e configuration GRADE A
When an electron moves from a lower to a higher energy level, the electron ___.
A. Always doubles its energy
B. Absorbs a continuously variable amount of energy
C. Absorbs a quantum of energy
D. Moves closer to the nucleus - (correct answer)c
All of the subshells in a given shell have the same energy in the hydrogen atom. In a
many-electron atom, the
subshells in a given shell do not have the same energy. Why? - (correct
answer)Hydrogen atoms have only one electron. Therefore, in a hydrogen atom, the
energy of orbitals depends only on n. In many-electron atoms, electron-electron
repulsion causes the energies of subshells in a given shell to differ.
原子轨道能量随着原子序数的递增而变化，在原子序数为 1 的时候，第三主层轨道能量相
同。3s=3p=3d<4s
Which electron configuration represents a violation of the Pauli exclusion principle?
A. 1s: ↑ 2s: ↑ 2p: ↑ ↑ ↑
B. 1s: ↑↓ 2s: ↑↑ 2p: ↑
C. 1s: ↑↓ 2s: ↑
D. 1s: ↑↓ 2s: ↑↓ 2p: ↑ ↑
E. 1s: ↑↓ 2s: ↑↓ 2p: ↑↓ - (correct answer)b
Which electron configuration represents a violation of Hund's rule for an atom in its
ground state?
A. 1s: ↑↓ 2s: ↑↓ 2p: ↑↓
B. 1s: ↑↓ 2s: ↑↓ 2p: ↑ ↑ ↑
C. 1s: ↑↑ 2s: ↑↓
D. 1s: ↑ 2s: ↑↓
, E. 1s: ↑↓ 2s: ↑↓ 2p: ↑ ↑ - (correct answer)a
Which of the following electron configurations is most stable?
A. a filled principal energy level
B. a half-filled energy sublevel
C. one empty and one filled energy sub level
D. a filled energy sublevel - (correct answer)a
If the spin of one electron in an orbital is clockwise, what is the spin of the other electron
in that orbital?
A. zero
B. clockwise
C. counterclockwise
D. both clockwise and counterclockwise - (correct answer)C. counterclockwise
If three electrons are avalible to fill three empty 2p atomic orbitals, how will the elctrons
be distributed in the three orbitals?
A. One electron in each orbital
B. two electrons in one orbital, one in another, none in the third
C. three in one orbital, none in the other two
D. three electrons cannot fill empty 2p atomic orbitals - (correct answer)a
how many unpaired electrons are in a sulfur atom (atomic number 16)?
A. 0
B. 1
C. 2
D. 3 - (correct answer)c
When an electron moves from a lower to a higher energy level, the electron ___.
A. Always doubles its energy
B. Absorbs a continuously variable amount of energy
C. Absorbs a quantum of energy
D. Moves closer to the nucleus - (correct answer)c
All of the subshells in a given shell have the same energy in the hydrogen atom. In a
many-electron atom, the
subshells in a given shell do not have the same energy. Why? - (correct
answer)Hydrogen atoms have only one electron. Therefore, in a hydrogen atom, the
energy of orbitals depends only on n. In many-electron atoms, electron-electron
repulsion causes the energies of subshells in a given shell to differ.
原子轨道能量随着原子序数的递增而变化，在原子序数为 1 的时候，第三主层轨道能量相
同。3s=3p=3d<4s
Which electron configuration represents a violation of the Pauli exclusion principle?
A. 1s: ↑ 2s: ↑ 2p: ↑ ↑ ↑
B. 1s: ↑↓ 2s: ↑↑ 2p: ↑
C. 1s: ↑↓ 2s: ↑
D. 1s: ↑↓ 2s: ↑↓ 2p: ↑ ↑
E. 1s: ↑↓ 2s: ↑↓ 2p: ↑↓ - (correct answer)b
Which electron configuration represents a violation of Hund's rule for an atom in its
ground state?
A. 1s: ↑↓ 2s: ↑↓ 2p: ↑↓
B. 1s: ↑↓ 2s: ↑↓ 2p: ↑ ↑ ↑
C. 1s: ↑↑ 2s: ↑↓
D. 1s: ↑ 2s: ↑↓
, E. 1s: ↑↓ 2s: ↑↓ 2p: ↑ ↑ - (correct answer)a
Which of the following electron configurations is most stable?
A. a filled principal energy level
B. a half-filled energy sublevel
C. one empty and one filled energy sub level
D. a filled energy sublevel - (correct answer)a
If the spin of one electron in an orbital is clockwise, what is the spin of the other electron
in that orbital?
A. zero
B. clockwise
C. counterclockwise
D. both clockwise and counterclockwise - (correct answer)C. counterclockwise
If three electrons are avalible to fill three empty 2p atomic orbitals, how will the elctrons
be distributed in the three orbitals?
A. One electron in each orbital
B. two electrons in one orbital, one in another, none in the third
C. three in one orbital, none in the other two
D. three electrons cannot fill empty 2p atomic orbitals - (correct answer)a
how many unpaired electrons are in a sulfur atom (atomic number 16)?
A. 0
B. 1
C. 2
D. 3 - (correct answer)c
