šŸŽ‰ Announcing Numerade's $26M Series A, led by IDG Capital!Read how Numerade will revolutionize STEM Learning

Chapter 3

Periodic Properties of the Elements

Educators

KC
+ 4 more educators

Problem 1

What are periodic properties?

KC
Kevin C.
Numerade Educator

Problem 2

Use aluminum as an example to explain how density is a periodic property.

Lyniesha W.
Numerade Educator

Problem 3

Explain the contributions of Dobereiner and Newlands to the organization of elements according to their properties.

KC
Kevin C.
Numerade Educator

Problem 4

Who is credited with arranging the periodic table? How are elements arranged in this table?

Lyniesha W.
Numerade Educator

Problem 5

Explain the contributions of Meyer and Moseley to the periodic table.

KC
Kevin C.
Numerade Educator

Problem 6

The periodic table is a result of the periodic law. What observations led to the periodic law? What theory explains the underlying reasons for the periodic law?

Lyniesha W.
Numerade Educator

Problem 7

What is an electron configuration? Provide an example.

KC
Kevin C.
Numerade Educator

Problem 8

What is Coulomb"s law? Explain how the potential energy of two charged particles depends on the distance between the charged particles and on the magnitude and sign of their charges.

Lyniesha W.
Numerade Educator

Problem 9

What is shielding? In an atom, which electrons tend to do the most shielding (core electrons or valence electrons)?

KC
Kevin C.
Numerade Educator

Problem 10

What is penetration? How does the penetration of an orbital into the region occupied by core electrons affect the energy of an electron in that orbital?

Lyniesha W.
Numerade Educator

Problem 11

Why are the sublevels within a principal level split into different energies for multi-electron atoms but not for the hydrogen atom?

KC
Kevin C.
Numerade Educator

Problem 12

What is an orbital diagram? Provide an example.

Lyniesha W.
Numerade Educator

Problem 13

Why is electron spin important when writing electron configurations? Explain in terms of the Pauli exclusion principle.

KC
Kevin C.
Numerade Educator

Problem 14

What are degenerate orbitals? According to Hund"s rule, how are degenerate orbitals occupied?

Lyniesha W.
Numerade Educator

Problem 15

List all orbitals from 1s through 5s according to increasing energy for multi-electron atoms.

KC
Kevin C.
Numerade Educator

Problem 16

What are valence electrons? Why are they important?

Lyniesha W.
Numerade Educator

Problem 17

Copy this blank periodic table onto a sheet of paper and label each of the blocks within the table: s block, p block, d block, and f block.

KC
Kevin C.
Numerade Educator

Problem 18

Explain why the s block in the periodic table has only two columns while the p block has six.

Lyniesha W.
Numerade Educator

Problem 19

Explain why the rows in the periodic table become progressively longer as we move down the table. For example, the first row contains two elements, the second and third rows each contain eight elements, and the fourth and fifth rows each contain 18 elements.

KC
Kevin C.
Numerade Educator

Problem 20

Explain the relationship between a main-group element"s lettered group number (the number of the element"s column) and its valence electrons.

Lyniesha W.
Numerade Educator

Problem 21

Explain the relationship between an element"s row number in the periodic table and the highest principal quantum number in the element"s electron configuration. How does this relationship differ for main group elements, transition elements, and inner transition elements?

KC
Kevin C.
Numerade Educator

Problem 22

Which of the transition elements in the first transition series have anomalous electron configurations?

Lyniesha W.
Numerade Educator

Problem 23

Explain how to write the electron configuration for an element based on its position in the periodic table.

KC
Kevin C.
Numerade Educator

Problem 24

Explain the relationship between the properties of an element and the number of valence electrons that it contains.

