Standard: 1cArticles: 160Mastering Concepts: 174 (41-53)Practice Problems: 162(7-9)HomeworkCornell Notes: 6.2Section Assessment: 162 (10-13)Labs: 170

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Section 6-2Section 6.2 Classification of the Elements

Explain why elements in the same group have similar properties.

valence electron: electron in an atom's outermost orbitals; determines the chemical properties of an atomIdentify the four blocks of

the periodic table based on their electron configuration.

Elements are organized into different blocks in the periodic table according to their electron configurations.

Section 6-2Organizing the Elements by Electron Configuration

Recall electrons in the highest principal energy level are called valence electrons.

All group 1 elements have one valence electron.

Section 6-2Organizing the Elements by Electron Configuration (cont.)

The energy level of an element’s valence electrons indicates the period on the periodic table in which it is found.

The number of valence electrons for elements in groups 13-18 is ten less than their group number.

Section 6-2Organizing the Elements by Electron Configuration (cont.)

Section 6-2The s-, p-, d-, and f-Block Elements

The shape of the periodic table becomes clear if it is divided into blocks representing the atom’s energy sublevel being filled with valence electrons.

Section 6-2The s-, p-, d-, and f-Block Elements (cont.)

s-block elements consist of group 1 and 2, and the element helium.

Group 1 elements have a partially filled s orbital with one electron.

Group 2 elements have a completely filled s orbital with two electrons.

Section 6-2The s-, p-, d-, and f-Block Elements (cont.)

After the s-orbital is filled, valence electrons occupy the p-orbital.

Groups 13-18 contain elements with completely or partially filled p orbitals.

Section 6-2The s-, p-, d-, and f-Block Elements (cont.)

The d-block contains the transition metals and is the largest block.

There are exceptions, but d-block elements usually have filled outermost s orbital, and filled or partially filled d orbital.

The five d orbitals can hold 10 electrons, so the d-block spans ten groups on the periodic table.

Section 6-2The s-, p-, d-, and f-Block Elements (cont.)

The f-block contains the inner transition metals.

f-block elements have filled or partially filled outermost s orbitals and filled or partially filled 4f and 5f orbitals.

The 7 f orbitals hold 14 electrons, and the inner transition metals span 14 groups.

Standard: 1cArticles: 160Mastering Concepts: 174 (41-50)Practice Problems: 162(7-9)HomeworkCornell Notes: 6.2Section Assessment: 162 (10-13)Labs: 170

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Mastering Concepts: 174 (41-50)

41. Why do the elements chlorine and iodine have similar chemical properties? (6.2)

They have the same valence electron configuration (s2p5 ).

Mastering Concepts: 174 (41-50)

42. How are the numbers of valence electrons of the group A elements related to the group number? (6.2)

The number of valence electrons equals the group number for group A elements.

43. How is the energy level of an atom’s valence electrons related to the period it is in on the periodic table? (6.2)

The energy level of an atom’s valence electrons equals its period number.

Mastering Concepts: 174 (41-50)

44. How many valence electrons do each of the noble gases have? (6.2)

All noble gases have eight valence electrons, except for helium, which has two.

Mastering Concepts: 174 (41-50)

45. What are the four blocks of the periodic table? (6.2)

s-, p-, d-, and f-block

46. In general, what electron configuration has the greatest stability? (6.2)

ns2np6, where n is the energy level

Mastering Concepts: 174 (41-50)

Mastering Concepts: 174 (41-50)

47. Determine the group, period, and block in which each of the following elements is located on the periodic table. (6.2)

a.[Kr]5s24d1

18

a.[Kr]5s24d1 [Kr] =36

s

f

d

pPeriod

Group3B

the group, period, and block

47.a.Group:3B, period 5, d-block

Mastering Concepts: 174 (41-53)

Mastering Concepts: 174 (41-50)

47. Determine the group, period, and block in which each of the following elements is located on the periodic table. (6.2)

b. [Ar]4s23d104p3

21

[Ar]4s23d104p3

[Ar] =18

s

f

d pPeriod

Group5A

the group, period, and block

[18+2+10+3=33

47.

b. Group-5A,

period 4,

p-block

Mastering Concepts: 174 (41-50)

Mastering Concepts: 174 (41-50)

47. Determine the group, period, and block in which each of the following elements is located on the periodic table. (6.2)

c. [He]2s22p6

24

[He]2s22p6

[He] =2

s

f

d pPeriod

Group8A

the group, period, and block

[2+2+6=10

47.

