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3 years ago

WILL BE MARKED BRAINLIEST IF U ANSWER CORRECT

Chemistry

2 answers:

Ludmilka [50]3 years ago

8 0

Answer:

DNA is polar due to its highly charged phosphate backbone. Its polarity makes it water-soluble (water is polar) according to the principle "like dissolves like". ... This fact makes water a very good solvent for charged compounds like salts.

Your DNA's sugar phosphate backbone is charged. By adding salt, we help neutralize the DNA charge and make the molecule less hydrophilic, meaning it becomes less soluble in water. The salt also helps to remove proteins that are bound to the DNA and to keep the proteins dissolved in the water.

It is well known that Ethanol has a lower dielectric constant than water, making it to promote ionic bond formations between the Na+ (from the salt) and the PO3- (from the DNA backbone), further, causing the DNA to precipitate.

Explanation:

Ideally DNA needs to be precipitated with pellet and should not remain in supernatant. DNA is acidic in nature and therefore, needs optimum salt concentration in the buffer to be pelleted from a solution. At very low salt concentration or without salt DNA would remain in supernatant.

Alla [95]3 years ago

4 0

Explanation:

Because of this, DNA and RNA can easily dissolve in water. ... Adding ethanol helps the Na+ and PO3- ions come together, because ions travel easier in ethanol than water. The supernate is removed and new ethanol is added in the second washing. This removes any residual salt that remained on the pelleted DNA.

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1) The concentration of HCl = 0.1 M.

2) The table that can be used to organize the information correctly is C.

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1) The concentration of HCl:

We know that the no. of millimoles of the acid is equal to the no. of millimoles of the base at the neutralization point.

which means that: (MV)HCl = (MV)NaOH,

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∴ M of HCl = (MV)NaOH/V of HCl = (0.2 M)(12.5 mL)/(25.0 mL) = 0.1 M.

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Table A and B are the same and reported volume of HCl and NaOH is wrong.

Table C is right, contain the correct volumes and concentration of NaOH and missed the concentration of HCl which is 0.1 M.

Table D reported the volume and the concentration of HCl wrongly and also the concentration of NaOH. The data reported of HCl and NaOH is reversed.

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