Lyniesha W.
Numerade Educator

Problem 25

List the number of valence electrons for each family in the periodic table, and explain the relationship between the number of valence electrons and the resulting chemistry of the elements in the family.

a. alkali metals
b. alkaline earth metals
c. halogens
d. oxygen family

KC
Kevin C.
Numerade Educator

Problem 26

Define atomic radius. For main-group elements, describe the observed trends in atomic radius as we:

a. move across a period in the periodic table
b. move down a column in the periodic table

Lyniesha W.
Numerade Educator

Problem 27

What is effective nuclear charge? What is shielding?

KC
Kevin C.
Numerade Educator

Problem 28

When an alkali metal forms an ion, what is the charge of the ion? What is the charge of an alkaline earth metal ion?

Lyniesha W.
Numerade Educator

Problem 29

When a halogen forms an ion, what is the charge of the ion? When the nonmetals in the oxygen family form ions, what is the charge of the ions? What is the charge of the ions formed by N and Al?

KC
Kevin C.
Numerade Educator

Problem 30

Use the concepts of effective nuclear charge, shielding, and n value of the valence orbital to explain the trend in atomic radius as we move across a period in the periodic table.

Lyniesha W.
Numerade Educator

Problem 31

For transition elements, describe the trends in atomic radius as we:

a. move across a period in the periodic table
b. move down a column in the periodic table

Explain the reasons for the trends described in parts a and b.

KC
Kevin C.
Numerade Educator

Problem 32

How is the electron configuration of an anion different from that of the corresponding neutral atom? How is the electron configuration of a cation different?

Lyniesha W.
Numerade Educator

Problem 33

Explain how to write an electron configuration for a transition metal cation. Is the order of electron removal upon ionization simply the reverse of electron addition upon filling? Why or why not?

KC
Kevin C.
Numerade Educator

Problem 34

Describe the relationship between:

a. the radius of a cation and the radius of the atom from which it is formed
b. the radius of an anion and the radius of the atom from which it is formed

Lyniesha W.
Numerade Educator

Problem 35

What is ionization energy? What is the difference between first ionization energy and second ionization energy?

KC
Kevin C.
Numerade Educator

Problem 36

What is the general trend in first ionization energy as we move down a column in the periodic table? As we move across a row?

Lyniesha W.
Numerade Educator

Problem 37

What are the exceptions to the periodic trends in first ionization energy? Why do they occur?

KC
Kevin C.
Numerade Educator

Problem 38

Examination of the first few successive ionization energies for a given element usually reveals a large jump between two ionization energies. For example, the successive ionization energies of magnesium show a large jump between IE2 and IE3. The successive ionization energies of aluminum show a large
jump between IE3 and IE4. Explain why these jumps occur and how we might predict them.

Lyniesha W.
Numerade Educator

Problem 39

What is electron affinity? What are the observed periodic trends in electron affinity?

KC
Kevin C.
Numerade Educator

Problem 40

What is metallic character? What are the observed periodic trends in metallic character?

Lyniesha W.
Numerade Educator

Problem 41

Write the name of each element and classify it as a metal, nonmetal, or metalloid.

a. K
b. Ba
c. I
d. O
e. Sb

KC
Kevin C.
Numerade Educator

Problem 42

Write the symbol for each element and classify it as a metal, nonmetal, or metalloid.

a. gold
b. fluorine
c. sodium
d. tin
e. argon

Lyniesha W.
Numerade Educator

Problem 43

Determine whether each element is a main-group element.

a. tellurium
b. potassium
c. vanadium
d. manganese

KC
Kevin C.
Numerade Educator

Problem 44

Determine whether each element is a transition element.

a. Cr
b. Br
c. Mo
d. Cs

Lyniesha W.
Numerade Educator

Problem 45

Write the full electron configuration for each element.

a. Si
b. O
c. K
d. Ne

KC
Kevin C.
Numerade Educator

Problem 46

Write the full electron configuration for each element.

a. C
b. P
c. Ar
d. Na

Lyniesha W.
Numerade Educator

Problem 47

Write the full orbital diagram for each element.

