Question

Write the electronic configuration of two elements A and B whose atomic numbers are 20 and 17 respectively. Write the molecular formula of the compound formed when element A reacts with element B. State whether this compound is acidic, basic or neutral. Give a reason to justify your answer.

Answer 1

The electronic configuration of element A whose atomic number is 20 is 2,8,8,2 and ​the electronic configuration of element B whose atomic number is 17 is 2,8,7. The molecular formula of the compound formed when element A reacts with element B is AB₂. The given compound is CaCl₂ formed by the reaction of Ca(OH)₂ (strong base) and HCl (strong acid). Since the reaction between a strong acid and a strong base yields a neutral salt so, CaCl₂ is neutral.