Why is DNA insoluble in ethanol, on a molecular level?

cuz ur dog did da homework

ethanol is nonpolar while DNA is polar and in the saying "like disolves like" the same applies here. So DNA is soluble in water because it is polar.

and if I didn't make it clear this is the same reason that DNA is NOT soluble in ethanol since DNA is polar and ethanol is not.

DNA is insoluble in ethanol due to the nature of the interactions between ethanol molecules and the structure of DNA at a molecular level. To understand this, we need to explore the properties of both DNA and ethanol.

DNA is a long, double-stranded helical molecule composed of nucleotides. Each nucleotide contains a phosphate group, a sugar molecule (deoxyribose), and a nitrogenous base (adenine, thymine, cytosine, or guanine). The backbone of DNA is made up of alternating phosphate and sugar groups, while the nitrogenous bases protrude from the backbone. These bases can pair up with complementary bases on the opposite strand of DNA, forming a stable double helix structure.

Ethanol, on the other hand, is a polar organic compound with a hydroxyl (OH) group. Its polar nature arises due to the electronegativity difference between carbon and oxygen, making the oxygen atom partially negative and the hydrogen atom partially positive. This polarity allows ethanol to form hydrogen bonds with other polar molecules or functional groups.

When DNA is placed in ethanol, the polar nature of ethanol molecules disrupts the hydrogen bonding between the nitrogenous bases of DNA. The OH group of ethanol can form hydrogen bonds with the negatively charged phosphate groups and the polar sugar molecules of DNA. These interactions compete with the hydrogen bonding between the nitrogenous bases, preventing the DNA strands from staying together and leading to the precipitation or aggregation of DNA.

In summary, the insolubility of DNA in ethanol is due to the disruptive hydrogen bonding interactions that ethanol forms with the phosphate and sugar groups of DNA, causing the DNA to aggregate and separate from the solvent.