Answer :
To determine the electron configuration for zinc (Zn) and technetium (Tc) in noble-gas notation, we use the periodic table as a guide.
1. Zinc (Zn):
- Zinc has an atomic number of 30, which means it has 30 electrons.
- Starting from the closest noble gas before zinc, we find argon (Ar), which has an atomic number of 18. This allows us to use the noble-gas shorthand notation.
- After argon, the electrons are filled in the following order: 4s and then 3d.
- 4s²: The first two electrons go into the 4s subshell.
- 3d¹⁰: The next ten electrons fill the 3d subshell.
- Therefore, the electron configuration of zinc in noble-gas notation is:
[tex]\[ [\text{Ar}] 3d^{10} 4s^2 \][/tex]
2. Technetium (Tc):
- Technetium has an atomic number of 43, meaning it has 43 electrons.
- The nearest noble gas before technetium is krypton (Kr), with an atomic number of 36.
- After krypton, the electron filling order continues with the 5s and 4d subshells:
- 5s²: The first two electrons after krypton fill the 5s subshell.
- 4d⁵: The next five electrons fill the 4d subshell.
- The electron configuration of technetium in noble-gas notation is thus:
[tex]\[ [\text{Kr}] 4d^5 5s^2 \][/tex]
By identifying the closest noble gas and then following the Aufbau principle for filling electron orbitals, we can accurately write the noble-gas electron configurations for zinc and technetium.
1. Zinc (Zn):
- Zinc has an atomic number of 30, which means it has 30 electrons.
- Starting from the closest noble gas before zinc, we find argon (Ar), which has an atomic number of 18. This allows us to use the noble-gas shorthand notation.
- After argon, the electrons are filled in the following order: 4s and then 3d.
- 4s²: The first two electrons go into the 4s subshell.
- 3d¹⁰: The next ten electrons fill the 3d subshell.
- Therefore, the electron configuration of zinc in noble-gas notation is:
[tex]\[ [\text{Ar}] 3d^{10} 4s^2 \][/tex]
2. Technetium (Tc):
- Technetium has an atomic number of 43, meaning it has 43 electrons.
- The nearest noble gas before technetium is krypton (Kr), with an atomic number of 36.
- After krypton, the electron filling order continues with the 5s and 4d subshells:
- 5s²: The first two electrons after krypton fill the 5s subshell.
- 4d⁵: The next five electrons fill the 4d subshell.
- The electron configuration of technetium in noble-gas notation is thus:
[tex]\[ [\text{Kr}] 4d^5 5s^2 \][/tex]
By identifying the closest noble gas and then following the Aufbau principle for filling electron orbitals, we can accurately write the noble-gas electron configurations for zinc and technetium.
