Question

Which isomer of bromobutane has the lowest boiling point?

Answer 1

Tert$-$butyl bromide isomer of bromobutane has lowest boiling point. Isomers are molecules with identical molecular formulas, that is, the same number of atoms of each element but distinct arrangements of atoms in space. Isomerism is the existence or possibility of isomers.

Complete answer:
The boiling point of the compound is low if the compound has more branching. Tert$-$butyl bromide has lower boiling point because it has a spherical shape. As a result surface area decreases leading to smaller van der Waals forces between their molecules. Tertiary butyl bromide has the highest branching, so it has a low boiling point.
$n -$butyl Bromide have stronger intermolecular forces because butyl Bromide is a straight chain molecule. As a result intermolecular forces become weaker resulting in a lower boiling point.
$n -$tert$-$Butyl bromide is an organic compound with the formula $M{e_3}CBr$. The molecule features a tert-butyl group attached to a bromine substituent. This organobromine compound is used as a standard reagent in synthetic organic chemistry. It is a colorless liquid. It acts as a starting molecule for nucleophilic substitution reactions and acts as an alkylating agent. It has explosive characteristics and has low ignition temperature.
Butyl bromide is an isomer of ${C_4}{H_9}Br$ which has the highest boiling point and tertiary butyl bromide is another isomer the lowest boiling point.

Note:
Tert-Butyl bromide used to study the massive deadenylation of adenine based-nucleosides induced by halogenated alkanes under physiological conditions. $2 -$Bromo$- 2 -$methylpropane causes the massive deadenylation of guanine based-nucleosides and massive deadenylation of adenine based-nucleosides.