Question

Why Co2exist in the form of gas and SIO2 exist in the form of liquid

Answer 1

Carbon dioxide is simple molecular. Silicon dioxide is giant molecular.

In CO2CO2 (displayed formula: O=C=O), each molecule is attracted to other molecules due to what is called “van der Waal’s forces” or London forces. van der Waal’s forces is a very weak form of intermolecular force where temporary and induced dipoles attract one another. van der Waal’s forces are very weak and can be broken with little energy. Thus carbon dioxide melts at just over -56.6 degrees Celcius

In SiO2SiO2, every silicon atom is bonded (covalent) to four oxygen atoms. Every oxygen atom is bonded to two silicon atoms. This forms a giant, tetrahedral structure much like a diamond. All the atoms are interconnected by covalent bonds, making the lattice incredibly strong. This is proven by the fact that SiO2SiO2has a melting point of 1713 degrees Celcius (Iron melts at 1538 degrees Celcius)

Despite the fact that they are both dioxides, SiO2SiO2 is structurally closer to diamonds and CO2CO2 more similar to oxygen and nitrogen (O2O2 and N2N2 both has van der Waal’s forces) . It is all due to differences in bonding.

hope it helps.

Answer 2

there is a good Bond strength between the carbon and the oxygen due to which they undergo lateral overlapping because of this there is a weak force which is known as vanderwall force of attraction between the two molecules of carbon dioxide so they exist in the form of gas but in silicon dioxide they does not undergo in lateral overlapping so they exist in the form of liquid .