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An element 'X' (Atomic number=20) burns in the presence of oxygen to form a basic oxide.

Monjur Alahi

An element 'X' (Atomic number=20) burns in the presence of oxygen to form a basic oxide. 

(i) Identify the element and write its electronic configuration. 

(ii) State its group number and period number in the Modern Periodic Table. 

(iii) Write a balanced chemical equation for the reaction when this oxide is dissolved in water.


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Salim Ahmed Kawsar

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(i) X(20) ---2,8,8,2 It is calcium.

(ii) Second group, fourth period.

(iii) CaO+H2O →  Ca(OH)2

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