Deck 3: Compounds and Molecules

Question 1

Below are two charged particles. What will they do when in close proximity to one another?

A) They will do nothing.
B) The particle on the left will transfer its positive charge to the particle on the right.
C) The particle on the right will transfer its negative charge to the particle on the left.
D) They will attract one another.
E) They will repel one another.

Answer 1

They will attract one another.

Question 2

Which of the following ions is a polyatomic ion?

A) NH₄⁺
B) Mg²⁺
C) O^2-
D) O₂
E) C₂H₆

Answer 2

NH₄⁺

Question 3

What is the ionic formula for the ionic compound composed of calcium and chloride?

A) Ca?₂Cl
B) CaCl
C) Ca?₂Cl₂
D) Ca₂Cl₃
E) CaCl₂

Answer 3

CaCl₂

Question 4

The following ionic formula is not valid. Which of the following statements best describes what's wrong with this formula? AlCl₂

A) It does not include both a nonmetal and a metal.
B) The ratio of cations to anions is not 1:1.
C) The anion is written first, followed by the cation.
D) This compound does not exist in nature.
E) The charges do not add up to zero.

Question 5

In an ionic compound,

A) nonmetals share electrons.
B) nonmetals donate electrons to metals.
C) metals are attracted to one another.
D) metals share electrons.
E) cations and anions are attracted to one another.

Question 6

What ionic compound has the formula Na₂O?

A) disodium oxide
B) sodium oxide
C) sodium dioxide
D) sodium oxygen
E) disodium oxygen

Question 7

Nonmetals typically ______ and metals typically ______.

A) donate electrons; accept electrons
B) accept electrons; donate electrons
C) donate protons; accept protons
D) accept protons; donate protons
E) donate neutrons; accept neutrons

Question 8

Magnesium chloride is sometimes administered orally to suppress premature labor. Which of the following is a valid ionic formula for magnesium chloride?

A) Mg₂Cl₂
B) Mg₂Cl
C) MgCl
D) MgCl₂
E) None of the above choices are magnesium chloride.

Question 9

What is the charge on each chlorine in an ionic compound composed of calcium and chlorine?

A) +1
B) (-1)
C) +2
D) (-2)
E) +3

Question 10

What is the meaning of the symbol below? [PO₄]^3-

A) The phosphorous has three more electrons than protons.
B) Three oxygens each have one more electron than protons.
C) Each of the four oxygens has three more electrons than protons.
D) The ion has three more electrons than protons.
E) The 3- means that the molecule has lost three electrons.

Question 11

Below are two ions (not drawn to scale). What will they do when in close proximity to one another?

A) They will attract one another, forming an ionic compound.
B) They will attract one another, forming a covalent bond.
C) The sodium ion will transfer a proton to chloride.
D) The chloride ion will transfer an electron to sodium.
E) They will do nothing.

Question 12

Calcium carbonate has the formula CaCO₃. What is the charge on the polyatomic carbonate ion?

A) +2
B) +1
C) 0
D) (-1)
E) (-2)

Question 13

Which of the following is not a valid ionic formula?

A) NaF
B) MgO
C) KCl₂
D) CaF₂
E) Na₂O

Question 14

A polyatomic ion

A) has many atoms, one of which has gained or lost electrons.
B) is a molecule that has gained or lost electrons.
C) has many atoms, one of which has gained or lost protons.
D) is a molecule that has gained or lost protons.
E) has many charges.

Question 15

What is the name of the ionic compound that is composed of calcium and chlorine?

A) calcium dichloride
B) dicalcium trichloride
C) dicalcium chloride
D) calcium chloride
E) dicalcium dichloride

Question 16

People on a low salt diet use a potassium chloride substitute for sodium chloride. Which of the following is a valid ionic formula for potassium chloride?

A) NaCl
B) NaCl₂
C) KCl₂
D) KCl
E) K₂Cl

Question 17

An intravenous therapy called Ringer's solutions contains calcium and chloride along with other components. What is the charge on calcium in this ionic compound that forms from calcium and chlorine?

A) +1
B) (-1)
C) +2
D) (-2)
E) +3

Question 18

An important part of writing a formula unit for an ionic compound is to make sure that

A) the charges of the ions add up to zero.
B) there is never more than one type of cation and one type of anion in the formula.
C) the ionic compound actually exists in nature.
D) the anion is written first, followed by the cation.
E) the ratio of cation to anion is 1:1.

Question 19

Which of the following is the formula for an ionic compound called calcium(II) chloride?

A) C(II)Cl
B) Ca(II)Cl
C) Ca₂Cl
D) C₂Cl
E) CaCl₂

Question 20

What is the charge on iron in the ionic compound FeCl₃?

