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Question
Which of the following statements are true for pure substances?
(i) Pure substances contain only one kind of particles
(ii) Pure substances may be compounds or mixtures
(iii) Pure substances have the same composition throughout
(iv) Pure substances can be exemplified by all elements other than nickel
Options
(i) and (ii)
(i) and (iii)
(iii) and (iv)
(ii) and (iii)
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Solution
(i) and (iii)
Explanation:
Pure substances are made up of only one kind of particle and they have the same composition throughout. Mixtures are not pure substances. Only elements and compounds are pure substances.
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