Question

Example 2: Calculate the energy (in eV) associated with the electron revolving in the 4ch orbit of a single electron species with atomic number 3.
​

Answer 1

Explanation:

Energy of electron in nth state of hydrogen atom E

n

=

n

2

−13.6

eV

Thus energy of electron revolving in third (n=3) orbit, E

3

=

3

2

−13.6

eV

⟹ E

3

=−1.51 eV

Answer 2

Explanation:

ΔE=13.6eV×z  

2

×(1/2  

2

−1/3  

2

)

According to question, ΔE=47.2eV

47.2eV=1.89eV×z  

2

 

⇒z  

2

=25

⇒z=5.