Question

1. The electronic configuration of some elements
are given below:
(i) 1s2 2s2 2p4
(i) 1s2 2s 2p 3s!
(ii) 192 2s2 2p 3s2 3p 4.s2
(iv) 152 2s22p
(V)
1s 2s 2p 3s 3p?
(vi) 1s 2s 2p3
(vii) 152 252 2p 3s 3p 452 305
(viii) 152 252 2p 3s 3p5
Name these element and indicate which of them
is (a) an alkali metal, (b) an alkaline earth metal,
(c) a halogen, (d) a noble gas, (e) belongs to group
15, (1) belong to second period, (g) has lowest
chemical reactivity, (h) belongs to p-block
elements and (i) is a transition element.
Praha​

Answer 1

Answer:

The first element A, has 2 electrons in it's outermost shell, thus it valency is 2.

The second element B, has 7 electrons in it's outermost shell, thus it's valency is 1.

Thus theformula of the ionic compound formed by these atoms is AB2.

Hope this helps, inform if wrong.

Btw, the elements are Mg and F respectively.