In which orbital does an electron in a phosphorus atom experience the greatest effective nuclear charge?
a. 1s
b. 2s
c. 2p
d. 3s
e. 3p
I originally thought 3p, since those are the outer electrons, but that was marked wrong. Why is it not 3p? Is the right answer 3s then?
The 3p is right for the LEAST effective nuclear charge (remember those outer electrons aren't held strongly) but this is the opposite of that; therefore, the correct answer is 1s. There is no shielding for the 1s electrons. (Technically, the other electron in the 1s does offer some shielding; however, those 1s electrons SEE the highest pull from the protons in the nucleus.
1s, right?
1s
1s. because it is the nearest orbital to nucleus
1S
C
To determine the orbital in which an electron in a phosphorus atom experiences the greatest effective nuclear charge, we need to consider the concept of effective nuclear charge and the arrangement of electrons in an atom.
Effective nuclear charge refers to the net positive charge experienced by an electron in an atom. It takes into account the attractive force between the electron and the nucleus as well as the screening or shielding effect of other electrons. The effective nuclear charge generally increases as we move towards the nucleus.
In the case of phosphorus (P), the atomic number is 15, which means it has 15 electrons. These electrons are distributed in different orbitals according to the Aufbau principle and the Pauli exclusion principle. The electron configuration of phosphorus is:
1s^2 2s^2 2p^6 3s^2 3p^3
The first electron shell (1s) and the second electron shell (2s and 2p) are closer to the nucleus, while the third electron shell (3s and 3p) is further away from the nucleus.
Now, let's consider the options given:
a. 1s: This is the innermost orbital, and the electron experiences the highest effective nuclear charge due to its proximity to the nucleus.
b. 2s: The 2s orbital is closer to the nucleus than the 3s orbital, so the effective nuclear charge experienced by the electron in 2s is higher than in 3s.
c. 2p: The 2p orbital is also closer to the nucleus than the 3s orbital, so the effective nuclear charge experienced by the electron in 2p is higher than in 3s.
d. 3s: While the 3s orbital is further from the nucleus than the 2s and 2p orbitals, it is still closer to the nucleus than the 3p orbital.
e. 3p: The 3p orbital is further from the nucleus compared to the 3s orbital, so the effective nuclear charge experienced by the electron in 3s is higher than in 3p.
Therefore, the correct answer is d. 3s. The electron in the 3s orbital of a phosphorus atom experiences the greatest effective nuclear charge.