Key TermsKey TermsUse the spaces below to define the key terms in your own words. Use the spaces below to define the key terms in your own words. 3.13.1Key TermKey Term Textbook DefinitionTextbook Definition Picture / In my own wordsPicture / In my own words

Chemical Chemical CompoundCompound

Chemical Chemical FormulaFormula

3.23.2Key TermKey Term Textbook DefinitionTextbook Definition Picture / In my own wordsPicture / In my own words

IonIon

Ionic Ionic CompoundCompound

Polyatomic Polyatomic IonIon

3.33.3Key TermKey Term Textbook DefinitionTextbook Definition Picture / In my own wordsPicture / In my own words

Molecular Molecular CompoundCompound

CCHAPTERHAPTER 3 – C 3 – COMPOUNDSOMPOUNDS FORMFORM ACCORDINGACCORDING TOTO AA SETSET OFOF RULESRULES

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3.1 – N3.1 – NAMINGAMING C COMPOUNDSOMPOUNDS

What information can we get from the periodic table?

How do you know if something is an element?

Combining Elements to Make Compounds

Each compound has a chemical _____________ and a chemical __________________. This formula tells you what ______________ and how _________ of each type are found in the compound.

The element’s _________________ tells you which elements are present. The ___________________ tell you how many atoms of the element are present in one __________________ of that compound.

Examples: HCl – has 1 atom of hydrogen and 1 atom of chlorine Na2O – has 2 atoms of sodium and 1 atom of oxygen MgF2 – has 1 atom of magnesium and 2 atoms of fluorine Pb2O3 – has 2 atoms of lead and 3 atoms of oxygen

Practice:Compoun

d Elements present How many of each?NaClHCO3CuNO3FeOPbO2NOCBr4

Naming Chemical Compounds

In 1987 a French chemist created a naming system for chemicals. He decided to use the chemical name for each _________________ in the compound, always putting the _________________ first.

THIS IS STILL THE SYSTEM USED TODAY!!!

Homework Assignment – Check and Reflect Pg. 143

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1. What information can you determine from a chemical formula?

2. Identify the elements in each of the following compounds.

a. HF(g)

b. Li2O(s)

c. K3O(s)

d. Ni2O3(s)

e. HgCl2(s)

3. How many atoms are indicated in the formula of each of the following compounds?

a. Silver chloride – AgCl(s)

b. Calcium oxide – CaO(s)

c. Magnesium nitride – Mg3N2(s)

d. Aluminium oxide – Al2O3(s)

e. Scandium sulfide – Sc2S3(s)

4. Write the chemical formula for each of the following compounds:

a. Sodium sulfide, which has two atoms of sodium and one atom of sulfur

b. Aluminium fluoride, which has one atom of aluminium and 3 atoms of fluorine

c. Oxygen gas, which has two atoms of oxygen

d. Glucose, which has 6 carbon atoms, 12 hydrogen atoms, and 6 oxygen atoms

5. Acetylsalicylic acid, commonly called aspirin, has the chemical formula C9H8O4(s). Urea, also called carbamide, has the formula H2NCONH2(s). Compare and contrast the two formulas in terms of total elements and atoms.

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3.2 – I3.2 – IONICONIC C COMPOUNDSOMPOUNDS

A pure substance that is formed as a result of the __________________ between particles of opposite ____________________. These particles are called ________________. These particles have opposite charges:

One is ____________ (cation) The other is ____________ (anion)

The positively charged particle is a metal, the negatively charged particle is a non-metal.

Properties of Ionic Compounds:

Made from a ______________ and a ____________________ ______________ melting and boiling points Good electrical conductivity Distinct ___________________ shape (aka “crystal lattice

structure) _________________ at room temperature http://www.youtube.com/watch?v=buWrSgs_ZHk

Ions

When the compound is _________________________ in water, the metal and non-metal form an __________________ solution of _______________.

An ______________ is an atom of a group of atoms that have become electrically charged by _____________ or _______________ electrons. (Protons NEVER move!!!!)

When an ionic compound forms, metals give away _________________________, non-metals ______________ them.

Ion Charges

To indication ions in chemistry, we use a __________ sign or a ____________ sign to the upper right of the element ____________________ (ex: Na+, Cl-, PO43-).

Some ions can form when certain atoms of elements combine.

These ions are called _______________________ ions (poly- means “many”) Polyatomic ions are a group of __________________ acting as if they were one

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Practice:

Element

Ion Charge Ion Notation

Hydrogen

1+

Lithium 1+Nitrogen 3-Oxygen 2-Fluorine 1-Sodium 1+Magnesium

2+

Aluminium

3+

Sulfur 2-Iron 2+ or 3+Copper 1+ or 2+Lead 2+ or 4+

Polyatomic Ions

These atoms together act as a _________________ grouping in forming ________________ compounds. Common examples are listed in the table below.

