Why is dry ice solid at room temperature whereas CO2 is gas?

I think that it would help to describe convection. Air that is really cold doesn't move much on its own. When dry ice heats up it creates a layer of really cold air that stays in place around it unless some other force acts to push it away. read more

At room temperature, the pressure on the CO2 would have to be greater than 5.11 atm--so it doesn't happen under normal conditions. Looking at the phase diagram shows you why solid dry ice sublimes (goes directly from solid to gas without becoming a liquid). read more

Only very weak dispersion intermolecular forces hold the molecules together and CO2is a gas at room temperature. SiO2 is a network covalent solid. Each silicon makes four bonds by making four Si-O single bonds. read more