Question

During hydrolysis of methyl chloride and acetyl chloride by aqueous NaOH interaction starts by overlapping between respectively (A) \(\sigma\) (filled) \(-\sigma *(\) vacant \()\) and \(\sigma(\) filled \()-\pi *(\) vacant \()\) (B) \(\sigma *\) (vacant) - \(\sigma\) (filled) and \(\sigma\) (filled) \(-\pi\) (vacant) (C) \(\sigma\) (filled) \(-\sigma(\) vacant \()\) and \(\sigma(\) filled \()-\pi(\) vacant \()\) (D) \(\sigma\) (vacant) \(-\sigma\) (fill13ed) and \(\sigma\) (filled) \(-\pi\) (filled)

Short answer

The correct answer for the overlapping interaction during hydrolysis of methyl chloride and acetyl chloride by aqueous NaOH is (A) \(\sigma\) (filled) -\(\sigma^{*}\) (vacant) and \(\sigma\) (filled)-\(\pi^{*}\) (vacant).

Step-by-step solution

Identify the Correct Overlapping Combination for Hydrolysis

During hydrolysis, the nucleophile (in this case, NaOH) attacks the electrophilic carbon. In the reaction, the filled orbital of the nucleophile (hydride ion, i.e., H-) will interact with the vacant orbital of the chlorides to form the sigma bond. According to the given options, we're looking for an interaction where a filled sigma orbital overlaps with a vacant orbital.

Check the Options Against the Identified Overlapping Combination

With our determined pattern of filled sigma and vacant (either sigma* or pi), we look through the options. Option (A) - \(\sigma\) (filled) -\(\sigma^{*}\) (vacant) and \(\sigma\) (filled)-\(\pi^{*}\) (vacant) : This option in the first part contains the correct combination of overlapping for the sigma bonding formed in the hydrolysis of methyl chloride. The second part describes the case for acetyl chloride where a \(\sigma\) (filled) orbital overlaps with a \(\pi^{*}\) (vacant) orbital, possibly forming a \(\pi\) bond. Option (B), (C), and (D) do not follow our overlapping combination identified in Step 1. In (B) and (D), the filled sigma orbital from NaOH could not interact with the filled sigma orbital in the chloride compounds, and in (C), a filled sigma cannot interact with a vacant pi to form a sigma bond.

Choosing the correct answer

As we reviewed the options against our desired overlapping scheme, only option (A) fits the criteria completely. In hydrolysis, the filled sigma interacts with a vacant sigma* orbital in methyl chloride and a vacant pi* orbital in acetyl chloride. Thus, the correct answer is option (A).

Key concepts

Nucleophilic Attack

In chemistry, a nucleophilic attack is a crucial step in many reactions, such as hydrolysis. This is where a nucleophile, which is an electron-rich species, seeks out an electrophile, an electron-deficient species. During hydrolysis with NaOH, the hydroxide ion ( OH^− ) acts as a nucleophile. It attacks the positively charged carbon atom in compounds like methyl chloride and acetyl chloride.
This process triggers further transformations by breaking and forming bonds. For example, the nucleophile's electrons target the electrophilic carbon, kicking off a reaction that leads to a change in the molecule's structure.

• Hydroxide ion ( OH^− ) is a common nucleophile.
• Electrophilic carbons often appear in carbon-halogen bonds.
• A successful attack typically results in the formation of new bonds.

Understanding nucleophilic attack helps in predicting reaction mechanisms and outcomes.

Orbital Overlapping

Orbital overlapping is a fundamental concept in chemistry that explains how bonds form between atoms. When two atoms come close, their atomic orbitals can overlap, allowing electrons to interact. In the context of hydrolysis, this is key for understanding how nucleophiles interact with electrophiles.
For hydrolysis of methyl chloride and acetyl chloride, the filled orbitals from the nucleophile overlap with the vacant orbitals from the electrophile. This bond formation happens through either sigma ( σ ) to sigma* ( σ^{*} ) or sigma ( σ ) to pi* ( π^{*} ) overlapping.

• Requires both filled and vacant orbitals.
• σ and π orbitals often participate in these interactions.
• Correct overlap is needed for proper bond formation.

Clear understanding of orbital overlapping aids in visualizing chemical bonds and interactions.

Sigma Bond Formation

Sigma ( σ ) bond formation occurs when two orbitals overlap head-on. This results in a strong and stable bond. In hydrolysis reactions involving compounds like methyl chloride, sigma bonds are formed through orbital overlapping.
The nucleophile's filled orbital overlaps with the vacant site on the electrophile, creating or breaking sigma bonds. For example, in the hydrolysis of methyl chloride, the attack may lead to breaking an existing bond and forming a new σ bond with the nucleophile.

• Formed through head-on overlapping of orbitals.
• Stronger than pi ( π ) bonds.
• Common in simple organic and inorganic molecules.

A solid grasp of sigma bond formation provides insight into the stability and reactivity of molecules.