Answer: options a, c, d and e
a. The electron configuration of O2− is [He]2s2 2p6.
c. The electron configuration of Ni is [Ar]4s2 3d8.
d. The electron configuration of K is [Ar]4s0 3d1.
e. The electron configuration of Si is [Ne]3s2 3p2.
Explanation:
A) The electronic configuration of Oxygen (O2) = [He] 2s2 2p4. On receiving TWO electrons, it becomes O2- with a new electronic configuration of [He] 2s2 2p6.
C) The electronic configuration of NICKEL (Ni) = [Ar], 3d8, 4s2.
Atomic Number of Nickel (Ni ) = 28. Electronic configuration in full is 1s2, 2s2, 2p6, 3s2 3p6 3d8, 4s2
D) The electronic configuration of Potassium (K) = [Ar] 4s1.
Atomic number of K = 19.
Electronic configuration in full is 1s2, 2s2, 2p6, 3s2 3p6 4s1.
E) The electron configuration of Si = [Ne] 3s23p2. Atomic number of Si = 14.
Electronic configuration in full is 1s2, 2s2, 2p6, 3s2 3p2
NOTE:
Atomic number of Silver (Ag) = 47.
Its electronic configuration is [Kr] 4d10 5s1.
On giving out ONE electron, it becomes Ag+ with [Kr] 4d10. Thus, ONLY Option b is INCORRECT.
