Q.Statement I : Butanone, upon protonation at oxygen atom result in a ...
The correct answer is option a
Statement I: Butanone, upon protonation at the oxygen atom, results in a pair of stereoisomers. This statement is correct. When butanone (
) is protonated at the oxygen atom of the carbonyl group, it forms two stereoisomers.
Statement II: Presence of a lone pair of electrons at oxygen is responsible for protonation.This statement is also correct. The lone pair of electrons on the oxygen atom of the carbonyl group is responsible for accepting a proton (H⁺) during the protonation process. Statement II is a correct explanation for Statement I. The presence of a lone pair of electrons on oxygen enables protonation, leading to the formation of stereoisomers.Therefore, the correct answer is option (a): Both Statement I and Statement II are correct, and Statement II is the correct explanation of Statement I.
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Q.Statement I : Butanone, upon protonation at oxygen atom result in a ...
Statement I: Butanone, upon protonation at the oxygen atom, results in a pair of stereoisomers.
Statement II: The presence of a lone pair of electrons at oxygen is responsible for protonation.
Explanation:
Protonation of Butanone:
Butanone, also known as methyl ethyl ketone, has the chemical formula C4H8O. It contains a carbonyl group (C=O) with an oxygen atom that has a lone pair of electrons. Protonation refers to the addition of a proton (H+) to a molecule.
Stereoisomers:
Stereoisomers are compounds that have the same molecular formula and connectivity of atoms but differ in the arrangement of atoms in space. In the case of butanone, protonation at the oxygen atom can lead to the formation of stereoisomers.
Explanation of Statement I:
Statement I is correct. Protonation of butanone at the oxygen atom results in the formation of a pair of stereoisomers. This is because the addition of a proton to the oxygen atom can change the spatial arrangement of atoms around the carbonyl group, resulting in different stereoisomeric structures.
Explanation of Statement II:
Statement II is also correct. The presence of a lone pair of electrons at the oxygen atom is responsible for protonation. The lone pair of electrons on the oxygen atom acts as a nucleophile, attracting the positively charged proton (H+). This leads to the formation of a new bond between the proton and the oxygen atom, resulting in protonation.
Explanation of the Correct Answer:
The correct answer is option B: Both Statement I and Statement II are correct, but Statement II is not the correct explanation of Statement I.
While both statements are individually correct, Statement II does not directly explain why protonation at the oxygen atom of butanone leads to the formation of stereoisomers. The formation of stereoisomers is a result of the change in spatial arrangement of atoms upon protonation, which is not directly attributed to the presence of a lone pair of electrons. Therefore, Statement II is not the correct explanation of Statement I.
In conclusion, butanone can undergo protonation at the oxygen atom, resulting in the formation of stereoisomers. The presence of a lone pair of electrons at the oxygen atom is responsible for protonation, but it does not directly explain the formation of stereoisomers.
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