Which gas is released when $Na_2CO_3$ is heated?

The solution of sodium metal in liquid ammonia is a strong reducing agent due to the presence of:

$(a)$ Describe the chemical properties of alkali metals with air,water,dihydrogen,and halogens.
$(b)$ Explain the reduction potential of alkali metal elements.
$(c)$ Which type of solutions are formed on the reaction of alkali metals with liquid ammonia?

Mercury is transported in containers made of

What is produced when $Mg$ burns in $CO_2$?

$KO_2$ (Potassium superoxide) is used in confined spaces and submarines because it