a. N
b. F
c. Mg
d. Al

KC
Kevin C.
Numerade Educator

Problem 48

Write the full orbital diagram for each element.

a. S
b. Ca
c. Ne
d. He

Lyniesha W.
Numerade Educator

Problem 49

Use the periodic table to write the electron configuration for each element. Represent core electrons with the symbol of the previous noble gas in brackets.

a. P
b. Ge
c. Zr
d. I

KC
Kevin C.
Numerade Educator

Problem 50

Use the periodic table to determine the element corresponding to each electron configuration.

a. [Ar] 4s2 3d10 4p6
b. [Ar] 4s2 3d2
c. [Kr] 5s2 4d10 5p2
d. [Kr] 5s2

Lyniesha W.
Numerade Educator

Problem 51

Use the periodic table to determine each quantity.

a. the number of 2s electrons in Li
b. the number of 3d electrons in Cu
c. the number of 4p electrons in Br
d. the number of 4d electrons in Zr

KC
Kevin C.
Numerade Educator

Problem 52

Use the periodic table to determine each quantity.

a. the number of 3s electrons in Mg
b. the number of 3d electrons in Cr
c. the number of 4d electrons in Y
d. the number of 6p electrons in Pb

Lyniesha W.
Numerade Educator

Problem 53

Name an element in the fourth period (row) of the periodic table with:

a. five valence electrons
b. four 4p electrons
c. three 3d electrons
d. a complete outer shell

Charotte M.
Numerade Educator

Problem 54

Name an element in the third period (row) of the periodic table with:

a. three valence electrons
b. four 3p electrons
c. six 3p electrons
d. two 3s electrons and zero 3p electrons

Lyniesha W.
Numerade Educator

Problem 55

Determine the number of valence electrons in each element.

a. Ba
b. Cs
c. Ni
d. S

KC
Kevin C.
Numerade Educator

Problem 56

Determine the number of valence electrons in each element. Which elements do you expect to lose electrons in chemical reactions? Which do you expect to gain electrons?

a. Al
b. Sn
c. Br
d. Se

Lyniesha W.
Numerade Educator

Problem 57

Which outer electron configuration would you expect to correspond to a reactive metal? To a reactive nonmetal?

a. ns2
b. ns2 np6
c. ns2 np5
d. ns2 np2

KC
Kevin C.
Numerade Educator

Problem 58

Which outer electron configuration would you expect to correspond to a noble gas? To a metalloid?

a. ns2
b. ns2 np6
c. ns2 np5
d. ns2 np2

Lyniesha W.
Numerade Educator

Problem 59

List the number of valence electrons for each element and classify each element as an alkali metal, alkaline earth metal, halogen, or noble gas.

a. sodium
b. iodine
c. calcium
d. barium
e. krypton

Charotte M.
Numerade Educator

Problem 60

List the number of valence electrons in each element and classify each element as an alkali metal, alkaline earth metal, halogen, or noble gas.

a. F
b. Sr
c. K d. Ne
e. At

Lyniesha W.
Numerade Educator

Problem 61

Which pair of elements do you expect to be most similar? Why?

a. N and Ni
b. Mo and Sn
c. Na and Mg
d. Cl and F
e. Si and P

Charotte M.
Numerade Educator

Problem 62

Which pair of elements do you expect to be most similar? Why?

a. nitrogen and oxygen
b. titanium and gallium
c. lithium and sodium
d. germanium and arsenic
e. argon and bromine

Lyniesha W.
Numerade Educator

Problem 63

Predict the charge of the ion formed by each element and write the electron configuration of the ion.

a. O
b. K
c. Al
d. Rb

Charotte M.
Numerade Educator

Problem 64

Predict the charge of the ion formed by each element and write the electron configuration of the ion.

a. Mg
b. N
c. F
d. Na

Lyniesha W.
Numerade Educator

Problem 65

According to Coulomb"s law, which pair of charged particles has the lowest potential energy?