A) +3
B) +1
C) 0
D) (-1)
E) (-3)

Question 21

"Laughing gas" has the formula N₂O. Which of the following is the best name for this compound?

A) nitrogen oxygen
B) nitrogen oxide
C) nitrogen dioxide
D) dinitrogen monoxide
E) nitrogen(II) oxide

Question 22

Which of the following is the best name for the compound SF₆, a potent greenhouse gas?

A) sulfur fluorine
B) sulfur fluoride
C) sulfur hexafluoride
D) sulfur pentafluoride
E) monosulfur fluoride

Question 23

Why does the lattice of Li₂O below show more ions than the formula unit?

A) The formula unit is a ratio of cations and anions, not the absolute number of ions.
B) There is an error in the formula unit.
C) The formula unit is just a way to balance charge; it doesn't mean anything physically.
D) The formula was written before the true structure was determined.
E) The lattice and the formula are unrelated.

Question 24

An ion that has more electrons than protons is a(n) ________.

A) cation
B) anion
C) ionic bond
D) covalent bond
E) salt

Question 25

Electrons shared between two atoms is a(n) _______.

A) cation
B) anion
C) ionic bond
D) covalent bond
E) salt

Question 26

What is the name of CS₂, an industrial solvent?

A) carbon sulfite
B) carbon sulfide
C) carbon disulfide
D) carbon sulfur
E) carbon disulfur

Question 27

Carbon tetrafluoride is a refrigerant and potent greenhouse gas. Which of the following is the molecular formula for this compound?

A) CF
B) C(IV)F
C) C₄F₄
D) C₄F
E) CF₄

Question 28

What is the name of CaCO₃, a common calcium supplement and antacid?

A) calcium carbon trioxide
B) calcium bicarbonate
C) calcium carbonate
D) calcium cyanide
E) calcium chlorite

Question 29

Iron(II) is an example of a(n) ________.

A) cation
B) anion
C) ionic bond
D) covalent bond
E) salt

Question 30

What is the ratio of ions in this lattice of lithium (the larger spheres) and oxygen (the smaller spheres) in Li₂O?

A) 1 Li:1 O
B) 2 Li:1 O
C) 2 O:1 Li
D) 4 O:5 Li
E) 4 Li:5 O

Question 31

What is the name of Na₂SO₃, a preservative in many foods and drinks?

A) sodium sulfite
B) sodium sulfate
C) disodium sulfur trioxide
D) sodium sulfur trioxide
E) disodium trisulfite

Question 32

What are the charges on the ions that make up this lattice of lithium (the larger spheres) and oxygen (the smaller spheres) in Li₂O?

A) Li has a -1 charge and O has a +1 charge.
B) Li has a +1 charge and O has a -1 charge.
C) Li has a -1 charge and O has a +2 charge.
D) Li has a +1 charge and O has a -2 charge.
E) Neither lithium nor oxygen is charged.

Question 33

Vinegar (C₂H₄O₂) and baking soda (NaHCO₃) are combined together and the resulting mixture bubbles, releasing a gas. This gas is a(n)

A) ionic compound because ionic compounds can be gases at room temperature.
B) ionic compound because baking soda contains sodium.
C) covalent compound because covalent compounds can be gases at room temperature.
D) covalent compound because baking soda contains sodium.
E) It is neither a molecule nor an ionic compound.

Question 34

In a covalent molecule,

A) nonmetals share electrons.
B) nonmetals donate electrons to metals.
C) metals donate electrons to nonmetals.
D) metals share electrons.
E) cations and anions are attracted to one another.

Question 35

In this covalent molecule of methane,

A) carbon is sharing its four electrons with the hydrogens.
B) carbon has donated four electrons to hydrogen, leaving it with a charge of +4.
C) hydrogen has eight electrons in its valence shell.
D) carbon is very unstable.
E) carbon does not have an octet of electrons.

Question 36

A compound contains magnesium and phosphate. What is the formula unit of this compound?

A) Mg₃P₂
B) MgPO₄
C) Mg₃(PO₄)₂
D) Mg₂(PO₄)₃
E) MgHPO₄

Question 37

Below is an illustration of an atom of fluorine. Which arrow points to the part of the atom involved in bonding?

A) A
B) B
C) C
D) Both B and C
E) None of the above are involved in bonding.

Question 38

Another name for an ionic compound is a(n) ________.

A) cation
B) anion
C) ionic bond
D) covalent bond
E) salt

Question 39

Which of the following is a diatomic molecule?

A) N₂
B) NaCl
C) H₂O
D) CO
E) Li₂O

Question 40

Below are four molecules and compounds. Choose the statement below that best describes these four.

