The electronic configuration of an element ,X , is represented by 1s2 2s2 2p6 3s2 3p6 3p6 4s2 and 3d3. Determine the atomic number of X
This can't be. You have typed two 3p6 levels and no two electrons can have the same quantum numbers in an atom. Either you have made a typo or the author of the problem has made an error. You can't have two 3p6 levels in the same element. This question, as posted, has no correct answer.
To determine the atomic number of element X, we can look at the electronic configuration. Each number in the configuration represents the number of electrons in the corresponding orbital.
The electronic configuration given is: 1s2 2s2 2p6 3s2 3p6 3p6 4s2 3d3
Now, let's break it down to count the total number of electrons:
1s2 represents 2 electrons in the 1s orbital.
2s2 represents 2 electrons in the 2s orbital.
2p6 represents 6 electrons in the 2p orbital.
3s2 represents 2 electrons in the 3s orbital.
3p6 represents 6 electrons in the 3p orbital.
3d3 represents 3 electrons in the 3d orbital.
Adding up the electrons from each orbital, we have:
2 + 2 + 6 + 2 + 6 + 3 = 21
Therefore, the atomic number of element X is 21 since the atomic number represents the number of protons in an atom, which is equal to the number of electrons in a neutral atom.
just count the number of electrons
the 1st number is the orbital ... the following letter is the suborbital (s, p, d)
the last number is the number of electrons in the suborbital
... add all these numbers