Deck 8: Electron Configuration and Chemical Periodicity

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,

Answer 1

4, 0, 0,

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

Answer 2

[Kr]5s²4d¹⁰5p⁴

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.

Answer 3

The energy of a given orbital increases as the nuclear charge Z increases.

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.

Question 5

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

A) 1s²1p⁶2s²2p⁶
B) 1s²2s²2p⁸3s²3p⁴
C) 1s²2s²2p⁸3s²3p²
D) 1s²2s²2p⁶3s²3p⁴
E) 1s²2s²2p⁶3s²3d⁴

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.

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

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

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, -

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.

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.

Question 12

Which of the following electron configurations is impossible?

A) 1s²2s²2p⁶3s²3p⁴
B) 1s²2s²2p⁵3s¹3p⁴
C) 1s²2s²2p⁶3s²3p⁶3d¹⁰4s²
D) 1s²2s²2p⁶3s³3p⁴
E) 1s¹2s²2p⁶3s²3p⁴

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,

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

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.

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 = +

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

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.

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

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

Question 21

Which of the following electron configurations represents the ground state of an element?

A) [Ne]3s¹3p¹
B) [He]2s¹2p³
C) [Ne]3s²3p²3d¹
D) [Ne]3s²3p³3d¹
E) [Ne]3s²3p³

Question 22

In the electron configuration [Ar]4s²3d¹⁰4p⁴, which are valence electrons?

A) all of the electrons after the [Ar]
B) only the 4s² electrons
C) only the 3d¹⁰ electrons
D) only the 4p⁴ electrons
E) both the 4s² and the 4p⁴ electrons

Question 23

When comparing the successive ionization energies of an element, an unusually big increase in ionization energy is seen when

A) the first valence electron is removed.
B) the second valence electron is removed.
C) the eighth electron of is removed.
D) the first core electron is removed.
E) the last valence electron is removed.

Question 24

Which of the following elements has the smallest atomic radius?

A) Li
B) Ne
C) Rb
D) Sr
E) Xe

Question 25

Which of the following elements has the greatest atomic radius?

A) Li
B) Ne
C) Rb
D) Sr
E) Xe

Question 26

Which of the following elements has the smallest atomic size?

A) Na
B) Ar
C) K
D) Ca
E) Kr

Question 27

Which of the following elements has the largest atomic size?

A) S
B) Ca
C) Ba
D) Po
E) Rn

Question 28

Elements with the highest first ionization energies are found in the ___________ region of the periodic table.

A) lower left
B) upper left
C) center
D) lower right
E) upper right

Question 29

Which one of the following equations correctly represents the process relating to the ionization energy of X?

A) X(s) $\to$ X⁺(g) + e^-
B) X₂(g) $\to$ X⁺(g) + X^-(g)
C) X(g) + e^- $\to$ X^-(g)
D) X^-(g) $\to$ X(g) + e^-
E) X(g) $\to$ X⁺(g) + e^-

Question 30

Which of the following fourth-period elements has the smallest atomic radius?

A) K
B) Ti
C) Cu
D) Ge
E) Kr

Question 31

Which of the following electron configurations is not possible for an atom in an excited state?

A) 1s²2s²2p⁶3s²3p⁶3d¹⁰4s¹4p¹
B) 1s²2s²2p⁶3s¹3p⁵
C) 1s²2s²2p⁶3s²3p²3d²
D) 1s²2s²2p⁶3s²3p⁶3d¹⁰4s²
E) 1s²2s²2p⁶3s²3p⁶3d¹⁰4s¹⁴p³

Question 32

Identify the element of Period 2 which has the following successive ionization energies, in kJ/mol. IE₁, 1314 IE₂, 3389 IE₃, 5298 IE₄, 7471
IE₅, 10992 IE₆, 13329 IE₇, 71345 IE₈, 84087

A) Li
B) B
C) O
D) Ne
E) none of the above

Question 33

Which of the following elements has the largest second ionization energy (IE₂)?

A) Li
B) B
C) O
D) F
E) Na

Question 34

Which of the following sets of elements have the [noble gas]ns²np² valence electron configuration?

A) O, S, Se, Te, Po
B) N, P, As, Sb, Bi
C) F, Cl, Br, I, At
D) C, Si, Ge, Sn, Pb
E) Ti, Zr, Hf

Question 35

Select the element with the most negative electron affinity (i.e., accepts an electron most readily).

A) H
B) Li
C) C
D) F
E) Ne

Question 36

Which one of the following equations correctly represents the process involved in the electron affinity of X?

A) X(g) $\to$ X⁺(g) + e^-
B) X⁺(g) $\to$ X⁺(aq)
C) X⁺(g) + e^- $\to$ X(g)
D) X(g) + e^- $\to$ X^-(g)
E) X⁺(g) + Y^-(g) $\to$ XY(s)

Question 37

How many valence electrons are there in an atom with the electron configuration [noble gas]ns²(n - 1)d⁸?

A) 2
B) 6
C) 8
D) 10
E) none of the above

Question 38

Which of the following elements has the smallest first ionization energy?

A) Rb
B) Mg
C) I
D) As
E) F

Question 39

Which of the following elements has the largest first ionization energy?

A) Na
B) Cl
C) Ca
D) Te
E) Br

Question 40

Which of the following electron configurations is correct for the excited state of an element?

A) [He]2s²2p⁵
B) [Ne]3s²3p¹
C) [Ar]4s¹4p¹
D) [Kr]5s²4d⁷
E) [He]1p¹

Question 41

Select the diamagnetic ion.

