An inorganic compound $(A)$ made of two most occurring elements in the Earth's crust and used in building…
An inorganic compound $(A)$ made of two most occurring elements in the Earth's crust and used in building construction, when made to react with carbon, forms a poisonous gas $(B)$ which is most stable diatomic molecule, compound $(A)$ and $(B)$ are
$\mathrm{SiO}_2, \mathrm{CO}_2$
$\mathrm{SiO}_2, \mathrm{CO}$
$\mathrm{SiO}_2, \mathrm{~N}_2$
$\mathrm{CaO}, \mathrm{CO}_2$
Solution
Silicon ( $\mathrm{Si}$ ) and oxygen $(\mathrm{O})$ both are present in Earth's crust and used in construction (in the form of $\mathrm{SiO}_2$ ).
$\mathrm{SiO}_2(A)$ i.e. silicon dioxide is used in the building construction to produce concrete. In its crystalline form it is used in hydraulic fracturing.
When $\mathrm{SiO}_2$ react with carbon, it will form $\mathrm{CO}$ and silicon, it is called a displacement reaction because carbon is more reactive, than silicon. As a result $\mathrm{CO}$, a poisonous diatomic gas formed.
