What phases of matter can be combined to create a solution?
All common phases of matter can be combined to create solutions. Air is a solution of gases, mostly nitrogen and oxygen, but also carbon dioxide, hydrogen, and many others. Saline is a solution of the solid sodium chloride dissolved in liquid water. Oxygen gas is dissolved in fresh and salt bodies of water. Brass is a solution of metals, called an alloy, and is composed of two metals, copper and zinc. Isopropyl alcohol ("rubbing alcohol") is a solution composed of two liquids, isopropyl alcohol and water.