a. a particle with a 1- charge separated by 150 pm from a particle with a 2+ charge
b. a particle with a 1- charge separated by 150 pm from a particle with a 1+ charge
c. a particle with a 1- charge separated by 100 pm from a particle with a 3+ charge

KC
Kevin C.
Numerade Educator

Problem 66

According to Coulomb"s law, rank the interactions between charged particles from lowest potential energy to highest potential energy.

a. a 1+ charge and a 1- charge separated by 100 pm
b. a 2+ charge and a 1- charge separated by 100 pm
c. a 1+ charge and a 1+ charge separated by 100 pm
d. a 1+ charge and a 1- charge separated by 200 pm

Charotte M.
Numerade Educator

Problem 67

Which electrons experience a greater effective nuclear charge: the valence electrons in beryllium or the valence electrons in nitrogen? Why?

KC
Kevin C.
Numerade Educator

Problem 68

Arrange the atoms according to decreasing effective nuclear charge experienced by their valence electrons: S, Mg, Al, Si.

Lyniesha W.
Numerade Educator

Problem 69

If core electrons completely shielded valence electrons from nuclear charge (i.e., if each core electron reduced nuclear charge by one unit) and if valence electrons did not shield one another from nuclear charge at all, what would be the effective nuclear charge experienced by the valence electrons of each atom?

a. K
b. Ca
c. O
d. C

Ronald P.
Numerade Educator

Problem 70

In Section 3.6, we estimated the effective nuclear charge on beryllium"s valence electrons to be slightly greater than 2+. What would a similar treatment predict for the effective nuclear charge on boron"s valence electrons? Would you expect the effective nuclear charge to be different for boron"s 2s electrons compared to its 2p electron? In what way? (Hint: Consider the shape of the 2p orbital compared to that of the 2s orbital.)

Ly T.
Numerade Educator

Problem 71

Choose the larger atom in each pair.

a. Al or In
b. Si or N
c. P or Pb
d. C or F

KC
Kevin C.
Numerade Educator

Problem 72

Choose the larger atom in each pair.

a. Sn or Si
b. Br or Ga
c. Sn or Bi
d. Se or Sn

Lyniesha W.
Numerade Educator

Problem 73

Arrange these elements in order of increasing atomic radius: Ca, Rb, S, Si, Ge, F.

KC
Kevin C.
Numerade Educator

Problem 74

Arrange these elements in order of decreasing atomic radius: Cs, Sb, S, Pb, Se.

Lyniesha W.
Numerade Educator

Problem 75

Write the electron configuration for each ion.

a. O2-
b. Br-
c. Sr2+
d. Co3+
e. Cu2+

KC
Kevin C.
Numerade Educator

Problem 76

Write the electron configuration for each ion.

a. Cl-
b. P3-
c. K-
d. Mo3+
e. V3+

Lyniesha W.
Numerade Educator

Problem 77

Write orbital diagrams for each ion and determine if the ion is diamagnetic or paramagnetic.

a. V5+
b. Cr3+
c. Ni2+
d. Fe3+

Charotte M.
Numerade Educator

Problem 78

Write orbital diagrams for each ion and determine if the ion is diamagnetic or paramagnetic.

a. Cd2+
b. Au+
c. Mo3+
d. Zr2+

Lyniesha W.
Numerade Educator

Problem 79

Which is the larger species in each pair?

a. Li or Li+
b. I- or Cs+
c. Cr or Cr3+
d. O or O2-

KC
Kevin C.
Numerade Educator

Problem 80

Which is the larger species in each pair?

a. Sr or Sr2+
b. N or N3-
c. Ni or Ni2+
d. S2- or Ca2+

David C.
Numerade Educator

Problem 81

Arrange this isoelectronic series in order of decreasing radius: F-, O2-, Mg2+, Na+.

