What is the total number of principal energy levels or shells in an atom with an atomic number of 30? and why?
(1) 3
(2) 4
(3) 5
(4) 6
From the other post (with 29 electrons) just add one more electron (to which level?) and you will have it.
To determine the total number of principal energy levels or shells in an atom with an atomic number of 30, we need to understand the concept of atomic structure.
The atomic number of an element represents the number of protons in its nucleus. In a neutral atom, the number of protons is equal to the number of electrons. Electrons are arranged in energy levels or shells around the nucleus.
The maximum number of electrons that can occupy an energy level can be calculated using the formula 2n^2, where n represents the principal quantum number or the energy level.
So, for an atom with an atomic number of 30, we need to find the energy level that can accommodate 30 electrons. To do this, we can use the following steps:
1. Determine the nearest perfect square less than or equal to the given atomic number. In this case, the nearest perfect square less than or equal to 30 is 25.
2. Take the square root of the perfect square obtained in step 1. The square root of 25 is 5.
3. The result obtained in step 2 represents the maximum principal quantum number, which is equal to the total number of energy levels or shells in the atom. In this case, the total number of principal energy levels or shells in an atom with an atomic number of 30 is 5.
Therefore, the correct answer is option (3) 5.