A tin atom has 50 electrons. Electrons in which sublevel of this atom would experience the lowest effective nuclear charge?
a. 1s
b. 3p
c. 3d
d. 4s
3. 5p
http://www.webelements.com/tin/atoms.html
Look for the outer electrons.
Oh, ok. So 5p?
right. Why? Because the 4p electrons have the shielding effect of the other 48 electrons in the lower levels so the attraction between the nucleus and the outer electrons are minimized.
To determine which sublevel of a tin atom would experience the lowest effective nuclear charge, we need to understand the concept of effective nuclear charge and how it changes across different electron sublevels.
Effective nuclear charge (Zeff) refers to the net positive charge experienced by an electron in an atom, taking into account the shielding effect of inner electrons. The more shielding an electron experiences from inner electrons, the lower the effective nuclear charge it will encounter.
The effective nuclear charge (Zeff) can be approximated using the formula:
Zeff = Z - S,
where Z is the atomic number (number of protons) and S is the shielding constant.
Now, let's consider the sublevels listed in the question: 1s, 3p, 3d, 4s, and 5p.
a. 1s:
The 1s sublevel consists of only one orbital and can hold a maximum of 2 electrons. Since tin has 50 electrons, it will fill all the lower energy sublevels before reaching the 1s sublevel. Therefore, the 1s sublevel will be shielded by all the other sublevels, resulting in the highest effective nuclear charge.
b. 3p:
The 3p sublevel consists of three orbitals and can hold a maximum of 6 electrons. Comparatively speaking, the 3p sublevel is slightly closer to the core than the higher sublevels but farther away than the 1s sublevel. It will experience some shielding from the inner electrons but will have a higher effective nuclear charge than the 1s sublevel.
c. 3d:
The 3d sublevel consists of five orbitals and can hold a maximum of 10 electrons. Similar to the 3p sublevel, it is farther from the core compared to the 1s sublevel but closer than the higher sublevels. The 3d sublevel will also experience some shielding from the inner electrons but will have a higher effective nuclear charge than the 1s sublevel.
d. 4s:
The 4s sublevel consists of one orbital and can hold a maximum of 2 electrons. It is farther from the core than both the 3p and 3d sublevels. Since it is higher in energy and farther from the nucleus, the electrons in the 4s sublevel will encounter the least effective nuclear charge among the options given.
e. 5p:
The 5p sublevel consists of three orbitals and can hold a maximum of 6 electrons. The 5p sublevel is farther from the core than both the 4s, 3p, and 3d sublevels. Therefore, the electrons in the 5p sublevel will experience a higher effective nuclear charge than the 4s sublevel.
Based on the analysis above, the sublevel with the lowest effective nuclear charge among the given options is:
d. 4s.