Deck 8: Electron Configuration and Chemical Periodicity

Question 1

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

Answer 1

5

Question 2

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, -½
B) 5, 1, 0, ½
C) 5, 0, 1, ½
D) 5, 1, 1, ½
E) 5, 0, 0, -½

Answer 2

5, 0, 0, -½

Question 3

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 ml = -1 m_s = +½
B) n = 3 l = 0 ml = 0 m_s = -½
C) n = 3 l = 2 ml = -2 m_s = -½
D) n = 4 l = 0 ml = 0 m_s = -½
E) n = 4 l = 2 ml = 1 m_s = +½

Answer 3

n = 4 l = 2 ml = 1 m_s = +½

Question 4

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 these choices are correct.

Question 5

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, ½
B) 5, 2, 0, ½
C) 5, 1, 2, ½
D) 5, 1, 0, ½
E) 5, 2, 1, ½

Question 6

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

A) 3d
B) 4s
C) 4p
D) 4d
E) 5s

Question 7

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

A) [Kr]5s²5p⁶4d⁸
B) [Kr]5s²5d¹⁰5p⁴
C) [Kr]5s²4d¹⁰5p⁶
D) [Kr]5s²4f¹⁴
E) [Kr]5s²4d¹⁰5p⁴

Question 8

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 9

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, ml = -2.

Question 10

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 11

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 these choices are correct.

Question 12

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.

Question 13

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 14

"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 15

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, ½
B) 4, 1, 0, ½
C) 4, 0, 1, ½
D) 4, 0, 0, ½
E) 4, 1, 1, ½

Question 16

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 17

The electronic structure 1s²2s²2p⁶3s²3p⁶4s²3d⁸ refers to the ground state of

A) Kr.
B) Ni.
C) Fe.
D) Pd.
E) None of these choices are correct.

Question 18

"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 19

Which of the following electron configurations is impossible?

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

Question 20

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

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

Question 21

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

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

Question 22

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 these choices are correct.

Question 23

Which of the following elements has the smallest atomic radius?

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

Question 24

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 25

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

A) X(s) → X⁺(g) + e^-
B) X2(g) → X⁺(g) + X^-(g)
C) X(g) + e^- → X^-(g)
D) X^-(g) → X(g) + e^-
E) X(g) → X⁺(g) + e^-

Question 26

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

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

Question 27

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 28

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 29

Which of the following elements has the greatest atomic radius?

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

Question 30

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 31

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

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

Question 32

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 33

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 34

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

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

Question 35

Which of the following elements has the smallest atomic size?

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

Question 36

Which of the following elements has the largest atomic size?

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

Question 37

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

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

Question 38

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 39

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 these choices are correct.

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

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

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

Question 42

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 43

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 44

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 these choices are correct.

Question 45

Select the most basic compound from the following.

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

Question 46

Select the element with the least metallic character.

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

Question 47

Select the paramagnetic ion.

A) Cu⁺
B) Ag⁺
C) Fe³⁺
D) Cd²⁺
E) Ca²⁺

Question 48

Which of the following elements is paramagnetic?

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

Question 49

Select the most acidic compound from the following.

A) SO₂
B) Al₂O₃
C) CaO
D) PbO
E) H₂O

Question 50

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 these choices are correct.

Question 51

Which of the following atoms will be diamagnetic?

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

Question 52

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 these choices are correct.

Question 53

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 these choices are correct.

Question 54

Select the diamagnetic ion.

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

Question 55

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 56

Which of the following has the most negative electron affinity?

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

Question 57

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 58

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

Question 59

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 60

Select the element with the greatest metallic character.

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

Question 61

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

Question 62

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

Question 63

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

Question 64

A negative electron affinity implies that the atom repels an approaching electron.

Question 65

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

Question 66

Electron affinities of neutral atoms may be positive or negative.

Question 67

Bigger atoms generally have smaller ionization energies.

Question 68

Electron affinities become increasingly positive toward the right hand end of a period.

Question 69

In moving down a group in the periodic table, the oxides of the elements become more acidic in nature.

Question 70

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

Question 71

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

Question 72

In forming ions of the first series of transition metals, the 4s electrons are lost before the 3d electrons.

Question 73

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

Question 74

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

Question 75

Consider the element with the electron configuration: [Rn]7s25f7. How would you classify this element?

A) a representative element
B) a transition metal
C) a nonmetal
D) an actinide element
E) a noble gas

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

Which one of the following oxides does not react with water to form acid solutions?

A) CO₂
B) SO₃
C) BaO
D) NO₂
E) Cl₂O₇