Chapter 5

Question 1

True or false:

Free atoms occur rarely in nature

Answer 1

True

Question 2

True or false:

Most substances are compounds

Answer 2

Treu

Question 3

What is law of constant proportions?

Answer 3

All sample of a given compound have the same proportions of their constituent elements. For example water always has two hydrogen atoms for each oxygen.

Question 4

If compound A has 12.0 grams of carbon and 32.0 grams of oxygen and compund B has 36.0 grams of carbon and 96.0 grams of oxygen, are the two compounds the same?

Answer 4

Yes, because 12:32 = 36:96

Question 5

For Al₂O₃, what are the constituents?

Answer 5

2 aluminum and 3 oxygen

Question 6

True or false:

In a compound, the metal is listed last.

Answer 6

False. Metal first. For example Al₂O₃ aluminum is first

Question 7

True or false:

Element in compounds that are in higher rows are listed first. For example O₃S

Answer 7

False. Elements in lower rows should be listed first. Should be SO₃

Question 8

True or false:

Compounds which have elements which are to the left are listed first. For example CCl₄

Answer 8

True. Carbon is left of chlorine.

Question 9

Determine the number of each type of atom in Al₂(SO₄)₃.

Answer 9

Two Al, 3 S, and 12 O.

Question 10

True or false:

Molecular formula is the simpliest whole number ratio of elements.

Answer 10

False. Empirical formula is low whole number ratio. Molecular formula is actual number ratio.

Question 11

What is structural formula?

Answer 11

letters and bonds

Question 12

What is ball and stick model?

Answer 12

Balls for elements and stick for bonds.

Question 13

What is space filling model?

Answer 13

Balls next to each other no bonds showing.

Question 14

What are atomic elements?

Answer 14

Single atoms as their basic unit. Typically noble gases.

Question 15

What are molecular elements?

Answer 15

Typically two atoms of the same element bonded together. For example O₂. Also known as diatomic molecules.

Question 16

Write ionic formula for Al³⁺ and O^2-

Answer 16

Al₂O₃

Question 17

Write ionic formula for Ca²⁺ and NO₃^-

Answer 17

Ca(NO₃)₂

Question 18

True or false:

An ionic compound is typically a metal together with one or more nonmetals.

Answer 18

True

Question 19

True or false:

In an ioic compound the charge of the cations must cancel the charge of the anions.

Answer 19

True. For example Mg²⁺ cancels O^2- in MgO

Question 20

What is a Type I ionic compound?

Answer 20

The metal has an invariant (fixed) charge.

Question 21

What is a Type II ionic coumpound?

Answer 21

The metal may contain different charges in different compounds. For example Fe²⁺ or Fe³⁺ These are usually transitional metals.

Question 22

What are binary compounds?

Answer 22

Contain only two elements.

Question 23

What are binary ionic compounds?

Answer 23

Metals with only one type of anion. For example, NaCl or CaBr₂

Question 24

Naming convention for binary (Type I) ionic compounds.

Answer 24

Name of cation (metal) + base name of anion (nonmetal) + ide. For example sodium chloride.

Question 25

What are the anions or fluorine, Chlorine, bromine, iodine, oxygen, sulfur and nitrogen?

Answer 25

fluoride, chloride, bromide, iodide, oxide, sulfide, nitride

Question 26

Naming convention for binary (Type II) ionic compounds.

Answer 26

Name of cation (metal) + (charge of cation in Roman numerals) + base name of anion (nonmetal) + ide For example, copper(II) sufide, CuS₂

Question 27

What are the following polyatomic ions: NO₂^-, NO₃^-, OH^-, ClO^-, ClO₂^-, ClO₃^-, ClO₄^-

Answer 27

nitrite, nitrate, hydroxide, hypochlorite, chlorite, chlorate, perchlorate

Question 28

Naming convention of molecular compounds

Answer 28

Prefix + name of first element + prefix + base name of second element + ide For example, P₂O₅ is diphosphorus pentoxide

Question 29

Naming convention binary acids.

