Class 10 Chemistry Water Full Notes Punjab Curriculum

Water MCQ`s ,Short Questions and Long Questions Free PDF Download Punjab Curriculum

Chemistry Chapter 15 : Water Complete Notes MCQ`s, Short Questions and Long Questions

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Key Points of Chapter 15 Water Notes

Water is an excellent solvent, has high specific heat capacity, high surface tension and high capillary action.
Water is universal solvent because of its polarity and hydrogen bonding ability.
Soft water produces lather with soap.
Hard water does not produce lather with soap.
Hardness is of two types: temporary and permanent.
Temporary hardness is because of bicarbonates of calcium and magnesium. This hardness can be removed by boiling or by addition of slaked lime (Ca(OH)2) in water.
Permanent hardness is because of presence of carbonates and sulphates of calcium and magnesium. This hardness can be removed by treating water with washing soda and sodium zeolite.
Used water is called waste water or sewage.
Water pollution is caused by affecting water quality by pollutants.
Industrial effluents are one of the main causes of water pollution. It includes high toxic organic chemicals, inorganic salts, heavy metals, mineral acids, oil and greases, etc.
Household water in the sewage from toilets, baths, kitchens, etc. consists of detergents used for
cleaning purposes. Detergent being non-biodegradable causes rapid growth of aquatic plants.When these plants die and decay, they consume O2 present in the water. Thus, aquatic life is badly affected because of scarcity of O2.
Agricultural effluents consist of fertilizers and pesticides. These substances provide nitrate and phosphate ions for rapid growth of aquatic plants. When these plants die and decay, their decomposition process consumes O2 of water. Thus, depletion of O2 causes damage to the aquatic life.
Waterborne diseases are those diseases that spread because of drinking polluted water. These diseases spread because of lack of proper sanitation arrangements. These diseases can be prevented by using safe water, properly disposing sewage and controlled use of toxic chemicals