Question

dry powder extinguishers contains

Answer 1

different propellants are used. With dry chemical extinguishers, nitrogen is typically used; water and foam extinguishers typically use air.

Answer 2

It contains dry chemicals like mono ammonium phospate and potassium bicarbonate and sodium bicarbonate. wet chemicals like potassium acetate and soapy foam.
water and carbon dioxideand halon or halotron is used which is eco friendly.
powdered copper , aluminium, lithium , magnesium ,potassium.