Holme's signals produce burning gases which serve as a signal to the approaching ships contains

Options

A. A mixture of `Ca_3P_2` and `CaC_2`
B. A mixture of `Ca_3P_2` and KOH
C. A mixture of `CaC_2` and KOH
D. A mixture of `Ca_3P_2,CaC_2` and KOH

Answer

A

Explanation

In contact with water a mixture of calcium phosphide and calcium carbide produce amixture of phosphine and acetylene gas. Phosphine frequently contains traces of highly inflammable disphosphine `P_2H_4` which catches fire spontaneously. This ignites acetylene which burns with aļuminous flame and thus serves as a signal to approaching ships.