Why chilled ethanol is used during the isolation of the desired gene?

Chilled ethanol is used because:

1. Chilled ethanol has a lower polarity than water.
2. The screening charges imposed by water are disrupted when it is added to the solution.
3. Phosphate's electrical attraction to any positive ions (Na+) in solution becomes strong enough to create a stable ionic connection and DNA precipitates.
4. Ethanol precipitation is a common method for purifying and concentrating nucleic acids.
5. DNA spooling is the term for this process.