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प्रश्न
Metals form basic hydroxides. Which of the following metal hydroxide is the least basic?
विकल्प
Mg(OH)2
Ca(OH)2
Sr(OH)2
Ba(OH)2
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उत्तर
Mg(OH)2
Explanation:
As the ionization enthalpy increases from Mg →Ba, the M – O bond becomes weaker and weaker down the group and hence basicity increases down the group. Thus, Mg(OH)2 is least basic.
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