Question

water is called as water vapour in gaseous state but co2 is called as a gas why?

Answer 1

Water exist in liquid state and the molecules of water after gaining sufficient energy come into gaseous or the vapour phase, however, carbon-di-oxide molecules naturally exist in the gaseous state and are not formed by vapourization of liquid carbon-di-oxide (which does not exist as carbon-di-oxide gets deposited as solid upon cooling or applying pressure) as . Water vapours on the other hand are formed by phase change of water from liquid to gas. Therefore water in gaseous form is known as water vapour and not gas.