Question

answer it if you are a real genius

Answer 1

10A) FOR ELEMENT X

       i. Atomic number - 17

         since no. of protons = atomic number of element

      ii. Mass number - 35

         since mass number = no. of protons + no. of neutrons

                                           = 17 + 18 = 35

FOR ELEMENT Y (same explanation as above)

        i. Atomic number - 17

        ii. Mass number - 37

The atomic species are related as they have the same atomic number.

Element X and Y represent Chlorine (as Cl atomic number is 17)

10B) given, (E.C) Electronic configuration - 2,8,7

       therefore, no. of electrons = 2+8+7 = 17

        i. Atomic number = 17

       since no. of protons = no. of electrons = 17

        ii. A valence electron is the number of electrons found in the last shell of an element. The valence electron of the given element is 7

Let's check which element has the same number of valence electrons by checking E.C (electronic configuration) of each

EC of Nitrogen (N) - 2,5

EC of Fluorine (F) - 2,7

EC of Phosphorus (P) - 2,8,4

EC of Argon (Ar) - 2,8,8

So, only Fluorine (F) has the same number of valence electrons, 7

I really hope this helped you out! I spent a lot of time typing all the explanations. Stay safe and gave a nice day!