Question

Holme's signal can be given by using:

Answer 1

Holme's signal is the containers containing calcium carbide and calcium phosphide gas. The Holme's signal is a method used by sailors for creating emergency lighting on the sea surface during the night. It was used as a technique to guide the ships in the sea where no light sources are available.
Holme's signal can be given by $Ca{C}_2+C{a}_3{P}_2$

$C{a}_3{P}_2+6H_{2}O\to 2P{H}_3\uparrow +3Ca(OH{)}_2$
$Ca{C}_2+2H_{2}O\to C_2{H}_2\uparrow +Ca(OH{)}_2$