What are the types of solutions?

Solutions can be classified in several different types based on different criteria. 

Based on quantity of solute in the solution a solution may be classified as: 

• Unsaturated Solution – More solute can be dissolved in the solvent at a given temperature
• Saturated Solution – No more solute can be dissolved in the solvent at a given temperature
• Supersaturated Solution – More solute can be dissolved in the solvent by increasing the temperature or pressure, resulting in crystal formation

Based on the amount of solvent added, a solution may be classified as: 

• Dilute Solution – A small amount of solute is dissolved in a large quantity of solvent
• Concentrated Solution – A large amount of solute is dissolved in a smaller quantity of solvent

Based on the physical state of the solute and the solvent, a solution may be classified as: 

• Solid-solid – alloys such as brass and bronze
• Solid-liquid – salt water and sugar water
• Liquid-solid – mercury in amalgamated zinc
• Liquid-liquid – alcohol in water 
• Solid-gas – sublimation of substances such as camphor into the air
• Gas-solid – hydrogen absorbed in palladium
• Liquid-gas – aerosol or water vapor in the air
• Gas-liquid – aerated drinks made from carbon mixed in water 
• Gas-gas – mixture of gases in the air