Question

17. The electrons in the atoms of four elements A, B, C and D are distributed in threeshells
having 1, 3, 5 and 7 electrons respectively in their outermost shells. Write thegroup
numbers in which these elements are placed in the Modern Periodic Table.Write the
electronic configuration of the atoms of B and D and the molecular formulaof the
compound formed when B and D combine​

Answer 1

Answer:

7

Explanation: 2+2 = 5