Question

What does the symbol "E3" represent?

Answer 1

I believe that the answer is B.

Answer 2

Answer: The energy of the electron in third energy level.

Explanation: The energy of the electrons depend on the value of n, i.e the value of principal quantum number which tells the shell of the electron.

$E=\frac{-13.6Z^2}{n^2}$

E= energy

Z= atomic number

n= principal quantum number

Thus $E_3$ represents the energy of the electron which is present in n=3.