Question 1

Select the correct set of quantum numbers (n, l, m_l, m_s) for the highest energy electron in the ground state of potassium, K. A) 4, 1, -1, B) 4, 1, 0, C) 4, 0, 1, D) 4, 0, 0, E) 4, 1, 1,

Accepted Answer

D

Question 2

Select the correct electron configuration for Te (Z = 52). A) [Kr]5s²5p⁶4d⁸ B) [Kr]5s²5d¹⁰5p⁴ C) [Kr]5s²4d¹⁰5p⁶ D) [Kr]5s²4f¹⁴ E) [Kr]5s²4d¹⁰5p⁴

Accepted Answer

E

Question 3

Which one of the following statements about orbital energies is incorrect?
A) In the hydrogen atom, the energy of an orbital depends only on the value of the quantum number n.
B) In many-electron atoms the energy of an orbital depends on both n and l.
C) Inner electrons shield outer electrons more effectively than do electrons in the same orbital.
D) The splitting of sublevels in many-electron atoms is explained in terms of the penetration effect.
E) The energy of a given orbital increases as the nuclear charge Z increases.

Accepted Answer

The energy of a given orbital actually decreases as the nuclear charge Z increases, due to increased electron attraction towards the nucleus.

Question 4

Which one of the following statements about atomic structure and quantum numbers is incorrect? A) In a given atom, the maximum number of electrons having principal quantum number n = 3, is 18. B) The number of orbitals in a given f subshell is 7. C) For n = 4, the largest possible value of l is 3. D) For n = 4, the largest possible value of m_l is 2. E) The following set of quantum numbers for a single orbital is not allowed: n = 3, l = 1, m_l = -2.

Accepted Answer

There is no quantum number called m_l. The correct quantum numbers are ms (spin quantum number), l (azimuthal quantum number), and ml (magnetic quantum number). The largest possible value of ml for n = 4 and l = 3 is 3.

Question 5

Select the correct electron configuration for sulfur (Z = 16). A) 1s²1p⁶2s²2p⁶ B) 1s²2s²2p⁸3s²3p⁴ C) 1s²2s²2p⁸3s²3p² D) 1s²2s²2p⁶3s²3p⁴ E) 1s²2s²2p⁶3s²3d⁴

Accepted Answer

The answer of Select the correct electron configuration for sulfur...

Question 6

The effective nuclear charge for an atom is less than the actual nuclear charge due to
A) shielding.
B) penetration.
C) paramagnetism.
D) electron-pair repulsion.
E) relativity.

Accepted Answer

Shielding occurs when the negatively charged electrons in an atom's outer electron shell partially cancel out some of the positively charged protons in the nucleus, resulting in a reduced effective nuclear charge.

Question 7

Select the correct electron configuration for Cu (Z = 29). A) [Ar]4s²3d⁹ B) [Ar]4s¹3d¹⁰ C) [Ar]4s²4p⁶3d³ D) [Ar]4s²4d⁹ E) [Ar]5s²4d⁹

Accepted Answer

The correct electron configuration for Cu (Z = 29) is [Ar] 3d^10 4s^1, which corresponds to the choice that indicates a full 3d subshell (10 electrons) and a single electron in the 4s subshell.

Question 8

How many valence electrons are there in an atom with the electron configuration [noble gas]ns²(n - 1)d¹⁰np³? A) 2 B) 3 C) 5 D) 10 E) 15

Accepted Answer

The answer of How many valence electrons are there in...

Question 9

Select the correct set of quantum numbers (n, l, m_l, m_s) for the first electron removed in the formation of a cation for strontium, Sr. A) 5, 1 , 0, - B) 5, 1, 0, C) 5, 0, 1, D) 5, 1, 1, E) 5, 0, 0, -

Accepted Answer

The answer of Select the correct set of quantum numbers...

Question 10

Energy states of atoms containing more than one electron arise from nucleus-electron and electron-electron interactions. Which of the following statements correctly describes these effects?
A) Larger nuclear charge lowers energy, more electrons in an orbital lowers energy.
B) Larger nuclear charge lowers energy, more electrons in an orbital increases energy.
C) Smaller nuclear charge lowers energy, more electrons in an orbital lowers energy.
D) Smaller nuclear charge lowers energy, more electrons in an orbital increases energy.
E) None of the above statements is generally correct.

Accepted Answer

Larger nuclear charge, or higher atomic number, attracts electrons more strongly and therefore lowers their energy. However, having more electrons in an orbital increases electron-electron repulsions, which raises their energy. This effect is known as electron-electron repulsion or electron correlation, and it leads to the splitting of electron energy levels in multi-electron atoms. Therefore, the correct statement is that larger nuclear charge lowers energy, while more electrons in an orbital increase energy.

Question 11

The electronic structure 1s²2s²2p⁶3s²3p⁶4s²3d⁸ refers to the ground state of A) Kr. B) Ni. C) Fe. D) Pd. E) none of the above.

Accepted Answer

The electronic configuration 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d⁸ corresponds to Nickel (Ni), which has an atomic number of 28.

Question 12

Which of the following electron configurations is impossible? A) 1s²2s²2p⁶3s²3p⁴ B) 1s²2s²2p⁵3s¹3p⁴ C) 1s²2s²2p⁶3s²3p⁶3d¹⁰4s² D) 1s²2s²2p⁶3s³3p⁴ E) 1s¹2s²2p⁶3s²3p⁴

Accepted Answer

The answer of Which of the following electron configurations is...

