scienceOnline version states of matter by Thinyane Makoti 1 sublimation occurs when a ice melts to form liquid water b water boils to form water vapor c gaseous carbon dioxide forms dry ice 2 The melting point of water is 0°c. Its freezing point is a 100°c b 0°c c 50°c 3 Name the process that best describes the direct change of a solid to a gas a melting b evaporation c sublimation 4 In a gas, particles are a closely packed in a regular pattern b moving freely and close to one another c colliding and bouncing in vaious directions 5 When water vapor cools down it is a vaporizing b condensing c melting d solidifying