Chapter 6

Describe the development of the modern periodic table. Include contributions made by Lavoisier, Newlands, Mendeleev, and Moseley.

Describe the general characteristics of metals, nonmetals, and metalloids.

Identify each of the following as a representative element or a transition element. a. lithium (Li) b. platinum (Pt) c. promethium (Pm) d. carbon (C)

Compare For each of the given elements, list two other elements with similar chemical properties a. iodine (I) b. barium (Ba) c. iron (Fe)

Interpret Data A company plans to make an electronic device. They need to use an element that has chemical behavior similar to that of silicon (Si) and lead (Pb). The element must have an atomic mass greater than that of sulfur (S), but less than that of cadmium (Cd). Use the periodic table to determine which element the company could use.

Without using the periodic table, determine the group, period, and block of an atom with the following electron configurations a. \([\mathrm{Ne}] 3 \mathrm{s}^{2}\) b. \([\text { He }] 2 s^{2}\) c. \([\mathrm{Kr}] 5 s^{2} 4 \mathrm{d}^{10} 5 p^{5}\)

Challenge Write the electron configuration of the following elements. a. the group 2 element in the fourth period b. the group 12 element in the fourth period c. the noble gas in the fifth period d. the group 16 element in the second period

Determine in which block of the periodic table are the elements having the following valence electron configurations. a. \(s^{2} p^{4}\) b. \(s^{1}\) c. \(s^{2} d^{1}\) \(\mathrm{d} . \mathrm{s}^{2} \mathrm{p}^{1}\)

Infer Xenon, a nonreactive gas used in strobe lights, is a poor conductor of heat and electricity. Would you expect xenon to be a metal, a nonmetal, or a metalloid? Where would you expect it to be on the periodic table? Explain.

Explain why elements within a group have similar chemical properties.

Model Make a simplified sketch of the periodic table, and label the s-, p-, d-, and f-blocks.

Which has the largest atomic radius: magnesium (Mg), silicon (Si), sulfur (S), or sodium (Na)? The smallest?

Can you determine which of two unknown elements has the larger radius if the only known information is that the atomic number of one of the elements is 20 greater than the other? Explain.

Challenge Determine which element in each pair has the largest atomic radius: a. the element in period \(2,\) group \(1 ;\) or the element in period \(3,\) group 18 b. the element in period \(5,\) group \(2 ;\) or the element in period \(3,\) group 16 c. the element in period \(3,\) group \(14 ;\) or the element in period \(6,\) group 15 d. the element in period \(4,\) group \(18 ;\) or the element in period \(2,\) group 16

Explain how the period and group trends in atomic radii are related to electron configuration

Indicate whether fluorine or bromine has a larger value for each of the following properties. \(\begin{array}{ll}{\text { a. electronegativity }} & {\text { c. atomic radius }} \\ {\text { b. ionic radius }} & {\text { d. ionization energy }}\end{array}\)

Explain why it takes more energy to remove the second electron from a lithium atom than it does to remove the fourth electron from a carbon atom

Calculate Determine the differences in electronegativity, ionic radius, atomic radius, and first ionization energy for oxygen and beryllium.

Make and Use Graphs Graph the atomic radii of the representative elements in periods 2, 3, and 4 versus their atomic numbers. Connect the points of elements in each period, so that there are three separate curves on the graph. Summarize the trends in atomic radii shown on your graph. Explain.

Explain the contribution of Newlands’s law of octaves to the development of the modern periodic table

Lothar Meyer and Dmitri Mendeleev both proposed similar periodic tables in 1869. Why is Mendeleev generally given credit for the periodic table

What is the periodic law?

