An electron in a Bohr hydrogen atom has an energy of -1.362 × 10-19 J. The value of n for this electron is ________.

Question

An electron in a Bohr hydrogen atom has an energy of -1.362 × 10-19 J. The value of n for this electron is ________.

Answer 1

The energy for the nth energy level of a hydrogen atom is given by the equation

E_n = -2.178 x 10^-18 J / n².  Rearranging the equation and substituting the given energy,  n² = -2.178 x 10^-18 J / -1.362 x 10^-19 J = 16.  Therefore, n is 4.