Chapter 5 -- The Periodic Table

Hydrogen does not have the typical physical properties of a metal. However, hydrogen is located above Group 1A because it has one ____________ _____________.

valence electron

Elements are put together in the same group because they have the same number of ___________.

valence electrons

Refer to Graphics Handout. Find the block labeled " ? " in Figure 5-2. How many valence electrons does it have?

2

A member of the boron family has 3 valence electrons, while a member of the nitrogen family has

5 valence electrons

Refer to Graphics Handout. Figure 5-1 shows a portion of a blank periodic table. What do we call the segments labeled A and B ?

A is a period and B is a group.

Refer to Graphics Handout. Which group of four elements shown in Figure 5-2 is in the same period?

Be, C, N, and F

Refer to Graphics Handout. Find the block labeled " ? " in Figure 5-2. Which of the elements shown in Figure 5-2 will it most resemble in chemical reactions?

Beryllium

Refer to Graphics Handout. Which element does the planetary model represent? a. b. c. d.

Carbon

Element X has five valence electrons, element Y has one valence electron, and element Z has five valence electrons. Which two of these elements are most likely to have similar chemical properties? Explain your answer.

Elements X and Z will have similar properties because they have the same number of valence electrons.

Refer to Graphics Handout. Which elements in Figure 5-2 have the same number of valence electrons? How do you know?

F and I; they are in the same group in the periodic table.

Selenium has six valence electrons, while rubidium has one valence electron. Without looking at a periodic table, identify each element as a metal or a nonmetal. How do you know?

Rubidium has 1 VE (left side of PT) so it is a metal. Selenium has 6 VE (right side of PT) so it is a nonmetal.

Sodium chloride is a compound of sodium and chlorine. Which of these elements is the alkali metal, and which is the halogen?

Sodium is the alkali metal, and chlorine is the halogen.

Refer to Graphics Handout. Without looking at a periodic table, are the elements in Figure 5-3 metals, metalloids, or nonmetals? How do you know?

These elements are all metals. The group numbers tell us that they are from the left side of the Periodic Table.

Which statement is NOT true about the elements fluorine, chlorine, and iodine? a. They are all halogens. b. They are all in Group 17 c. They have properties similar to noble gases. d. They are all nonmetals.

They have properties similar to noble gases

Refer to Graphics Handout. Which element in Figure 5-2 is a transition metal?

Vanadium

Suppose you are looking at elements in the periodic table in this order: element 23, element 24, element 25, element 26, and so on. Are you looking across a period or down a group? Explain your answer.

across a period because the atomic number is increasing by one each time

Period 5 begins with element 37 and ends with element 54. Consider strontium (#38), cadmium (#48), and iodine (#53). Without looking at a periodic table, which of these elements is most likely to be a transition metal? How do you know?

cadmium Transitions metals are in the middle of the periodic table, and # 48 is between # 38 and # 53

Refer to Graphics Handout. Suppose scientists discovered four new elements (W, X, Y, Z) while studying rock and soil samples brought back from a Mars mission. Which dot structure represents an element that should be placed in column 17 of the periodic table? a. b. c. d.

d

Elements are put together in the same period because they have the same number of ___________.

energy levels of electrons

As you move from left to right across a period, the number of valence electrons

increases

Boron (B), silicon (Si), germanium (Ge), and arsenic (As) are elements that have properties that fall between those of metals and nonmetals. What common label could you apply to these elements?

metalloids

Elements can be classified as metals, nonmetals, and ____________________.

metalloids

Compared with Group 2 elements, Group 16 elements have a. more atoms in the ground state. b. more valence electrons. c. more isotopes. d. fewer valence electrons.

more valence electrons.

Which list of elements contains only metals? a. helium, carbon, gold b. sodium, chromium, copper c. iodine, iron, nickel d. phosphorus, nitrogen, oxygen

sodium, chromium, copper

The way an element will react in a chemical reaction is closely related to

the number of valence electrons in atoms of the element.