a) What would happen if sodium and potassium are kept in open air? [2 MARKS]
b) Which gas is used for extinguishing flames? How does it work? [3 MARKS]
a) What would happen if sodium and potassium are kept in open air? [2 MARKS]
b) Which gas is used for extinguishing flames? How does it work? [3 MARKS]
a) 2 Marks
b) 3 Marks
a) Both sodium and potassium are highly reactive metals. They react violently (may catch fire) with oxygen and moisture present in air even at the room temperature. A lot of heat is evolved when such reaction occurs and as such the metal is lost because it makes oxides. Hence, these extremely reactive metals are not kept in open but are kept immersed in the kerosene to keep them from reacting.
b) Carbon dioxide is the gas which is used for extinguishing flames.
Carbon dioxide is a non-supporter of combustion and hence does not support burning. On the other hand, it is heavier than oxygen because of which it displaces oxygen and cuts off the supply of the fuel.
a) 2 Marks
b) 3 Marks
a) Both sodium and potassium are highly reactive metals. They react violently (may catch fire) with oxygen and moisture present in air even at the room temperature. A lot of heat is evolved when such reaction occurs and as such the metal is lost because it makes oxides. Hence, these extremely reactive metals are not kept in open but are kept immersed in the kerosene to keep them from reacting.
b) Carbon dioxide is the gas which is used for extinguishing flames.
Carbon dioxide is a non-supporter of combustion and hence does not support burning. On the other hand, it is heavier than oxygen because of which it displaces oxygen and cuts off the supply of the fuel.
