If you have liquid water H 2 O at room temperature and you wanted water vapor gas , you could use a combination of high temperatures or low pressures to solve your problem. Points of Change Phase changes happen when you reach certain special points. Sometimes a liquid wants to become a solid.
Scientists use something called a freezing point or melting point to measure the temperature at which a liquid turns into a solid. There are physical effects that can change the melting point.
Pressure is one of those effects. When the pressure surrounding a substance increases, the freezing point and other special points also go up. It is easier to keep things solid when they are under greater pressure. States of Matter Examples. A Liquid Ocean There are many liquids around you. Oceans, lakes, and rivers are good examples of liquid water H 2 O. Planetary scientists are looking for other planets that have liquid water, but planets require very specific conditions to have water as we know it.
Solids in Ceramics Ceramic bowls are a great example of a solid. Did you know that pieces of pottery make up many of the items found from ancient civilizations? Ceramic materials are usually made from soft clay that is heated up and then slowly cooled.
The clay becomes very hard because water H 2 O is removed and the chemical bonds inside the clay change. Plasmas on the Sun Plasmas are highly energized gases that have lost their electrons. Stars, including the Sun, are covered in plasma. Hydrogen H and helium He ions float around the Sun with their electrons moving freely. They are little pieces of rubber. However, the helium He inside the balloon is a gas.
Atoms and molecules in liquids and gases are bouncing and floating around, free to move where they want. The molecules in a solid are stuck in a specific structure or arrangement of atoms. The atoms still vibrate and the electrons fly around in their orbitals, but the entire atom will not change its position.
Solid Mixtures Solids can be made of many things. They can have pure elements or a variety of compounds inside. When you have a solid with more than one type of compound, it is called a mixture. Most rocks are mixtures of many different compounds. Concrete is a good example of a man-made solid mixture. Granite is a mixture you might find when you hike around a national park. Granite is made of little pieces of quartz, mica, and other particles. Burning a sugar cube is a chemical change. Fire activates a chemical reaction between sugar and oxygen.
The oxygen in the air reacts with the sugar and the chemical bonds are broken. Iron Fe rusts when it is exposed to oxygen gas in the air. You can watch the process happen over a long period of time. The molecules change their structure as the iron is oxidized , eventually becoming iron oxide Fe 2 O 3. Rusty pipes in abandoned buildings are real world examples of the oxidation process. Isomers Some chemical changes are extremely small and happen over a series of steps.
The resulting compounds might have the same number of atoms, but they will have a different structure or combination of atoms. The sugars glucose, galactose, and fructose all have six carbon atoms, twelve hydrogen atoms, and six oxygen atoms C 6 H 12 O 6. Even though they are made of the same atoms, they have very different shapes and are called isomers.
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