One kilogram of ice at the freezing point (0°C) has a thermal energy of 1.14 MJ (million joules), while one kilogram of liquid water at the same temperature has 1.48 MJ—more energy! Likewise, one kilogram of water at the boiling point (100°C) has 1.90 MJ of thermal energy, while one kilogram of steam at the same temperature has 4.15 MJ. How can gas molecules contain more thermal energy than liquid molecules at the same temperature? The answer is that a significant amount of energy had to be added to the ice to cause it to change phase to water, and much more energy had to be added to the water in order for it to change phase from liquid to steam. The added energy breaks the intermolecular bonds among the molecules. The higher energy per unit mass for steam compared to boiling water is why steam burns are so dangerous.
When water changes from a liquid to a solid, does this require energy or release energy?
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Water has more energy than ice, so when it freezes, it releases energy. 
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Every day you encounter matter in one of its three phases: the floor you walk on is matter in its solid state; the water you drink during the day is in its liquid state; and the air you breathe is in its gaseous state. Each of these three phases of matter has unique characteristics. Matter in its solid state holds its shape. A liquid can change its shape by flowing to fill its container, but liquids keep their volumes constant. A gas takes the shape of its container by expanding (or contracting) its volume.
We learn from childhood about the three phases of matter: solid, liquid, and gas. But did you know there's a fourth? It's called a plasma, which occurs when a gas is at a temperature high enough that some (or all) of the electrons break free from their atoms or molecules. Speeding around in a plasma are both free electrons (negatively-charged) and the rest of the atoms (the positively-charged ion). Plasma is a good conductor of electricity, can block some wavelengths of light, and, because it is comprised of charged particles, can be manipulated by both electric and magnetic fields.