Based on the values of $IE_1$ and $IE_2$,which of the following represents an alkali metal?

What is the definition of ionization energy for an atom?

Which of the following species has the lowest ionization potential?

The first ionization energy of boron is less than that of beryllium because

$B$ has a smaller first ionization enthalpy than $Be$. Consider the following statements:
$(I)$ It is easier to remove a $2p$ electron than a $2s$ electron.
$(II)$ The $2p$ electron of $B$ is more shielded from the nucleus by the inner core of electrons than the $2s$ electrons of $Be$.
$(III)$ The $2s$ electron has more penetration power than the $2p$ electron.
$(IV)$ The atomic radius of $B$ is more than $Be$.
(Atomic number: $B=5, Be=4$)
The correct statements are:

The correct order of second $I.E.$ of $C$,$N$,$O$,and $F$ is: