Why are ARP Request packets not transmitted (i.e., not encapsulated) like IP packets? Explain your answer.

What will be an ideal response?

ARP request is needed only when the communication in the physical layer happens using hardware address in the same network segment. Logically, ARP request is used when IP address of the host being connected is unknown. Therefore, we can not send ARP request using IP packet as a IP datagram. Another reason is even if we develop an algorithm to use IP packet for ARP, it is not efficient at all, because IP header is unnecessary to get ARP reply. In short, ARP encapsulated in ethernet frame is better approach rather than in IP datagram