IUPAC name of diethyl ether is:(A)- Ethoxy ether(B)- diethyl ether(C)- ethoxyethane (D)- none of these

To determine the IUPAC name of diethyl ether, let’s break down the options:

Diethyl ether: This is the common name for the compound, but it is not the IUPAC name.

Ethoxy ether: This is also a common name, but not the IUPAC name.

Ethoxyethane: In this name, "ethoxy-" is a substituent group, and "ethane" is the parent chain. This is the correct IUPAC name for diethyl ether.

None of these: This option would only be correct if none of the given names were accurate.

Explanation:
Diethyl ether consists of two ethyl groups (ethyl groups are -C₂H₅) connected by an oxygen atom. In IUPAC nomenclature, the structure is named as an alkyl ether where the smaller alkyl group is named as an "alkoxy" group and the larger alkyl group forms the base name.

So for diethyl ether:

The two ethyl groups are both attached to an oxygen atom.
In the IUPAC system, this is named "ethoxyethane," where "ethoxy-" refers to the ethyl group attached via an oxygen, and "ethane" refers to the base structure.
Thus, the IUPAC name of diethyl ether is (C) ethoxyethane.