Which of the following is recommended for extinguishing or controlling the spread of alkali metal fires

Dry Chemical

Explanation:

The answer choices for this question are:

Dry-Chemical Carbon Dioxide Oxygen

Solution

Alkali metals, like lithium, sodium and potassium, react violently with water, and must be kept in a dry atmosphere to avoid explosion and fire.

There is a specific norm from the National Fire Protection Association, Inc, named NFPA 484 Standard for Combustible Metals, Metal Powders, and Metal Dusts and a chapter for LIthium where it states the use of Class D extinguishing agents.

Class D fire extinguisher is Dry Powder extinguisher.

Carbon dioxide is not suitable for extinguishing or controlling the spread of alkali metal fires because they can react and increase the fire or spread the metal dust.

Oxygen, of course, is not a fire extinguisher agent, on the contrary it is a essential component of fire: the ost basic principle to extinguish fires is to to remove the oxygen around the fire.