Question

An element of group $14$ forms two oxides one of which is highly poisonous and neutral. Other oxide can be easily liquefied and compressed to give a solid which is used as a refrigerant under the name of drikold. The element and the oxides are

• A. $Si, SiO, SiO_{2}$
• B. $Pb,PbO,PbO_{2}$
• C. $C, CO, CO_{2}$
• D. $Sn, SnO, SnO_{ 2}$

Answer 1

Answer: (C)

$C, CO, CO_{2}$

Answer 2

$C$ forms two oxides $CO$ and $CO_{2}. CO$ is neutral and poisonous. $CO_{2}$ can be compressed to a refrigerant dry ice or solid $CO_{2}. SiO$ is unstable. $SnO$ and $PbO$ are amphoteric in nature.