Ethanol is used to precipitate nucleic acids in the ratio

Ethanol is used to precipitate nucleic acids in the ratio 2:1 (EtOH:water). Isopropanol is used at a 1:1 ratio. Not as much isopropanol is needed than ethanol to achieve the same outcome. Why is isopropanol more efficient than ethanol in precipitating nucleic acids?

A. Isopropanol is more effective because it is more non-polar and the non-polar chains penetrate the hydrophobic core of nucleic acids more easily than ethanol.

B. Ethanol has a lower molecular weight than isopropanol and therefore more of it is needed to achieve the same outcome of precipitating nucleic acids.

C. Isopropanol has a lower dielectric constant than ethanol, meaning that it makes the water-isopropanol mixture less polar than an ethanol-water mixture and allows nucleic acids to aggregate more readily.

D. Water associates more readily with isopropanol than ethanol because isopropanol, though less polar than ethanol, has a stronger acting OH group that interacts with water more easily.

E. Ethanol is more polar than isopropanol and associates more readily with water, which makes an ethanol/water mix more polar than an isoproanol/water mix, and more ethanol is needed.


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