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प्रश्न
An element E reacts with water to form a solution which turns phenolphthalein solution pink. The element E is most likely to be ______.
पर्याय
S
Ca
C
Ag
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उत्तर
An element E reacts with water to form a solution which turns phenolphthalein solution pink. The element E is most likely to be Ca.
Explanation:
Phenolphthalein is a pH indicator that turns pink in basic (alkaline) solutions. Calcium (Ca) reacts with water to form calcium hydroxide [Ca(OH)2], which is a strong base. In contrast, sulphur (S) and carbon (C) are non-metals that do not form basic solutions, while silver (Ag) is unreactive and does not react with water.
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संबंधित प्रश्न
Name the following:
Metals which forms an amphoteric oxide.
A solution of _________________ in water is green in colour.
(a) CuSO4
(b) FeSO4
(c) ZnSO4
(d) Al2(SO4)3
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Na, S, C, K, H
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