Question

In the modern periodic table, A and B are two elements belonging to first and seventeenth group respectively and both of them belong to the third period.write their electronic configuration. which of them is a metal? why?write the chemical formula of the compound obtained when these two elements react with each other........................

Answer fast plz​

Answer 1

Answer:

first is sodium

1st group and 3rd period

general confugation-ns1

EC-1s2,2s2,2p6,3s1

second is chlorine

17th group and 3rd period

general confugation-ns2,np5

EC- 1s2,2s2,2p6,3s2,3p5

Answer 2

Answer:element a belongs to the first group so it has one electron in the valence shell.As it belongs to the third group it has three cells K,L,and M.

Since its electronic configuration is k, l, m . 2, 8, 1

element b belongs to 17th group so it has 17 electron in valence cell as it belongs to the third period it has three shells - k, l and m. Hence electronic configuration of b is k, l, that is 2,8,7.

A is a metal has it has a tendency to form electropositive ion by using its valence electron .

Explanation: