It is possible to determine the ionization energy for hydrogen using the Bohr equation.Calculate the ionization energy (in kJ)for a mole of hydrogen atoms,making the assumption that ionization is the transition from A) 7.62 × 10³ kJ B) 2.76 × 10³ kJ C) 1.31 × 10³ kJ D) 3.62 × 10³ kJ E) 5.33 × 10³ kJ

Question

Quizplus · Accepted Answer

According to the Bohr equation,
E = - R_H*(1/n^2)
where E is the energy of the transition, R_H is the Rydberg constant for hydrogen, and n is the initial energy level of the electron.
For ionization, n=1 (since the electron is completely removed from the atom). Therefore,
E = - R_H*(1/1^2) = - R_H
The ionization energy is the positive of this value, so it is R_H.
Using the value of R_H = 2.18 × 10^-18 J, we can convert to kJ/mol:
R_H = (2.18 × 10^-18 J)/(1000 J/kJ)*(6.022 × 10^23 atoms/mol) 
= 1.31 × 10^2 kJ/mol
Therefore, the ionization energy for a mole of hydrogen atoms is 1.31 × 10^2 kJ/mol, which is answer choice C.

It Is Possible to Determine the Ionization Energy for Hydrogen