KC
Kevin C.
Numerade Educator

Problem 82

Arrange this isoelectronic series in order of increasing atomic radius: Se2-, Sr2+, Rb+, Br-.

David C.
Numerade Educator

Problem 83

Choose the element with the higher first ionization energy in each pair.

a. Br or Bi
b. Na or Rb
c. As or At
d. P or Sn

KC
Kevin C.
Numerade Educator

Problem 84

Choose the element with the higher first ionization energy in each pair.

a. P or I
b. Si or Cl
c. P or Sb
d. Ga or Ge

Ly T.
Numerade Educator

Problem 85

Arrange these elements in order of increasing first ionization energy: Si, F, In, N.

KC
Kevin C.
Numerade Educator

Problem 86

Arrange these elements in order of decreasing first ionization energy: Cl, S, Sn, Pb.

Ly T.
Numerade Educator

Problem 87

For each element, predict where the 'jump' occurs for successive ionization energies. (For example, does the jump occur between the first and second ionization energies, the second and third, or the third and fourth?)

a. Be
b. N
c. O
d. Li

KC
Kevin C.
Numerade Educator

Problem 88

Consider this set of successive ionization energies:
IE1 = 578 kJ>mol IE2 = 1820 kJ>mol
IE3 = 2750 kJ>mol IE4 = 11,600 kJ>mol

To which third-period element do these ionization values belong?

Ly T.
Numerade Educator

Problem 89

Choose the element with the more negative (more exothermic) electron affinity in each pair.

a. Na or Rb
b. B or S
c. C or N
d. Li or F

Charotte M.
Numerade Educator

Problem 90

Choose the element with the more negative (more exothermic) electron affinity in each pair.

a. Mg or S
b. K or Cs
c. Si or P
d. Ga or Br

Ly T.
Numerade Educator

Problem 91

Choose the more metallic element in each pair.

a. Sr or Sb
b. As or Bi
c. Cl or O
d. S or As

Charotte M.
Numerade Educator

Problem 92

Choose the more metallic element in each pair.

a. Sb or Pb
b. K or Ge
c. Ge or Sb
d. As or Sn

DS
Da S.
Numerade Educator

Problem 93

Arrange these elements in order of increasing metallic character: Fr, Sb, In, S, Ba, Se.

KC
Kevin C.
Numerade Educator

Problem 94

Arrange these elements in order of decreasing metallic character: Sr, N, Si, P, Ga, Al.

Lyniesha W.
Numerade Educator

Problem 95

Bromine is a highly reactive liquid, whereas krypton is an inert gas. Explain the difference based on their electron configurations.

KC
Kevin C.
Numerade Educator

Problem 96

Potassium is a highly reactive metal, whereas argon is an inert gas. Explain the difference based on their electron configurations.

Lyniesha W.
Numerade Educator

Problem 97

Both vanadium and its 3+ ion are paramagnetic. Use electron configurations to explain this statement.

KC
Kevin C.
Numerade Educator

Problem 98

Use electron configurations to explain why copper is paramagnetic while its 1+ ion is not.

Ly T.
Numerade Educator

Problem 99

Suppose you were trying to find a substitute for K+ for some application. Where would you begin your search? Which ions are most like K+? For each ion you propose, explain the ways in which it is similar to K+ and the ways it is different. Refer to periodic trends in your discussion.

KC
Kevin C.
Numerade Educator

Problem 100

Suppose you were trying to find a substitute for Na+ for some application. Where would you begin your search? What ions are most like Na+? For each ion you propose, explain the ways in which it is similar to Na+ and the ways it is different. Use periodic trends in your discussion.

Ronald P.
Numerade Educator

Problem 101

Life on Earth evolved based on the element carbon. Based on periodic properties, what two or three elements would you expect to be most like carbon?

