Question

If p and q are third period elements in the periodic table but p loses two electrons whereas q gains one electron to form a molecule of pq square. Write the name and molecular formula of the molecule. Also write the valency of element p and q.

Answer 1

Answer:

name of molecule: magnesium chloride

molecular formula: MgCl2

valence element p: 2

valence of element q: 7

Explanation:

p loses two electrons this means that it is a group two element ( alkaline earth metal). these elements have two electrons in the outer most energy level which accounts to electron valence 2. group two elements have low electronegativity hence easily lose two electrons in chemical reactions.

element q gains one electron. this means that they have very high electronegativity hence accept electrons in their outer most energy level to obtain its octet value. basicaly it has 7 electrons in the outer enegy level hence its valence is 7.

Mg(s) + Cl2 (g) = MgCl2 (s)