Air is a combination of various gases like nitrogen, oxygen, argon, carbon dioxide, and trace amounts of others. Since these gases are not chemically bonded together and retain their individual properties, air is considered a mixture. The composition of air can vary, especially with pollution, but it remains a mixture regardless of the presence or absence of pollutants. A compound is formed when two or more elements are chemically bonded in a fixed ratio.
Air is— [A] always a compound [B] always a mixture [C] a compound in pollution free zones [D] a mixture in industrial zones
Asked in HORTICULTURE DEVELOPMENT OF‐ FICER(HDO) 2015 · Topic: Physical and Chemical Changes, Solution (Concept of Solutions: Solute, Solvent, and Components)
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Answer: B. [B] always a mixture
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