KC
Kevin C.
Numerade Educator

Problem 102

Which pair of elements would you expect to have the most similar atomic radii, and why?

a. Si and Ga
b. Si and Ge
c. Si and As

Ly T.
Numerade Educator

Problem 103

Consider these elements: N, Mg, O, F, Al.

a. Write the electron configuration for each element.
b. Arrange the elements in order of decreasing atomic radius.
c. Arrange the elements in order of increasing ionization energy.
d. Use the electron configurations in part a to explain the differences between your answers to parts b and c.

KC
Kevin C.
Numerade Educator

Problem 104

Consider these elements: P, Ca, Si, S, Ga.

a. Write the electron configuration for each element.
b. Arrange the elements in order of decreasing atomic radius.
c. Arrange the elements in order of increasing ionization energy.
d. Use the electron configurations in part a to explain the differences between your answers to parts b and c.

Ly T.
Numerade Educator

Problem 105

Explain why atomic radius decreases as we move to the right across a period for main-group elements but not for transition elements.

David C.
Numerade Educator

Problem 106

Explain why vanadium (radius = 134 pm) and copper (radius = 128 pm) have nearly identical atomic radii, even though the atomic number of copper is about 25% higher than that of vanadium. What would you predict about the relative densities of these two metals? Look up the densities in a reference
book, periodic table, or on the Internet. Are your predictions correct?

Ly T.
Numerade Educator

Problem 107

The lightest noble gases, such as helium and neon, are completely inert they do not form any chemical compounds whatsoever. The heavier noble gases, in contrast, do form a limited number of compounds. Explain this difference in terms of trends in fundamental periodic properties.

KC
Kevin C.
Numerade Educator

Problem 108

The lightest halogen is also the most chemically reactive, and reactivity generally decreases as we move down the column of halogens in the periodic table. Explain this trend in terms of periodic properties.

Ly T.
Numerade Educator

Problem 109

Write general outer electron configurations (nsxnpy) for groups 6A and 7A in the periodic table. The electron affinity of each group 7A element is more negative than that of each corresponding group 6A element. Use the electron configurations to explain this observation.

KC
Kevin C.
Numerade Educator

Problem 110

The electron affinity of each group 5A element is more positive than that of each corresponding group 4A element. Use the outer electron configurations for these columns to suggest a reason for this behavior.

Ly T.
Numerade Educator

Problem 111

The elements with atomic numbers 35 and 53 have similar chemical properties. Based on their electronic configurations predict the atomic number of a heavier element that also should have these chemical properties.

KC
Kevin C.
Numerade Educator

Problem 112

Write the electronic configurations of the six cations that form from sulfur by the loss of one to six electrons. For those cations that have unpaired electrons, write orbital diagrams.

Ly T.
Numerade Educator

Problem 113

You have cracked a secret code that uses elemental symbols to spell words. The code uses numbers to designate the elemental symbols. Each number is the sum of the atomic number and the highest principal quantum number of the highest occupied orbital of the element whose symbol is to be used.
Messages may be written forward or backward. Decode the following messages:

a. 10, 12, 58, 11, 7, 44, 63, 66
b. 9, 99, 30, 95, 19, 47, 79

KC
Kevin C.
Numerade Educator

Problem 114

The electron affinity of sodium is lower than that of lithium, while the electron affinity of chlorine is higher than that of fluorine. Suggest an explanation for this observation.

Check back soon!

Problem 115

Use Coulomb"s law to calculate the ionization energy in kJ>mol of an atom composed of a proton and an electron separated by 100.00 pm. What wavelength of light would have sufficient energy to ionize the atom?

Ly T.
Numerade Educator

Problem 116

The first ionization energy of sodium is 496 kJ>mol. Use Coulomb"s law to estimate the average distance between the sodium nucleus and the 3s electron. How does this distance compare to the atomic radius of sodium? Explain the difference.

