homeworkchapter05.htmlTEXTsfriR灁. F.J. DeHoratius Chapter 5 Homework Mod Chem

Chapter 5 - Homework
The Periodic Law


5.1 History of the Periodic Table

1. a) Who is credited with developing a method that led to the determination of standard relative atomic masses?
b) Who discovered the periodic law?
c) Who established atomic numbers as the basis for organizing the periodic table?

2. Name three sets of elements added to the periodic table after Mendeleev's time.

3. How is the periodic law demonstrated within the groups of the periodic table?

5.2 Electron Configuration and the Periodic Table

1. Without looking at the periodic table, give the group,period, and block in which the element with the electron configuration [Kr]5s2 is located.

2. a) Without looking at the periodic table, write the group configuration for the Group 2 elements.
b) Without looking at the periodic table,write the complete electron configuration for the Group 2 element in the fourth period.
c) Refer to Figure 5-6 to identify the element described in (b) above. Then write the element's noble gas notation.
d) How does the reactivity of the element in (b) compare with the reactivity of the element in Group 1 of the same period?

3. Without looking at the periodic table, identify the period, block, and group in which the element with the electron configuration [Ar]4s2 3d8 is located.

4. a) Without looking at the periodic table, write the outer group electron configuration for the Group 12 element in the fifth period.
b) Refer to the periodic table to identify the element described in (a) and to write the element's noble gas notation.

5. a) Without looking at the periodic table, write the outer electron configuration for the Group 17 element in the third period.
b) Name the element described in (a), and identify it as a metal, nonmetal, or metalloid.

6. a) Without looking at the periodic table, identify the period, block, and group of an element with the electron configuration [Ar]4s2 3d10 4p3.
b) Name the element described in (a), and identify it as a metal, nonmetal,or metalloid.

7. Into what four blocks can the periodic table be divided to illustrate the relationship between the elements' electron configurations and their placement in the periodic table?

8. What name is given to each of the following groups of elements on the periodic table:
a) Group 1
b) Group 2
c) Groups 3-12
d) Group 17
e) Group 18

9. What are the relationships between group configuration and group number for elements in the s, p, and d blocks?

10. How do the electron configurations within the same group of elements compare?

11. What is the relationship between the electron configuration of an element and the period in which that element appears in the periodic table?

12. List four characteristic properties of alkali metals.

13. How do the properties of alkali metals compare with the alkaline earth metals?

14. Which are the main group elements?

5.3 Electron Configuration and Periodic Properties

1. Of the elements Li, O, C and F, identify the one with the largest atomic radius and the one with the smallest atomic radius.

2. Of the elements Br, At, F, I and Cl, identify the one with the smallest atomic radius and the one with the largest atomic radius.

3. Consider the four hypothetical main group elements Q, R, T and X with the outer electron configurations indicated below. Then answer the questions that follow.
Q: 3s2 3p5
R: 3s1
T: 5s2 4d10 5p5
X: 5s2 4d10 5p1

4. a) Identify the block location of each hypothetical main group element.
b) Which of these elements are in the same period?
c) Which of these elements are in the same group?
d) Which element would you expect to have the highest first ionization energy?
e) Which element would have the lowest first ionization energy?
f) Which element would you expect to have the highest second ionization energy?
g) Which of the elements is most likely to form a 1+ ion?

5. Consider the five hypothetical main group element E, G, J, L and M with the outer electron configurations shown below.
E: 2s2 2p5
G: 5s2 4d10 5p5
J: 2s2 2p2
L: 6s2 5d10 6p5
M: 2s2 2p4

6. a) Identify the block location for each element.
b) Indicate which elements are in the same period.
c) Indicate which elements are in the same group.
d) Which element would you expect to have the highest electron affinity?
e) Which would you expect to from a 1- ion?
f) Which should have the highest electronegativity?
g) Compare the ionic radius of the typical ion formed by the element G with the radius of its neutral atom.
h) Which element(s) contains seven valence electrons?

7. State the general period and group trends among main group elements with respect to each of the following properties:
a) atomic radii
b) first ionization energy
c) electron affinity
d) ionic radii
e) electronegativity

8. Among the main group elements, what is the relationship between group number and the number of valence electrons among group members?

9. a) How do the first ionization energies of main group elements vary across a period and down a group?
b) Explain the basis for the trends.

10. a) What signs are associated with electron affinity values, and
b) What is the significance of each sign?

11. For each of the following groups, indicate whether electrons are more likely to be lost or gained in compound formation and give the number of such electrons typically involved:
a) Group 1
b) Group 2
c) Group 13
d) Group 16
e) Group 17
f) Group 18

12. Why is fluorine special in terms of electronegativity?