The total number of orbitals associated with the principal quantum number $n = 5$ is

For a given value of quantum number $l$,the number of allowed values of $m$ is given by

Using $s$,$p$,$d$,and $f$ notations,describe the orbital with the following quantum numbers:
$(a)$ $n=1$,$l=0$
$(b)$ $n=3$,$l=1$
$(c)$ $n=4$,$l=2$
$(d)$ $n=4$,$l=3$

Identify the correct statements:
a) In an atom,the maximum number of electrons with $n=4$ and $m_s=+\frac{1}{2}$ is $16$.
b) There are $4$ subshells associated with $n=5$.
c) $n=2, l=1, m_l=0$ and $m_s=-\frac{1}{2}$ is a possible set of quantum numbers.
d) The number of radial nodes for $3s$ orbital is $2$.

Which orbital is closer to the nucleus: $2p$ or $3p$?

If the electronic configuration of a nitrogen atom were $1s^7$,its energy would be lower than the ground state configuration $1s^2 2s^2 2p^3$ because the electrons would be closer to the nucleus. However,the configuration $1s^7$ is not observed. Which of the following principles is violated?