Chapter 17: Elements And Their Properties

Atoms have no electric charge because they

C. have an equal number of electrons and protons.

The order of elements in the periodic table is based on

A. the number of protons in the nucleus.

Atoms of elements that are in the same group have the same number of

C. valence electrons.

Ionization refers to the process of

d. losing or gaining electrons.

A lithium ion is much less reactive than a lithium atom because it

b. has a full outermost energy level.

Which statement about the alkali metals is correct?

a. They are located in the left-most column of the periodic table.

Which of the following elements is an alkali metal?

D. sodium

Alkali metals are extremely reactive because they

c. have one valence electron that is easily removed to form a positive ion.

Which statement about noble gases is correct?

B. They exist as single atoms rather than as molecules.

Semiconductors are elements that

c. can conduct heat and electricity under certain conditions

Most halogens form compounds by

a. gaining an electron to form a negative ion.

Group 18 noble gases are inert because

d. their outermost energy level is full

Carbon and other nonmetals are found in which area of the periodic table?

b. on the right side

Transition metals such as copper or tungsten form compounds by

b. losing electrons to form positive ions.

If the atomic mass of carbon is 12 amu, 1 mole of pure carbon will have a mass of

c. 12 g.

Molar mass is defined as

D. the mass in grains of 1 mole of a substance.

The average atomic mass of potassium is approximately 39 amu. What is the mass of 2.0 mol of potassium.

D. 78 g

The average atomic mass of the element cesium is approximately 133 amu, What is the mass of 3.00 mol of cesium

D. 399 g

In a periodic table, a set of properties repeats from

d. row to row.

Which list of elements contains only metals?

b. tin, copper, cesium

Which statement is true about the metalloid silicon?

d. Silicon is a better conductor of electric current than sulfur is

At room temperature, none of the metals are

d. gases.

Which general statement does NOT apply to metals?

c. Most metals are brittle.

Two highly reactive elements in Period 2 are the metal lithium and the

C. nonmetal fluorine.

Atoms of the most reactive elements tend to have

a. one or seven valence electrons.

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

A. increases.

Which statement is NOT true about the elements fluorine, chlorine, and iodine?

C. They are similar to noble gases.

Which of the following gases emit colors when an electric current is applied?

b. argon and krypton

To keep then from reacting, some highly reactive elements are stored in

d. argon.

Which element is found in nature only in compounds?

A. sodium

Which element is found in most of the compounds in your body except for water?

d. carbon

The forces that hold different atoms or ions together are

b. chemical bonds.

A mixture is different from a compound because each substance in a mixture

A. Retains its own properties.

A compound differs from a mixture because it

c. always contains the same elements in the same proportion.

Each molecule of table sugar, C12H22O11, contains

D. 12 atoms of carbon

Which compound is formed from a tight network of oppositely charged ions?

D. salt, NaCI

In which substance do the molecules have the strongest attractions to one another?

A. sugar, a solid

Often atoms join so that each atom will have

B. an outermost energy level that is full of electrons.

When two hydrogen atoms bond, the positive nucleus of one atom attracts the

C. negative electron of the other atom.

An ionic bond is a bond that forms between

A. ions with opposite charges.

Covalent bonds are formed between

C. nonmetal atoms.

In a metallic bond, the nucleus of one atom is attracted by a nearby atom's

D. Electrons

Copper is a good conductor of electricity because its electrons

B. are free to move from atom to atom.

Solid ionic compounds have very high melting points because they

d. contain charged ions that are locked tightly together.

In which type of bond do atoms share electrons?

A. Covalent Bonds

What do the whole numbers on the periodic table represent?

Atomic Number

Selenium has six valence electrons, while rubidium has one valence electron, Identify each element as a metal or a nonmetal.

Rubidium is a metal / Selenium is a nonmetal

On the periodic table, there are two numbers in the block for the element potassium, K: 19 and 39.098. What are these two numbers and what do they represent?

19 = Atomic Number 39.098 = Atomic Mass

Period 5 of the periodic table begins with element 37 and ends with element 54. Consider the following elements from row 5: strontium (element 38), cadmium (element 48), and iodine (element 53). Which of
these elements is most likely to be a transition metal?

Cadmium

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

Sodium = Alkali
Chlorine = Halogen