Carbon dioxide is a gas at room temperature & silicon(IV) oxide is a solid with a high melting point. Explain, these observations in terms of ..the...

The carbon dioxide molecule is a molecule that is
perfectly symmetric about its axes.  There is a carbon atom in the center with oxygen
atoms at either side.  It has no dipole moment so it electrically neutral.  It does not
bond easily with other CO2 molecules hence it is a gas.  Silicon dioxide molecules tend
to link up into tetrahedral structures with oxygen atoms linking up neighboring silicon
atoms.  This produces a strong crystal structure that repeats
endlessly.