Question

How is chemical communication beneficial for transmitting information or signal as compare to Electrical signal

Answer 1

The chemical communication is beneficial for transmitting information since through this method, a chemical compound will be released from the various glands, which will diffuse all around the original cell. If other cells around have means to detect this compound, using special molecules on their surfaces, then they would be able to recognise information, and even transmit it. 
Electrical impulses can only reach those cells that are connected by nervous tissue. The cell transmitting would also need to reset its mechanism. In these cases, chemical communication is more beneficial.