Most substances we meet in daily life are mixtures. When salt is added to water it dissolves, and the salt cannot be separated by filtration, because it forms a homogeneous mixture. Sand in water does not dissolve and can be separated by filtration, so it is a heterogeneous mixture. Homogeneous mixtures like salt in water are called solutions. This chapter covers the parts and types of solutions, solubility and the factors affecting it, concentration (mass and volume percentage), hydrated salts, hygroscopy and deliquescence.
1. Solutions in Day-to-Day Life
- Sea water is a naturally existing solution – a mixture of many dissolved salts.
- Air is also a solution – a mixture of gases like nitrogen, oxygen, carbon dioxide and other gases.
- Plants take solutions of nutrients from the soil for their growth.
- Most liquids in the human body, including blood, lymph and urine, are solutions.
- Drinks like fruit juice, aerated drinks, tea and coffee are solutions.
- The ability of water to form solutions is responsible for the sustenance of life.