The correct answer is $(1), (B), (E)$ only.
Statement $(A)$ is incorrect. Alkyl halides are polar, but they are not soluble in water because water is a polar solvent and alkyl halides are nonpolar solvents.
Statement $(B)$ is correct. Alkyl halides, on reaction with alcoholic $KOH$, give alkenes. This is known as the Williamson ether synthesis reaction.
Statement $(C)$ is incorrect. Alkyl halides, on reaction with $AgNO_2$, give $RONO_2$, which is an alkyl nitrite.
Statement $(D)$ is correct. $SN1$ reactions proceed with the inversion of configuration. This is because the nucleophile attacks the carbocation from the opposite side of where the leaving group left.
Statement $(E)$ is correct. Alkyl halides have higher boiling points than their parent alkanes because of the strong intermolecular dipole-dipole interactions.
Therefore, the correct answer is $(1), (B), (E)$ only.
Additional Information:
Alkyl halides are organic compounds in which a halogen atom (\(F, Cl, Br, \text{ or } I\)) is bonded to a carbon atom. They are generally prepared by the halogenation of alkanes.
Alkyl halides are polar compounds, but they are not soluble in water because water is a polar solvent and alkyl halides are nonpolar solvents. This is because the halogen atom is more electronegative than the carbon atom, so it pulls the electrons towards itself, creating a partial positive charge on the carbon atom (\(C^{\delta^+\})) and a partial negative charge on the halogen atom (\(X^{\delta^-\})). However, the alkyl halide molecule as a whole is still nonpolar because the partial charges are evenly distributed throughout the molecule.
Alkyl halides can react with a variety of other compounds, including alcohols, metals, and nucleophiles. One important reaction of alkyl halides is the Williamson ether synthesis reaction, which is used to prepare ethers. In this reaction, an alkyl halide reacts with an alkoxide ion \((R'O^-)\) to give an ether. The reaction is shown below:
\[RX + R'O^- \rightarrow ROR' + X^-\]
Another important reaction of alkyl halides is the \(S_N1\) reaction, which is a nucleophilic substitution reaction. In this reaction, a nucleophile (\(Nu^-\)) attacks the carbocation (\(R^+\)) formed by the ionization of the alkyl halide. The reaction is shown below:
\[RX \rightarrow R^+ + X^-\]
\[R^+ + Nu^- \rightarrow RNu\]
The \(S_N1\) reaction proceeds with inversion of configuration, meaning that the nucleophile attacks the carbocation from the opposite side of where the leaving group (\(X^-\)) left. This is because the carbocation is a planar intermediate, so the nucleophile can attack from either side.
Alkyl halides have higher boiling points than their parent alkanes because of the strong intermolecular dipole-dipole interactions. The halogen atom is more electronegative than the carbon atom, so it pulls the electrons towards itself, creating a partial positive charge on the carbon atom (\(C\delta^+\)) and a partial negative charge on the halogen atom (\(X\delta^-\)). This results in strong dipole-dipole interactions between the alkyl halide molecules, which raises the boiling point.
Here are some examples of alkyl halide reactions:
1. Alkyl halides + alcoholic KOH \(\rightarrow\) alkenes (Williamson ether synthesis reaction)
\[CH_3CH_2Cl + KOH (\text{in ethanol}) \rightarrow CH_3CH_2O + KCl\]
2. Alkyl halides + metals \(\rightarrow\) metal halides + alkanes
\[2 CH_3Cl + 2 Na \rightarrow 2 NaCl + CH_3CH_3\]
3. Alkyl halides + nucleophiles \(\rightarrow\) alkyl nucleophiles (\(SN1\) reaction)
\[CH_3Br + H_2O \rightarrow CH_3OH + HBr\]
Alkyl halides are widely used in organic synthesis because they are versatile reagents that can be used to prepare a variety of other organic compounds. |
