I have done the question but it seems wrong.

**Q- Using the Rydberg equation calculate the ionisation energy of an electron in the 4s orbital of hydrogen.**

Ok first of all since its hydrogen I should use Rh right? So Rh= **2.18x10^-18**

Now since its asking for ionization energy the first n1 value is **1**

And the second n2 value im saying is **4**, as its in the **4s** orbital. Im not sure??

So putting this together is **2.18x10^-18** X (**1/1^2** – **¼^2**)

So... **2.18x10^-18** X 0.1875 = **4.08x10^-19**

Now i got the frequency, Now to work out Ionization energy I obviously use **E=hv** where **h=6.626x10^-34**

So now** 4.08x10^-19** X ** 6.626x10^-34** = **2.70x10^-52 !!!!**

Is that correct? The number is incredibly small? And I don’t know whether this is the correct way of working it out for the 4s orbital , or weather all the values I have inputted are correct. I would appreciate it so much for some help