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Which one of the following statements about a compound is NOT correct?

Options

  1. AA compound is a substance composed of two or more elements, chemically combined in a fixed proportion
  2. BProperties of a compound are different from its constituent elements
  3. CA compound is an impure substance
  4. DThe constituents of a compound can be separated only by chemical or electrochemical reactions

Correct answer

C. A compound is an impure substance

Step-by-step solution

A compound is a pure substance because it consists of molecules of only one kind, which are formed by the chemical combination of two or more elements in a fixed ratio by mass. The properties of a compound are entirely different from those of its constituent elements. The constituents of a compound cannot be separated by physical methods but can be separated by chemical or electrochemical methods. Therefore, the statement that a compound is an impure substance is incorrect. Answer: A compound is an impure substance

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