What is the reaction called in which ethanol reacts with acetic acid in the presence of concentrated $H_{2}SO_{4}$ to form ethyl acetate and water?

$(i)$ Distinguish between saturated hydrocarbons and unsaturated hydrocarbons with the help of the combustion process.
$(ii)$ Write the chemical names of $C_{4}H_{10}$ and $C_{2}H_{2}$ and draw their structures.

$A$ colourless gas '$X$' has a formula $C_{3}H_{6}$. It decolourises bromine water. Write the chemical name of '$X$'.

Which of the following is the correct match between List-$I$ and List-$II$?

List-$I$	List-$II$
$1$. Hydroxyl group	$a$. $>C=O$
$2$. Aldehyde group	$b$. $-OH$
$3$. Carboxylic acid group	$c$. $-CHO$
$4$. Ketone group	$d$. $-COOH$

Write true or false for the following statement:
Two pairs of electrons are shared between two nitrogen atoms to form a nitrogen molecule.

Buckminsterfullerene is an allotropic form of