Question
Explain ground state and ionisation energy of hydrogen atom.
✓
Answer
$\rightarrow$ The energy of an atom is the least when its electron is revolving in an orbit closest to the nucleus i.e., for $n=1$.
$\rightarrow$ As the value of $n$ increases, the energy of the electron also increases.
$\rightarrow$ The lowest state of the atom is called the ground state, is that of lowest energy, with the electron revolving in the orbit of smallest radius, the Bohr radius $\left(a_0\right)$.
The energy of this state
$E _n=-\frac{13.6}{n^2} e V$
$n=1$
$E _1=-13.6 eV$
$\rightarrow$ Therefore, the minimum energy required to free the electron from the ground state of the hydrogen atom is $13.6 eV$ . It is called the ionisation energy of a the hydrogen atom.
$\rightarrow$ As the value of $n$ increases, the energy of the electron also increases.
$\rightarrow$ The lowest state of the atom is called the ground state, is that of lowest energy, with the electron revolving in the orbit of smallest radius, the Bohr radius $\left(a_0\right)$.
The energy of this state
$E _n=-\frac{13.6}{n^2} e V$
$n=1$
$E _1=-13.6 eV$
$\rightarrow$ Therefore, the minimum energy required to free the electron from the ground state of the hydrogen atom is $13.6 eV$ . It is called the ionisation energy of a the hydrogen atom.
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