Why is SiO2 a solid whereas CO2 is a gas at room temeperature?
The main factor influencing a given compound's state is the strength of intermolecular forces - those need to be larger than the thermal energy for a compound to be solid/liquid. For CO2 the only type of interactions possible are the weak Van der Waals forces, whereas in the case of SiO2 the solid is stabilised by the presence of strong covalent linkage all throughout the crystal lattice.
WG
Related Chemistry A Level answers
All answers ▸Why is there a difference in mechanism between tertiary halogenoalkanes and primary halogenoalkanes in nucleophilic substitution?
Explain why the first ionisation energy of phosphorous is different to that of sulfur
Ethanol can be made from the reaction between ethene and water. The reaction is exothermic and occurs at a high temperature. Describe and explain the effect of raising the temperature on the rate of achievement of equilibrium and the equilibrium yield.
Describe and explain the difference in base strength between ammonia, primary aliphatic and primary aromatic amines.