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Question
Which of the following substances will precipitate the negatively charged emulsions?
(i) \[\ce{KCl}\]
(ii) glucose
(iii) urea
(iv) \[\ce{NaCl}\]
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Solution
(i) \[\ce{KCl}\]
(iv) \[\ce{NaCl}\]
Explanation:
Negatively charged emulsion can be precipitated by oppositely charged electrolyte. \[\ce{Na+}\] and \[\ce{K+}\] from the electrolyte can neutralize the negatively charge emulsion and precipitate the colloid.
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