Describe the general characteristics of metals

Describe the general characteristics of metals

Identify each of the following as a metal, a nonmetal, \(\begin{array}{ll}{\text { a. oxygen }} & {\text { c. germanium }} \\ {\text { b. barium }} & {\text { d. iron }}\end{array}\)

Match each item on the left with its corresponding group on the right. $$ \begin{array}{ll}{\text { a. alkali metals }} & {\text { 1. group } 18} \\\ {\text { b. halogens }} & {\text { 2. group } 1}\end{array} $$ $$ \begin{array}{ll}{\text { c. alkaline earth metals }} & {\text { 3. group } 2} \\\ {\text { d. noble gases }} & {\text { 4. group } 17}\end{array} $$

Sketch a simplified periodic table, and use labels to identify the alkali metals, alkaline earth metals, transition metals, inner transition metals, noble gases, and halogens.

Give the chemical symbol of each of the following elements. a. a metal used in thermometers b. a radioactive gas used to predict earthquakes; the noble gas with the greatest atomic mass c. a coating for food cans; it is the metal in group 14 with the lowest atomic mass d. an inner transition metal that is used to make burglar-proof vaults; also the name of a coin

New Heavy Element If scientists discovered an element with 117 protons, what would be the its group and period? Would it be a metal, a metalloid, or a nonmetal?

Give the chemical symbol for each element. a. the element in period 3 that can be used in making computer chips because it is a metalloid b. the group \(13,\) period 5 metal used in making flat screens for televisions c. an element used as a filament in lightbulbs; has the highest atomic mass natural elements in group 6

Household Products Why do the elements chlorine, used in laundry bleach, and iodine, a nutrient added to table salt, have similar chemical properties?

How is the energy level of an atom’s valence electrons related to its period in the periodic table?

How many valence electrons does each noble gas have?

What are the four blocks of the periodic table?

Explain how an atom’s valence electron configuration determines its place in the periodic table.

Write the electron configuration for the element fitting each of the following descriptions. a. the metal in group 15 that is part of compounds often found in cosmetics b. the halogen in period 3 that is part of a bleaching compound used in paper production c. the transition metal that is a liquid at room temperature; is sometimes used in outdoor security lights

Determine the group, period, and block in which each of the following elements is located in the periodic table. a. \([\mathrm{Kr}] 5 s 2^{4} \mathrm{d}^{1}\) b. \([\mathrm{Ar}] 4 \mathrm{s}^{2} 3 \mathrm{d}^{10} 4 \mathrm{p}^{3}\) c. \([\mathrm{He}] 2 \mathrm{s}^{2} 2 \mathrm{p}^{6}\) d. \([\mathrm{Ne}] 3 s^{2} 3 \mathrm{p}^{1}\)

Table 6.7 shows the number of elements in the first five periods of the periodic table. Explain why some of the periods have different numbers of elements

Coins One of the transition groups is often called the coinage group because at one time many coins are made of these metals. Which group is this? What elements in this group is still used in many U.S. coins today?

Do any of the halogens have their valence electrons in orbitals of the same energy level? Explain

The transition elements have their valence electrons in orbitals of more than one energy level, but the representative elements have their valence electrons in orbitals of only one energy level. Show this by using the electron configurations of a transition element and a representative element as examples.

Fireworks Barium is a metal that gives a green color to fireworks. Write the electron configuration for barium. Classify it according to group, period, and block in the periodic table

Headphones Neodymium magnets can be used in stereo headphones because they are powerful and lightweight. Write the electron configuration for neodymium. In which block of the periodic table is it?

Soda Cans The metal used to make soda cans has the electron configuration \([\mathrm{Ne}] 3 \mathrm{s}^{2} 3 \mathrm{p}^{1}\) . Identify the metal and give its group, period, and block.

An element forms a negative ion when ionized. On what side of the periodic table is the element located? Explain.

Of the elements magnesium, calcium, and barium, which forms the ion with the largest radius? The smallest? What periodic trend explains this?

Explain why each successive ionization of an electron requires a greater amount of energy.

How does the ionic radius of a nonmetal compare with its atomic radius? Explain the change in radius.

Explain why atomic radii decrease as you move from left to right across a period.

Which element has the larger ionization energy? a. Li,N \(\quad\) b. Kr, Ne \(\quad\) c. \(\mathrm{Cs},\) Li