Q.Which one of the following is a simple ether ?

True — the C-O-C bond in ethers is angular (bent), not linear, so the two C-O bond dipoles do not cancel and the molecule has a net dipole moment.

In an ether, $R-O-R'$, the oxygen atom is $sp^3$ hybridised and carries two lone pairs, giving the C-O-C linkage a bent (angular) geometry (bond angle close to $110°$, similar to water) rather than a straight $180°$ line. Because the two C-O bonds are not collinear, their individual bond dipole moments do not cancel out, and ethers therefore possess a small net dipole m …

A symmetrical ether has identical alkyl/aryl groups on both sides of the oxygen; an asymmetrical (mixed) ether has two different groups. Only anisole, C6H5-O-CH3, has two different groups here.

Checking each option:

• CH3-O-CH3: two methyl groups - symmetrical.
• C2H5-O-C2H5: two ethyl groups - symmetrical. …

The compound is an ether; IUPAC names an ether as an alkoxy-substituted alkane, giving 2-methoxypropane.

The compound $CH_3$-$CH(OCH_3)$-$CH_3$ is isopropyl methyl ether. In IUPAC substitutive nomenclature, an ether $R$-$O$-$R'$ is named by treating the smaller $-OR'$ group as an alkoxy substituent on the longer alkyl chain $R$.

Here the parent chain is propane ($CH_3$-$CH_2$-$CH_3$ skeleton, 3 carbons), and the $-OCH_3$ (methoxy) group is attached at carbon 2 of that chain (the central CH). So the systematic name is 2-methoxypropane.

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Ethers are classified as simple (symmetrical) if both alkyl/aryl groups attached to the oxygen are identical, and mixed (unsymmetrical) if the two groups differ.

Checking each option:

• $C_2H_5-O-CH_3$ — ethyl and methyl groups differ → mixed ether (ethyl methyl ether).
• $C_3H_7-O-C_2H_5$ — propyl and ethyl groups differ → mixed ether. …