A) Cu²⁺
B) Ni²⁺
C) Cr³⁺
D) Sc³⁺
E) Cr²⁺

Question 42

Select the most acidic compound from the following:

A) SO₂
B) Al₂O₃
C) CaO
D) PbO
E) H₂O

Question 43

Which of the following has the most negative electron affinity?

A) H
B) Li
C) Na
D) K
E) Rb

Question 44

Consider the set of isoelectronic atoms and ions A^2-, B^-, C, D⁺, and E²⁺. Which arrangement of relative radii is correct?

A) A^2- > B^- > C > D⁺ > E²⁺
B) E²⁺ > D⁺ > C > B^- > A^2-
C) A^2- > B^- > C < D⁺ < E²⁺
D) A^2- < B^- < C > D⁺ > E²⁺
E) None of the above is correct.

Question 45

In a single atom, write down the maximum possible number of electrons
a. with n = 3
b. with the designation 4d_xy
c. with n = 5, l = 3, m_s = +

Question 46

Elements with _______________ first ionization energies and ___________ electron affinities generally form anions.

A) low, very negative
B) high, positive or slightly negative
C) low, positive or slightly negative
D) high, very negative
E) None of the above is generally correct.

Question 47

The most basic oxides are formed from elements found in the __________________ region of the periodic table.

A) upper right
B) upper left
C) center
D) lower right
E) lower left

Question 48

Write down the maximum number of electrons in an atom which can have
a. quantum number n = 4.
b. orbital designation 3d.
c. orbital designation 2p_z.

Question 49

Metallic behavior is generally associated with

A) elements with very negative electron affinities.
B) elements with low ionization energies.
C) elements with small atomic radii.
D) elements with unpaired electrons.
E) elements with partially filled p orbitals.

Question 50

Select the paramagnetic ion.

A) Cu⁺
B) Ag⁺
C) Fe³⁺
D) Cd²⁺
E) Ca²⁺

Question 51

Which of the following atoms will be diamagnetic?

A) Cr
B) Ru
C) Fe
D) Pt
E) Cd

Question 52

Which of the following ions will be most likely to form when selenium ionizes?

A) Se⁶⁺
B) Se⁴⁺
C) Se²⁺
D) Se^2-
E) Se^4-

Question 53

Select the most basic compound from the following:

A) Bi₂O₃
B) SiO₂
C) Cs₂O
D) Na₂O
E) H₂O

Question 54

Select the element with the least metallic character.

A) Sn
B) Sr
C) Tl
D) Ge
E) Ga

Question 55

Select the element with the greatest metallic character.

A) Li
B) Ca
C) Al
D) Pb
E) Cs

Question 56

Elements with ________________ first ionization energies and ___________ electron affinities generally form cations.

A) low, very negative
B) high, positive or slightly negative
C) low, positive or slightly negative
D) high, very negative
E) None of the above is generally correct.

Question 57

What is the correct order of decreasing size of the following ions?

A) P^3- > Cl^- > K⁺ > Ca²⁺
B) Ca²⁺ > K⁺ > Cl^- > P^3-
C) K⁺ > Cl^- > Ca²⁺ > P^3-
D) K⁺ > Cl^- > P^3- > Ca²⁺
E) None of the above is correct.

Question 58

Which of the following elements is paramagnetic?

A) Kr
B) Zn
C) Sr
D) V
E) Ar

Question 59

The most acidic oxides are formed from elements found in the _________________ region of the periodic table.

A) upper right
B) upper left
C) center
D) lower right
E) lower left

Question 60

Which of the following elements will form a cation with a +2 charge?

A) Si
B) Sr
C) Ga
D) Cs
E) S

Question 61

Define what is meant by electron affinity, and write a balanced chemical equation to represent the relevant process for element Y.

Question 62

In neutral atoms, the 3d orbitals have higher energy than the 4s orbitals.

Question 63

Hund's rule is used to predict the electron configuration of atoms in excited states.

Question 64

Elements in which the outermost electron has the same principal quantum number n, show similar chemical properties.

Question 65

Describe how the ionization energies of main group elements vary across a period in the periodic table, using a diagram if necessary.

Question 66

Briefly describe how the atomic radii and ionization energies of group 1A(1) elements compare with those of group 8A(18). Also, explain why the values of these properties are so different between these two groups.

Question 67

Elements in the same period of the periodic table have similar valence shell electron configurations.

Question 68

Write down the full electron configuration for ground state atoms of
a. element number 12.
b. element number 23.
c. element number 32.

Question 69

Atomic size decreases across a period due to an increase in the effective nuclear charge, Z_eff.

Question 70

In Mendeleev's version of the periodic table, the elements were arranged in order of increasing atomic number.

Question 71

Bigger atoms generally have smaller ionization energies.

Question 72

State Hund's rule, and show how it applies to the ground state of phosphorus atoms.

Question 73

Write down the full electron configuration for ground state atoms of
a. S (element 16).
b. Pd (element 46).

Question 74

Moseley's measurements of nuclear charges of the elements provided the basis for arranging the elements of the periodic table in order of increasing atomic number.

Question 75

The maximum number of electrons in an atom with the same value of n is 2n².

Question 76

According to the exclusion principle, two is the maximum number of electrons in an atom which can share the same four quantum numbers.

Question 77

Define what is meant by ionization energy, and write a balanced chemical equation to represent the relevant process for element X.

Question 78

First ionization energies of neutral atoms may be positive or negative.

Question 79

Describe how the atomic radii of main group elements vary with position in the periodic table.

Question 80

The difference in energies between the 1s and 2s orbitals is due to the penetration effect.