Chemistry
Water acts as a universal solvent because it has a unique property to dissolve various organic and inorganic compounds. Its dielectric constant is high, which is about 80 at 20°C. All this is due to its polar nature.
(a) What properties of water make it an exceptional solvent compared to other solvents like ethanol, carbon tetrachloride, benzene, etc.
(b) Explain the environmental consequences of water's "universal solvent" property, particularly regarding pollution.
Water
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Answer
(a) Water has following properties that make it an exceptional solvent :
- Water is an exceptional solvent because its molecules are polar in nature. The oxygen atom has a partial negative charge and the hydrogen atoms have partial positive charges. Due to this polarity, water molecules can attract different types of particles and help them dissolve.
- Water also has a high dielectric constant. Therefore, it reduces the electrostatic force of attraction between positive and negative ions and dissolves many inorganic compounds. Hence, water can dissolve a wide range of solids, gases and liquids, forming aqueous solutions.
(b) Water’s property of being a universal solvent also makes it easily polluted. It can dissolve or carry harmful substances such as sewage, industrial wastes, pesticides, fertilisers and toxic chemicals. As a result, water may become unsafe for drinking and can cause diseases such as diarrhoea, typhoid, cholera and dysentery. Long-term consumption of chemically polluted water may also cause toxicity, cancer or organ damage.
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