Question 13

Select the correct set of quantum numbers (n, l, m_l, m_s) for the highest energy electron in the ground state of tin, Sn. A) 5, 2, -1, B) 5, 2, 0, C) 5, 1, 2, D) 5, 1, 0, E) 5, 2, 1,

Accepted Answer

The answer of Select the correct set of quantum numbers...

Question 14

Which of the following sublevels is filled last? 3d, 4s, 4p, 4d, 5s
A) 3d
B) 4s
C) 4p
D) 4d
E) 5s

Accepted Answer

The sublevel that is filled last is the highest energy level. In this case, the highest energy level is the fourth energy level. Within the fourth energy level, sublevels are filled in order of increasing energy: 4s, 4p, 4d. Therefore, the sublevel that is filled last would be 4d.

Question 15

"Each electron in an atom must have its own unique set of quantum numbers" is a statement of
A) the aufbau principle.
B) the Pauli exclusion principle.
C) Hund's rule.
D) the periodic law.
E) Heisenberg's principle.

Accepted Answer

The statement refers to the Pauli exclusion principle, which states that no two electrons in an atom can have the same set of four quantum numbers. This is because electrons are fermions and are subject to the laws of quantum mechanics, including the principle of indistinguishability, which states that identical fermions cannot occupy the same quantum state simultaneously.

Question 16

An atom of element number 33 (As) is in its ground electronic state. Which one of the following sets quantum numbers could not apply to any of its electrons? A) n = 2 l = 1 m_l = -1 m_s = + B) n = 3 l = 0 m_l = 0 m_s = - C) n = 3 l = 2 m_l = -2 m_s = - D) n = 4 l = 0 m_l = 0 m_s = - E) n = 4 l = 2 m_l = 1 m_s = +

Accepted Answer

The answer of An atom of element number 33 (As)...

Question 17

In the ground state of an atom of silver (Ag), how many electrons will there be with the quantum number l = 1? (The n, m_l, and m_s quantum numbers may have any appropriate values.) A) 9 B) 12 C) 18 D) 24 E) 36

Accepted Answer

The answer of In the ground state of an atom...

Question 18

"Electrons added to atomic orbitals of the same energy will remain unpaired with parallel spins until the subshell is more than half-filled" is a statement of
A) the aufbau principle.
B) Hund's rule.
C) the Pauli exclusion principle.
D) the periodic law.
E) the singularity rule.

Accepted Answer

This statement is a restatement of Hund's rule, which states that electrons will fill orbitals singly with parallel spins before pairing up with opposite spins. This rule applies to subshells of the same energy level.

Question 19

In a single atom, what is the maximum number of electrons which can have quantum number n = 4?
A) 16
B) 18
C) 32
D) 36
E) none of the above

Accepted Answer

The maximum number of electrons in a shell is given by 2n^2. For n = 4, the maximum is 2(4)^2 = 32.

Question 20

In many-electron atoms, which quantum numbers specify the energy of an electron? A) n and l B) n and m_l C) l and m_l D) n and m_s E) n, l, and m_l

Accepted Answer

The energy of an electron in a many-electron atom is primarily determined by its principal quantum number (n) and its angular momentum quantum number (l). The other quantum numbers, including the spin quantum number (mS), do not directly specify the energy of the electron.

Quiz 8: Electron Configuration and Chemical Periodicity

Select the correct set of quantum numbers (n, l, m_l, m_s) for the highest energy electron in the ground state of potassium, K.

Select the correct electron configuration for Te (Z = 52) .

Which one of the following statements about orbital energies is incorrect?

Which one of the following statements about atomic structure and quantum numbers is incorrect?

Select the correct electron configuration for sulfur (Z = 16) .

The effective nuclear charge for an atom is less than the actual nuclear charge due to

Select the correct electron configuration for Cu (Z = 29) .

How many valence electrons are there in an atom with the electron configuration [noble gas]ns²(n - 1) d¹⁰np³?

Select the correct set of quantum numbers (n, l, m_l, m_s) for the first electron removed in the formation of a cation for strontium, Sr.

Energy states of atoms containing more than one electron arise from nucleus-electron and electron-electron interactions. Which of the following statements correctly describes these effects?

The electronic structure 1s²2s²2p⁶3s²3p⁶4s²3d⁸ refers to the ground state of

Which of the following electron configurations is impossible?

Select the correct set of quantum numbers (n, l, m_l, m_s) for the highest energy electron in the ground state of tin, Sn.

Which of the following sublevels is filled last? 3d, 4s, 4p, 4d, 5s

"Each electron in an atom must have its own unique set of quantum numbers" is a statement of

An atom of element number 33 (As) is in its ground electronic state. Which one of the following sets quantum numbers could not apply to any of its electrons?

In the ground state of an atom of silver (Ag) , how many electrons will there be with the quantum number l = 1? (The n, m_l, and m_s quantum numbers may have any appropriate values.)

"Electrons added to atomic orbitals of the same energy will remain unpaired with parallel spins until the subshell is more than half-filled" is a statement of

In a single atom, what is the maximum number of electrons which can have quantum number n = 4?

In many-electron atoms, which quantum numbers specify the energy of an electron?