Question

Which of the following statements about electronic configurations of atoms and mononuclear ions, and atomic orbital quantum numbers, are true or false.

true false  The principle quantum number can have any positive integer value.
true false  The value of m_l is always less than or equal to l (for a given orbital).
true false  The valence electronic configuration of phosphorus is 3s²3p³.
true false  Fe³⁺ has the same electronic configuration as V.
true false  The electronic configuration of the hydride anion is 1s²

Answer 1

1. The principle quantum number can take any positive integral values as 1,2,3,4... so it's True.

2. The value of ml always lies within (-l to l) hence any value of ml will be either less or equal to l so, it's True.

3. The whole configuration can be written as 1s2 2s2 2p6 3s2 3p3 hence the statement is True.

4.  Fe3+ is [Ar] 3d5 because half filled orbitals are more stable whereas V is [Ar] 3d3 4s2 so they are different. Hence it's False.

5.  Hydride ion has 2 electrons so simply the configuration will be 1s2 hence it's also True.