two sets by Venn diagram for each of the following.

$X=\{x | x$ is a prime number between $80$ and $100\}$

$Y=\{y | y$ is an odd number between $90$ and $100\}$