A) All of these are ionic compounds.
B) I and II are covalent molecules, whereas III and IV are ionic.
C) II and III are ionic, whereas I and IV are covalent.
D) I, III, and IV and covalent, whereas II is ionic.
E) All of these are covalent molecules.

Question 41

Which of the structures are covalent molecules?

A) I and V
B) II, III, and IV
C) II and IV
D) V only
E) All of the choices are covalent molecules.

Question 42

Which of the following statements best describes the behavior of period 2 elements in a covalent molecule?

A) Period 2 elements lose electrons.
B) Period 2 elements gain electrons.
C) The nonmetals in period 2 form bonds so that they have a valence shell with eight electrons.
D) The nonmetals in period 2 form bonds so that they have a valence shell with two electrons.
E) Period 2 elements are not alike in any way.

Question 43

How many of chlorine's electrons are unpaired?

A) 0
B) 1
C) 2
D) 3
E) 4

Question 44

Which of these structures has two nonbonding pairs of electrons?

A) I and II
B) II only
C) III only
D) IV and V
E) III, IV, and V

Question 45

The total number of valence electrons in methane is

A) 2.
B) 4.
C) 8.
D) 16.
E) 40.

Question 46

The arrow is pointing to a(n)

A) triple bond.
B) double bond.
C) single bond.
D) electron.
E) valence shell.

Question 47

What is the total number of valence electrons in the chloroethylene molecule (C₂H₃Cl)?

A) 6
B) 18
C) 21
D) 32
E) 62

Question 48

What is the most likely connectivity of the atoms in chloroethylene (C₂H₃Cl)?

A)
B)
C)
D)
E)

Question 49

Which of these structures represent ionic compounds?

A) I and III
B) I and IV
C) IV and V
D) II and IV
E) I and V

Question 50

How many bonds is chlorine most likely to form?

A) 0
B) 1
C) 2
D) 3
E) 4

Question 51

Which of the following Lewis dot structures best represents the chlorine atom?

A)
B)
C)
D)
E)

Question 52

Which of the structures contains a double bond?

A) I
B) II
C) III
D) IV
E) V

Question 53

How many nonbonding electrons are in the chloroethylene molecule (C₂H₃Cl)?

A) None
B) 6
C) 8
D) 10
E) 18

Question 54

In which of the structures are six electrons being shared between two atoms?

A) I
B) II
C) III
D) IV
E) V

Question 55

Which of these structures is a diatomic molecule?

A) I
B) II
C) III
D) IV
E) V

Question 56

In general, how do elements in group 6A behave when they are a part of a covalent bond?

A) These elements form two bonds to other nonmetals.
B) These elements form one bond to another nonmetal.
C) These elements donate two electrons to a metal.
D) These elements accept two electrons from a metal.
E) These elements do not interact with other elements.

Question 57

Lewis electron dot structures represent the

A) number of unpaired electrons in an atom.
B) total number of electrons in the atom.
C) number of protons in the atom.
D) number of valence electrons.
E) number of nonbonding electrons.

Question 58

Which of the following is the best Lewis structure for a molecule with the formula HCN?

A)
B)
C)
D)
E)

Question 59

In general, how many bonds does a nonmetal in the second period 2 form?

A) the same number as the number of nonbonding electrons in the atom
B) the same number as the number of unpaired electrons in the atom
C) the same number as the total number of electrons in the atom
D) eight, in accordance with the octet rule
E) It is impossible to predict the number.

Question 60

Select the statement that best differentiates between bonding and nonbonding electrons.

A) There are always more bonding electrons than lone pairs in a molecule.
B) Nonbonding electrons are less chemically important than bonding electrons.
C) Nonbonding electrons do not count toward an atom's octet of electrons.
D) Bonding electrons are shared and nonbonding electrons are not shared.
E) The more nonbonding electrons that an atom has, the more unstable the atom.

Question 61

Which Lewis dot structure is the same molecule as 2-methylbutane, shown below in its ball-and-stick model?

A)
B)
C)
D)
E)

Question 62

Which statement best describes the difference between electron geometry and molecular shape?

A) There is no real difference between these terms.
B) Electron geometry is two dimensional, whereas molecule shapes are three dimensional.
C) Electron geometry is theoretical, whereas molecular shape is real.
D) Electron geometry refers to the arrangement of electrons around a central atom, whereas molecular shape refers to the arrangement of atoms.
E) Answers b, c, and d are all true.

Question 63

This is a _______ model of a molecule.

A) ball-and-stick
B) space-filling
C) Lewis
D) wire frame
E) tube

Question 64

When determining the shape of a molecule, it is necessary to count electron groups. Which of the following is NOT an electron group?

A) a single bond
B) a double bond
C) a triple bond
D) a core electron
E) a nonbonding pair of electrons.

