Question

15. The electronic configuration of an element is y, y.
2y. The number of valence electrons in it will be
(1) 2
(2) 1
(3) 4
(4) 3
16. The polyatomic ion containing five atoms is
(1) Phosphate ion (2) Carbonate ion
(3) Sulphite ion (4) Nitrate ion
17. The correct chemical formula of aluminium
sulphate is
(1) Al(SO4)2 (2) Al(SO4)3
(3) Al2(SO4)3 (4) Al_(SO3)2​

Answer 1

Answer:

a)2

b)2

3)4......thanku

Answer 2

Answer:

17 q..ans is (2)

hope it may help

i am sry for not answering the rest