What kind of matter is fire?
It is a plasma. Technically plasma is a kind of matter.
Chemical changes in matter have the most potential danger and damage. A chemical change is a change in which one kind of matter is changed into a different type of matter. Some examples of chemical changes: the rusting of your car, setting your shoe on fire, digesting food, and the burning of magnesium metal in oxygen to form magnesium oxide.
The heat and light from fire is energy. The smoke from fire contains particles of water, gases, and the materials being burned that are matter. The flame is made up of gases like vaporized fuel, carbon dioxide, carbon monoxide, water vapor and other gases. All these are matter - occupying space and have mass.