# In the distillation of petroleum spirit, what property is exploited to separate the different components of the spirit?

$\text{The differential volatility of its components............?}$
When we use petroleum ether in the laboratory, typically, we use $40$ ""^@C-60 ""^@C boiling point pet ether, $60$ ""^@C-80 ""^@C boiling point pet ether, $100$ ""^@C-120 ""^@C boiling point pet ether. The lower boiling pet ethers are the isomeric $C 4 - C 5$ alkanes and olefins, $60$ ""^@C-80 ""^@C boiling point pet ethers are the isomeric $C 6 - C 7$ alkanes and olefins.
An inorganic chemist will often take petroleum ethers from a supplier, and treat this with acidified, aqueous $K M n {O}_{4}$ over an extended period (so as to oxidize any olefinic component). After 24-48 hours, the pet ether would be separated, carefully washed with fresh water, and then VERY carefully dried. The petroleum ether would then be used as $\text{olefin-free petroleum ether}$ for the synthesis of certain metal complexes.