# Question Video: Relating the Principal Quantum Number for an Electron to How Strongly Bound It Is Physics • 9th Grade

Complete the following sentence: The higher the value of the principal quantum number for an electron, the ＿ strongly bound to the atom it is.

01:12

### Video Transcript

Complete the following sentence. The higher the value of the principal quantum number for an electron, the blank strongly bound to the atom it is. (1) Less or (2) more.

In this question, we’re being asked about electron energy levels, specifically about principal quantum numbers, which we denote with an 𝑛. Let’s remember that electrons bound to atoms occupy discrete energy levels and emit a photon when they transition from a higher energy level to a lower energy level.

The energy level of an electron is denoted by the principal quantum number 𝑛, with 𝑛 equals one being the lowest energy level. This level is called the ground state and contains the most strongly bound electrons. As 𝑛 increases, the energy level of the electron increases and the electron moves further away from the nucleus. The strength of the bond holding the electron to the atom decreases as less additional energy is needed for the electron to escape the pull of the nucleus and become free.

So now we can complete the sentence and answer the question. The higher the value of the principal quantum number for an electron, the less strongly bound to the atom it is. Therefore, option (1) is our final answer.