Question 65

What is the purpose of Valence Shell Electron Pair Repulsion (VSEPR) theory?

A) To predict which atom is the central atom in a Lewis structure.
B) To identify the lone pair and valence electrons in a molecule.
C) To determine the shape of a molecule from the Lewis structure.
D) To determine the shape of a molecule from a molecular model.
E) To determine the arrangement of valence electrons in an atom.

Question 66

This table shows the relationship between the number of electron groups, the resulting electron geometries, and the corresponding angles between groups of electrons. Some of the blanks in the table have been filled in for you. The angle in the cell labeled A in the above table should be:

A) 360º
B) 180º
C) 120º
D) 109.5º
E) 90º

Question 67

Why are there many different ways to model and draw molecules?

A) There is no reason for this except to confuse students.
B) Each type of model and way of drawing communicates different characteristics of an actual molecule.
C) In different parts of the world, molecules are drawn differently.
D) As our understanding of the atom changed over time, we developed more accurate ways of drawing atoms and molecules.
E) Actually, there is currently only one correct way to draw or model a molecule.

Question 68

In this model of ethane, the dark grey balls represent _______ and the white balls represent _______.

A) nitrogen; hydrogen
B) oxygen; hydrogen
C) hydrogen; oxygen
D) carbon; hydrogen
E) hydrogen; carbon

Question 69

Which of the molecules below contain an atom with an expanded octet?

A) I and II
B) III only
C) IV only
D) I, II, and III
E) All of these molecules have an expanded octet.

Question 70

Why do electrons around a central atom arrange themselves as far apart from one another as possible, while still remaining attached to the central atom?

A) Actually, electrons don't do this, but atoms do.
B) The like charges of the electrons attract each other.
C) The protons direct the electrons to do this.
D) The like charges of the electrons repel each other.
E) There is no reason for this arrangement, it is just observed to be that way.

Question 71

Which of the following elements might have an expanded octet in a covalent molecule?

A) No elements have an expanded octet.
B) Atoms in period 2 might have an expanded octet.
C) Atoms in period 3 might have an expanded octet.
D) Any of the atoms in group two might have an expanded octet.
E) Any of the atoms in group three might have an expanded octet.

Question 72

What is the meaning of the "wedge bond" in the following structure?

A) This bond projects toward the viewer.
B) This bond projects away from the viewer.
C) This bond is in the plane of the paper.
D) These are nonbonding electrons.
E) It has no particular meaning.

Question 73

Which of the following is the best Lewis structure for a molecule with the formula C₂H₃Cl?

A)
B)
C)
D)
E)

Question 74

What feature of a molecule is illustrated by the ball-and-stick model of ethane on the left that is not illustrated by the Lewis dot structure on the right?

A) Nothing, these models illustrate the same thing.
B) the bonds
C) the types of atoms
D) the three-dimensional shape of the molecule
E) the core electrons

Question 75

The structure below is the Lewis structure of methane. The Lewis structure tells us many things about methane that are useful. However, it also suggests one characteristic of methane that is, in fact, false. What is this one characteristic?

A) The Lewis structure suggests that carbon has a full valence shell, but it really doesn't.
B) The Lewis structure suggests that carbon has four bonds, but it really doesn't.
C) The Lewis structure suggests that carbon is bonded to four hydrogens, but it really isn't.
D) The Lewis structure suggests that methane is flat, but it really isn't.
E) The Lewis structure suggests that methane is stable, but it really isn't.

Question 76

Which of the following statements best describes the meaning of an expanded octet?

A) "Expanded octets" are molecules in which an element expands its valence shell to gain an octet of electrons.
B) "Expanded octets" is a term that describes atoms that have more than eight electrons in their valence shells.
C) "Expanded octets" refers to atoms that, when bonded, must be larger than normal.
D) "Expanded octets" is used to describe elements that do not normally form an octet when bonded and would therefore have to expand to form the octet.
E) "Expanded octets" is used to describe how atoms accept electrons to attain a full valence shell.

Question 77

Which of the following wedge-dash drawings best represents the ball-and-stick model of methane as it is drawn below?

A)
B)
C)
D)
E)

Question 78

What does a ball-and-stick model show clearly that a space-filling model does not?

A) relative atom size
B) relative bond length
C) relative bond strength
D) bond angle
E) atom identity

Question 79

How many multiple bonds are in the chloroethylene molecule (C₂H₃Cl)?

A) None
B) 1 double bond
C) 1 triple bond
D) 2 double bonds
E) 1 double and 1 triple bond

Question 80

Which of the following models does NOT contain a carbon with tetrahedral geometry? Assume that all atoms in all structures are visible.

A)
B)
C)
D)
E)