Answer 29

hydro + base name of nonmetal + ic acid For example hydrochloric acid

Question 30

Naming convention of oxyacids

Answer 30

1. -ite oxyacids: base name of oxyanion + ous + acid For example sulfurous acid
2. -ate oxyacids: base name of oxyanion + ic + acid For example phosphoric acid

Question 31

Name test: CO

Answer 31

molecular: carbon monoxide

Question 32

Name test: CaF₂

Answer 32

ionic: calcium fluoride

Question 33

Name test: HF(aq)

Answer 33

acid, binary: hydrofluoric acid

Question 34

Name test: Fe(NO₃)₃

Answer 34

ionic: iron(III) nitrate

Question 35

Name test: HClO₄(aq)

Answer 35

acid, oxyacid, -ate: perchloric acid

Question 36

Name test: H₂SO₃(aq)

Answer 36

acid, oxyacid, -ite: sulfurous acid

Question 37

What is the formula mass?

Answer 37

formula mass = (# atoms of first element in formula x atomic mass of first element) + (# atoms of second element in formula x atomic mass of second element) + …

Question 38

What is formula mass of CCl₄ if C is 12.01 amu and Cl is 35.45 amu.

Answer 38

1 x 12.01 amu + 4 x 35.45 amu = 153.8 amu

Question 39

C₂H₃O₂^-

Answer 39

acetate

Question 40

CO₃^2-

Answer 40

carbonate

Question 41

HCO₃^-

Answer 41

hydrogen carbonate

Question 42

OH^-

Answer 42

hydroxide

Question 43

NO₃^-

Answer 43

nitrate

Question 44

NO₂^-

Answer 44

nitrite

Question 45

CrO₄^2-

Answer 45

chromate

Question 46

Cr₂O₇^2-

Answer 46

dichromate

Question 47

PO₄^3-

Answer 47

phosphate

Question 48

HPO₄^2-

Answer 48

hydrogen phosphate

Question 49

NH₄⁺

Answer 49

ammonium

Question 50

ClO^-

Answer 50

hypochloride

Question 51

ClO₂^-

Answer 51

chloride

Question 52

ClO₃^-

Answer 52

chlorate

Question 53

ClO₄^-

Answer 53

perchlorate

Question 54

MnO₄^-

Answer 54

permanganate

Question 55

SO₄^2-

Answer 55

sulfate

Question 56

SO₃^2-

Answer 56

sulfite

Question 57

HSO₃^-

Answer 57

hydrogen sulfite

Question 58

HSO₄^-

Answer 58

hydrogen sulfate

Question 59

O₂^2-

Answer 59

peroxide

Question 60

CN^-

Answer 60

cyanide

Question 61

F^-

Answer 61

anion: fluoride

Question 62

Cl^-

Answer 62

anion: chloride

Question 63

Br^-

Answer 63

anion: bromide

Question 64

O^2-

Answer 64

anion: oxide

Question 65

I^-

Answer 65

anion: iodide

Question 66

S^2-

Answer 66

anion: sulfide

Question 67

N^3-

Answer 67

anion: nitride

Question 68

If carbon tetrachloride has a masss ratio of 11.8:1 chlorine to carbon mass ratio and there is 35 grams of chlorine, the mass of carbon is.

Answer 68

35 grams / 11.8 ~ 3.0 grams

Question 69

Write chemical formula for compound which contains two chlorine for each oxygen atom.

Answer 69

Cl₂O

Question 70

How many oygen atoms are there in Fe₂(SO₄)₃?

Answer 70

12

Question 71

Which of the following are molecular elements

copper

iodione

krypton

potassium

Answer 71

Iodine, I₂

Question 72

Which of the following is an ionic compound

BrF₅

HNO₃

MgSO₄

NI₃

Answer 72

MgSO₄ because Mg⁺ and SO₄^-

Question 73

What is formula for compound that forms between Sr and Br?

Answer 73

SrBr₂ because Sr²⁺ and Br^-

Question 74

What is the formula for the compound that forms between sodium and chlorite ions?

Answer 74

NaClO₂ because Na⁺ and ClO₂^-

Question 75

What is Li₃N

Answer 75

lithium nitride

Question 76

What is CrCl₃?

Answer 76

chromium (III) chloride

Question 77

What is BaSO₄?

Answer 77

barium sulfate

Question 78

What is PF₃?

Answer 78

phosphorus pentafluoride

Question 79

What is manganese (III) oxide?

Answer 79

Mn₂O₃ because O^2- and Mn³⁺

Question 80

What is H₃PO₄(aq)?

Answer 80

phosphoric acid

Question 81

What is formula for hydrobromic acid?

Answer 81

HBr