Question

The atomic number of an element X is 19 ( Symbol is not real)

a. Write the subshell electronic configuration of the element X

b. Which block of the periodic table does it belong

c. Find the group number and period number

d. Write the chemical formula of the oxide of element X (Oxidation number of O is -2)​

Answer 1

a) Configuration of X(19)=2,8,8,1.

b) It belongs to fourth period and its valency is 1.

c) Basic oxide (X2O)

d) X2 O+H2 O→2XOH

Answer 2

Answer:

a) K shell: 2

   L shell: 8

   M shell: 8

   N shell: 1

b) Block s

c) 1st group 4th period

d) K + O2 = K2O