Question

Explain what result would you expect if you accidentally extracted the mixture in the reverse order (first using aqueous hcl, then aqueous naoh, then aqueous sodium bicarbonate)?

a. only the neutral compound would be separated from the others.
b. the stronger acid and the weaker acid would not be separated from each other.
c. the neutral compound and the base would not be separated from each other.
d. the neutral compound and the weaker acid would not be separated from each other.
e. the neutral compound and the stronger acid would not be separated from each other.

Answer 1

Using aqueous HCl first would result in the neutral compound and the stronger acid not being separated because HCl will not convert the base or weaker acid into a form that could be easily removed, and subsequent steps will not rectify this.

Step-by-step explanation:

If a mixture was extracted in reverse order, starting with aqueous HCl, followed by aqueous NaOH, and then aqueous sodium bicarbonate, you would expect that the neutral compound and the stronger acid would not be separated from each other. This is because the addition of HCl, a strong acid, would not protonate or convert either the base or the weaker acid into ionic forms that could be easily separated by aqueous solutions. Subsequently, using NaOH would deprotonate the stronger acid, assuming it is not a super strong acid, and extract both the stronger acid (now deprotonated) and the base as a salt form, leaving behind the neutral compound. However, because the weaker acid has already reacted with the HCl to form a salt, the NaOH would not further separate it, resulting in the stronger acid and weaker acid remaining together. Lastly, the addition of bicarbonate would not change this situation as it is typically used to neutralize any remaining strong acid or to separate a weaker acid from a mixture.