Question

The energy of an electron in the first Bohr orbit of H - atom is - 13.6 eV. Then, which of the following statement(s) is/are correct for $H{e}^{+}$ ?

• A. The energy of electron in second Bohr orbit is -13.6eV
• B. The kinetic energy of electron in the first orbit is 54.46 eV
• C. The kinetic energy of electron in the second orbit is 13.6 eV
• D. The speed of electron in the second orbit is $2.19\times {10}^{6}m{s}^1$

Answer 1

Answer: (A), (B), (C), (D)

The speed of electron in the second orbit is $2.19\times {10}^{6}m{s}^1$

$E_n=-13.6\frac{Z^2}{n^2};forH{e}^{+},Z=2$
$K.E.=-E_n=13.6\frac{x^2}{n^2}$;
$v_n=2.19\times {10}^{6}Z/nm{s}^{-1}$