Which of the following oxides reacts with both $HCl$ and $NaOH$?

In the following reaction,identify the nature of the product formed by the complete hydrolysis of the underlined atom at $R.T.$:
$\underline{C}Cl_4 + H_2O \longrightarrow \text{No reaction}$

Gas $A$ is bubbled through slaked lime when a white precipitate is formed. On prolonged bubbling,the precipitate is dissolved. On heating the resultant solution,the white precipitate reappears with the evolution of gas $B$. The gases $A$ and $B$ respectively are

Give the chemical reaction for preparing pure $CO$.

Which of the following species is not stable?

State True or False for the following statements:
$(1)$ Fullerene has $20$ rings of $6$ members and $12$ rings of $5$ members.
$(2)$ $CO$ is neutral while $CO_2$ is acidic.
$(3)$ Boron fibres are used in making light composite material for aircraft.
$(4)$ When borax is heated in a Bunsen burner flame with $CoO$ on a loop of platinum wire,a yellow coloured $Co(BO_2)_2$ bead is formed.