Ly T.
Numerade Educator

Problem 117

Consider the densities and atomic radii of the noble gases at 25 C:

a. Estimate the densities of argon and xenon by interpolation from the data.
b. Provide an estimate of the density of the yet undiscovered element with atomic number 118 by extrapolation from the data.
c. Use the molar mass of neon to estimate the mass of a neon atom. Then use the atomic radius of neon to calculate the average density of a neon atom. How does this density compare to the density of neon gas? What does this comparison suggest about the nature of neon gas?
d. Use the densities and molar masses of krypton and neon to calculate the number of atoms of each element found in a volume of 1.0 L. Use these values to estimate the number of atoms that occur in 1.0 L of Ar. Now use the molar mass of argon to estimate the density of Ar. How does this estimate compare to that in part a?

Ly T.
Numerade Educator

Problem 118

As you have seen, the periodic table is a result of empirical observation (i.e., the periodic law), but quantum-mechanical theory explains why the table is so arranged. Suppose that, in another universe, quantum theory was such that there were one s orbital but only two p orbitals (instead of three) and only three d orbitals (instead of five). Draw out the first four periods of the periodic table in this alternative universe. Which elements would be the equivalent of the noble gases? Halogens? Alkali metals?

Ly T.
Numerade Educator

Problem 119

Consider the metals in the first transition series. Use periodic trends to predict a trend in density as we move to the right across the series.

Charotte M.
Numerade Educator

Problem 120

Imagine a universe in which the value of ms can be +12, 0, and -12. Assuming that all the other quantum numbers can take only the values possible in our world and that the Pauli exclusion principle
applies, determine:

a. the new electronic configuration of neon
b. the atomic number of the element with a completed n = 2 shell
c. the number of unpaired electrons in fluorine

Ly T.
Numerade Educator

Problem 121

A carbon atom can absorb radiation of various wavelengths with resulting changes in its electronic configuration. Write orbital diagrams for the electronic configurations of carbon that result from absorption of the three longest wavelengths of radiation that change its electronic configuration.

Jennifer H.
Numerade Educator

Problem 122

Only trace amounts of the synthetic element darmstadtium, atomic number 110, have been obtained. The element is so highly unstable that no observations of its properties have been possible. Based on its position in the periodic table, propose three different reasonable valence electron configurations for this
element.

Ly T.
Numerade Educator

Problem 123

What is the atomic number of the as yet undiscovered element in which the 8s and 8p electron energy levels fill? Predict the chemical behavior of this element.

KC
Kevin C.
Numerade Educator

Problem 124

The trend in second ionization energy for the elements from lithium to fluorine is not a regular one. Predict which of these elements has the highest second ionization energy and which has the lowest and explain. Of the elements N, O, and F, O has the highest and N the lowest second ionization energy. Explain.

Ly T.
Numerade Educator

Problem 125

Unlike the elements in groups 1A and 2A, those in group 3A do not show a regular decrease in first ionization energy in going down the column. Explain the irregularities.

KC
Kevin C.
Numerade Educator

Problem 126

Using the data in Figures 3.19 and 3.20, calculate E (the change in energy) for the reaction

Ly T.
Numerade Educator

Problem 127

Even though adding two electrons to O or S forms an ion with a noble gas electron configuration, the second electron affinity of both of these elements is positive. Explain.

KC
Kevin C.
Numerade Educator

Problem 128

In Section 3.5 we discussed the metalloids, which form a diagonal band separating the metals from the nonmetals. There are other instances in which elements such as lithium and magnesium that are diagonal to each other have comparable metallic character. Suggest an explanation for this observation.

Jorge V.
Numerade Educator

Problem 129

The heaviest known alkaline earth metal is radium, atomic number 88. Find the atomic numbers of the as yet undiscovered next two members of the series.

KC
Kevin C.
Numerade Educator

Problem 130

Predict the electronic configurations of the first two excited states (next higher energy states beyond the ground state) of Pd.

