Question

Supposing the ionisation energy of hydrogen like species is 960 eV. Find out the value of principal quantum number having the energy equal to - 60 eV.

• A. n = 2
• B. n = 3
• C. n = 4
• D. n = 5

Answer 1

The correct option is C n = 4

As we know,

$En=\frac{E_1}{n^2}\times Z^{2}I.P=-E_1$

$-60eV=-\frac{960}{n^2}$ $n^2=\frac{96}{6}=\frac{32}{2}=16$

n = 4