A lithium atom has three electrons. Assume the following simple picture of the atom. Two electrons m — Atomic Structure Chemistry Question
Question
A lithium atom has three electrons. Assume the following simple picture of the atom. Two electrons move close to the nucleus making up a spherical cloud around it and the third moves outside this cloud in a circular orbit. Bohr's model can be used for the motion of this third electron but $n = 1$ state is not available to it. The ionization energy of lithium in ground state, using the above picture, is
Answer: C
💡 Solution & Explanation
The third electron experiences an effective nuclear charge $Z_{eff} = +1$ (since $+3$ nucleus is shielded by two inner electrons). For this electron, the available ground state is $n=2$. $I.E. = 13.6 \times \frac{Z_{eff}^2}{n^2} = 13.6 \times \frac{1^2}{2^2} = 3.4$ eV. Therefore, correct answer is C.
💬Ask on WhatsApp →
Still have doubts about this question?
Send it to our AI chemistry tutor on WhatsApp — gets answered in minutes