Solved UPSC CDS/OTA Question
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Q · Mixtures and CompoundsMedium · 45s
Which of the following is true about pure substances? 1. They cannot be separated by physical methods. 2. They have a fixed composition. Select correct:
TopicMixtures and Compounds
Question Typemultiple choice
DifficultyMedium
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
The complete worked solution.
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Pure substances (elements, compounds) have a definite composition and need chemical methods for decomposition.
Final Answer: Option C — Both 1 and 2