Ly T.
Numerade Educator

Problem 131

Imagine that in another universe, atoms and elements are identical to ours, except that atoms with six valence electrons have particular stability (in contrast to our universe where atoms with eight valence electrons have particular stability). Give an example of an element in the alternative universe that corresponds to:

a. a noble gas
b. a reactive nonmetal
c. a reactive metal

Charotte M.
Numerade Educator

Problem 132

The outermost valence electron in atom A experiences an effective nuclear charge of 2+ and is on average 225 pm from the nucleus. The outermost valence electron in atom B experiences an effective nuclear charge of 1+ and is on average 175 pm from the nucleus. Which atom (A or B) has the higher first ionization energy? Explain.

Ronald P.
Numerade Educator

Problem 133

Determine whether each statement regarding penetration and shielding is true or false. (Assume that all lower energy orbitals are fully occupied.)

a. An electron in a 3s orbital is more shielded than an electron in a 2s orbital.
b. An electron in a 3s orbital penetrates into the region occupied by core electrons more than electrons in a 3p orbital.
c. An electron in an orbital that penetrates closer to the nucleus will always experience more shielding than an electron in an orbital that does not penetrate as far.
d. An electron in an orbital that penetrates close to the nucleus will tend to experience a higher effective nuclear charge than one that does not.

KC
Kevin C.
Numerade Educator

Problem 134

Give a combination of four quantum numbers that could be assigned to an electron occupying a 5p orbital. Do the same for an electron occupying a 6d orbital.

David C.
Numerade Educator

Problem 135

Use the trends in ionization energy and electron affinity to explain why calcium fluoride has the formula CaF2 and not Ca2F or CaF.

Charotte M.
Numerade Educator

Problem 136

In a complete sentence, describe the relationship between shielding and penetration.

Check back soon!

Problem 137

Play a game to memorize the order in which orbitals fill. Have each group member in turn state the name of the next orbital to fill and the maximum number of electrons it can hold (for example, '1s two,' 2s two,' '2p six'). If a member gets stuck, other group members can help, consulting Figure 3.8 and the
accompanying text summary if necessary. However, when a member gets stuck, the next player starts back at '1s two.' Keep going until each group member can list all the orbitals in order up to '6s two.'

Jorge V.
Numerade Educator

Problem 138

Sketch a periodic table (without element symbols). Include the correct number of rows and columns in the s, p, d, and f blocks. Shade in the squares for elements that have irregular electron configurations.

Lyniesha W.
Numerade Educator

Problem 139

In complete sentences, explain: a) why Se2- and Br- are about the same size; b) why Br- is slightly smaller than Se2-; and c) which singly charged cation you would expect to be approximately the
same size as Se2- and Br- and why.

KC
Kevin C.
Numerade Educator

Problem 140

Have each member of your group sketch a periodic table indicating a periodic trend (atomic size, first ionization energy, metallic character, etc.). Have each member present his or her table to the
rest of the group and explain the trend based on concepts such as orbital size or effective nuclear charge.

Lyniesha W.
Numerade Educator

Problem 141

The following graphs show the first ionization energies and electron affinities of the period 3 elements. Refer to the graphs to answer the questions that follow.

a. Describe the general trend in period 3 first ionization energies as you move from left to right across the periodic table. Explain why this trend occurs.
b. The trend in first ionization energy has two exceptions: one at Al and another S. Explain why the first ionization energy of Al is lower than that of Mg and why the first ionization of S is less than that of P.
c. Describe the general trend in period 3 electron affinities as you move from left to right across the periodic table. Explain why this trend occurs.
d. The trend in electron affinities has exceptions at Mg and P. Explain why the electron affinity of Mg is more positive (less exothermic) than that of Na and why the electron affinity of P is more positive (less exothermic) than that of Si.
e. Determine the overall energy change for removing one electron from Na and adding that electron to Cl. Is the exchange of the electron exothermic or endothermic?

Check back soon!