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प्रश्न
Cement, the important building material is a mixture of oxides of several elements. Besides calcium, iron and sulphur, oxides of elements of which of the group (s) are present in the mixture?
विकल्प
Group 2
Groups 2, 13 and 14
Groups 2 and 13
Groups 2 and 14
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उत्तर
Groups 2, 13 and 14
Explanation:
Cement contains elements of group 2 (Ca), group 13 (Al) and group 14 (Si).
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