c. Group-8A,

period 2,

p-block

Mastering Concepts: 174 (41-50)

Mastering Concepts: 174 (41-50)

47. Determine the group, period, and block in which each of the following elements is located on the periodic table. (6.2)

d. [Ne]3s23p1

27

[Ne]3s23p1

[Ne] =10

s

f

d pPeriod

Group3A

the group, period, and block

[10+2+1=13

47.

d. Group-3A,

period 3,

p-block

Mastering Concepts: 174 (41-50)

48. Categorize each of the elements in problem 47 as a representative element or a transition metal. (6.2)

Mastering Concepts: 174 (41-50)

30

a.[Kr]5s24d1 [Kr] =36

Representative or transition

[36+2+1=39

Representative or transition

48. Categorize each of the as a representative element or a transition metal. (6.2)

a.[Kr]5s24d1

transition element

Mastering Concepts: 174 (41-50)

32

[Ar]4s23d104p3

[Ar] =18

[18+2+10+3=33

Representative or transition

Representative or transition

48.

b. [Ar]4s23d104p3

representative element

Mastering Concepts: 174 (41-50)

34

[He]2s22p6

[He] =2

[2+2+6=10

Representative or transition

Representative or transition

48.

c. [He]2s22p6

representative element

Mastering Concepts: 174 (41-50)

36

[Ne]3s23p1

[Ne] =10

[10+2+1=13

Representative or transition

Representative or transition

48.

d. [Ne]3s23p1

representative element

Mastering Concepts: 174 (41-50)

Mastering Concepts: 174 (41-50)

49. Explain how an atom’s valence electron configuration determines its place on the periodic table. (6.2)

Elements in a given column have the same number of valence electrons. The energy level of an atom’s valence electrons determines its period.

Mastering Concepts: 174 (41-50)

50. Write the electron configuration for the element fitting each of the following descriptions. (6.2)

40

6s

5d

6p

the metal in group 5A

Noble gas=Xe

4f

Mastering Concepts: 174 (41-50)

50.

a. the metal in group 5A

Bi:

[Xe]6s24f145d106p3

42

3s 3p

b. the halogen in period 3Noble gas=Ne

Mastering Concepts: 174 (41-50)

50.

b. the halogen in period 3

Cl:

[Ne]3s23p5

44

2s

c. the alkali metal in period 2

Mastering Concepts: 174 (41-50)

50. c. the alkali metal in period 2

Li : [He]2s1

46

6s

5d

transition metal that is a liquid at room temperature

Noble gas=Xe

4f

Mastering Concepts: 174 (41-50)

50. d. the transition metal that is a liquid at room temperature

Hg:

[Xe]6s24f145d10

Standard: 1cArticles: 160Mastering Concepts: 174 (41-53)Cornell Notes: 6.2Section Assessment: 162 (10-13)Labs: 170Practice Problems: 162(7-9)

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Practice Problems: 162(7-9)7. Without using the periodic table, determine the group, period, and block of an atom with the following electron configurations.

a. [Ne]3s2

b. [He]2s2

c. [Kr]5s24d105p5

7. Electron

configuration Group Period Block

a.[Ne]3s2 2A 3s

7. Electron

configuration Group Period Block

b. [He]2s2 2A 2s

7. Electron

configuration Group Period Block

c. [Kr]5s24d105p5 7A 5 p

Practice Problems: 162(7-9)

8. Write the electron configuration of the element fitting each of the following descriptions.

a. The group 2A element in the fourth period

b. The noble gas in the fifth period

c. The group 2B element in the fourth period

d. The group 6A element in the second period

Practice Problems: 162(7-9)

8. Write the electron configuration of the element fitting each of the following descriptions.

a. The group 2A element in the fourth period

[Ar]4s2

Practice Problems: 162(7-9)

8. Write the electron configuration of the element fitting each of the following descriptions.

b. The noble gas in the fifth period

[Xe]

Practice Problems: 162(7-9)

8. Write the electron configuration of the element fitting each of the following descriptions.

c. The group 2B element in the fourth period

[Ar]4s23d10

Practice Problems: 162(7-9)

8. Write the electron configuration of the element fitting each of the following descriptions.

d. The group 6A element in the second period

[He]2s22p4

Practice Problems: 162(7-9)

9. What are the symbols for the elements with the following valence electron configurations?

a. s2d1

Sc, Y, La, Acb. s2p3

b. N, P, As, Sb, Bi

c. s2p6

c. Ne, Ar, Kr, Xe, Rn