Question

An elementahas atomic number 11 and another element b has atomic number 8.a and b combine to form an ionic compound. what would be the formula of compound formed?

Answer 1

element a has 11 protons
electronic configuration=2,8,1
its valency=1

element b has 8 protons
electronic configuration=2,6
its valency=2

therefore by criss cross method

A B
1 2

formula of compound is A2B

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