SSC
CHEMISTRY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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A substance does not have a fixed composition.
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Always True
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Sometimes True
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Never True
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None of the above
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Explanation:
Detailed explanation-1: -Pure substances are heterogeneous . A pure substance is homogeneous but does not have a fixed composition.
Detailed explanation-2: -A pure substance always has a definite and constant composition. A mixture is a physical combination of two or more pure substances in which each substance retains its own chemical identity.
Detailed explanation-3: -Reason: Pure substances are the substances which have fixed composition and does not contain any impurities.
Detailed explanation-4: -Elements react to form new compounds. The composition of each new substance is always fixed. The new substance has totally different properties. The constituents can be separated only by chemical or electrochemical reactions.
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