For how many electrons in Sr. Does
A)n=4; l=1
B)n=3;l=2;ml=1
C)n=1;l=1;ml=0
You must know the variations possible.
n = 1, 2, 3, ......
l = 0, 1, 2, etc up to n-1.
ml=-l to +l (this is -ell to +ell)
ms = +/- 1/2
Start with n = 1 and work your way up.
To determine the number of electrons in an atom, you need to understand how electrons are distributed according to the quantum numbers. The quantum numbers n, l, ml, and ms are used to describe the electron's energy level, orbital shape, orientation, and spin, respectively.
Let's go through each option step by step:
A) For the given values n=4 and l=1, we start with the value of n. This tells us that the electron is in the fourth energy level or shell. Since l=1, it indicates that the electron is in a p orbital. For p orbitals, the ml values can be -1, 0, or 1. So, ml=1 indicates that the electron is in a p orbital with ml=1.
Now, according to the Pauli exclusion principle, each orbital can hold a maximum of 2 electrons (with opposite spins). Therefore, for this scenario, there can be a maximum of 2 electrons.
B) Here, n=3, l=2, and ml=1. Similar to before, n=3 indicates that the electron is in the third energy level or shell. Since l=2, it indicates that the electron is in a d orbital. For d orbitals, the ml values can be -2, -1, 0, 1, or 2. So, ml=1 indicates that the electron is in a d orbital with ml=1.
Again, using the Pauli exclusion principle, each orbital can hold a maximum of 2 electrons (with opposite spins). Therefore, for this scenario, there can be a maximum of 2 electrons.
C) In this case, n=1, l=1, and ml=0. Taking n=1 means that the electron is in the first energy level or shell. Since l=1, it indicates that the electron is in an s orbital. For s orbitals, there is only one allowed ml value, which is 0.
Applying the Pauli exclusion principle, we can see that each orbital can hold a maximum of 2 electrons (with opposite spins). Therefore, for this scenario, there can be a maximum of 2 electrons.
In summary:
A) n=4, l=1: Maximum of 2 electrons.
B) n=3, l=2, ml=1: Maximum of 2 electrons.
C) n=1, l=1, ml=0: Maximum of 2 electrons.
Thus, the maximum number of electrons in Sr for each of the given quantum number sets is 2.