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Naming Ionic Compounds – See “Cheat Sheets”

There are two rules to remember for naming ionic compounds:

1. The chemical name of the ______________ or positive ion (___________________) goes first, followed by the name of the non-metal or _______________________ ion (__________________).

2. The name of the _____________________ negative ion changes its ending to ____________.

There is one exception to these naming rules. Where negative ions are ________________________ ions, their name remains unchanged.

Find lead, iron and copper on your periodic table. What do you notice?

Some elements have ____________ than one possible ____________ listed beside them. This is common in ___________________ metals.

To show which ion is being used in a chemical name, we add a ______________ ________________. Ex: Iron (II) oxide is a compound containing the Fe2+ ion. Iron (III) oxide contains the Fe3+ ion.

Once you know the ion _____________ and the chemical name of a substance, you can find its chemical ________________. The following steps will help you write the formulas for ionic compounds. These steps are also listed on your “cheat sheets”.

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Practice:

Compound Metal Ion Non-metal Ion Formulasodium chloridecalcium oxideiron (II) fluoridemagnesium nitridecesium nitridelead (II) sulfidecobalt (II) phosphidezinc bromidetungsten (VI) iodide

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Step 3Write the formula by indicating how many atoms of each element are in it. Do not include the ion charge in the formula! Place the number of atoms of each element in a subscript after the element's symbol. Then simplify if necessary.

Step 2Balance the ion charges. The positve ion charge must cancel off the negative ion charge. We will do this by "swapping" and "dropping"

Step 1Print the element's symbol with its ion charge. Next to it, print the non-metal element's symbol with its ion charge.

potassium fluoridelithium selenideberyllium fluoridebarium hydroxideiron (III) fluoride

Ion charges occur in a patter in the periodic table. What is it?

All of the elements in a group share common ion charges:

All of the alkali metals form ions with a charge of ___________ All alkaline-earth metals form ions with a charge of ___________ All halogens form ions with a charge of __________ All elements in group 16 form ions with a charge of __________ The noble gases don’t form _____________

We can also write a name for any given chemical formula, using our periodic tables. This is based on the naming rules:

1. The chemical name of the metal or positive ion (cation) goes first, followed by the name of the non-metal or negative ion (anion).

2. The name of the non-metal negative ion changes its ending to –ide.

Examples:

LiBr - _____________________ __________________________

K2S - ______________________ ___________________________

Mn3N2 - ____________________ __________________________

Practice:

Formula Metal name Non-metal name Chemical name

NaCl

Na2O

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CaS

CaF2

PbO

PbO2

CsCl

BaCl2

Cr3N2

FeP

BeI2

WN2

V3P5

Re2O7

Homework Assignment – Check and Reflect Pg. 149

1. What is an ionic compound?

2. List three properties of all ionic compounds.

3. How is an ion formed?

4. What is the difference between Fe2+ and Fe3+?

5. If an element has more than one possible ionic charge, how is that piece of information represented in a chemical name?

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6. Outline the steps for writing the chemical formula of an ionic compound.

7. Write the formula for the following compounds:

a. sodium fluoride

b. magnesium sulfide

c. lithium oxide

d. iron (III) chloride

e. copper (II) phosphide

f. magnesium iodide

g. iron (II) phosphide

h. aluminium nitride

8. Write the chemical name for the following formulas:

a. LiCl(s)

b. Ca3P2(s)

c. AlBr3(s)

d. PbS2(s)

e. Fe2O3(s)

f. Na2O(s)

g. CaS(s)

h. CuSO4(s)

3.3 – M3.3 – MOLECULAROLECULAR C COMPOUNDSOMPOUNDS

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Molecular compounds are a combination of ____________________________. They are a pure substance with the following properties:

Can be _____________, liquids or _________________ at room temperature Insulators or poor ______________________ of electricity Relatively __________ melting and boiling points because of the weak

________________ between molecules

The _______________ for molecular compounds are similar to those of ionic compounds. However, because _______-__________ are combining there are no ____________________ present. Because of this, it is very hard to predict how non-metals will combine to form a compound.

Let’s take a look:

Well, the formula still tells you exactly which __________________ are in the compound and how _______________ of each type of __________________.

Naming Molecular Compounds

A lot of these compounds are known by their _______________ name. Ex: water, ammonia, sugar, rubbing alcohol.

All molecular compounds can be named using the following rules:

1. The first element in the compound uses the _________________ name EXACTLY like it appears on the periodic table (just like metals in ionic compounds!)

2. The ________________ element in the compound has the ending –ide (just like non-metals in ionic compounds)

3. A ______________ is used to tell you how ______________ of each atom are present in the molecule

EXCEPTION – If there is only one of the first element, we do NOT include a prefix!!!!!

When there is more than _______________ atom of an element present in the compound, a prefix needs to be ____________________ in the name. The prefixes tell you how many of each atom are present in the compound. Examples:

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Chemical Name Chemical Formula

Carbon dioxideCarbon monoxideDihydrogen monoxideNitrogen monoxideNitrogen trioxideDinitrogen monoxideTrinitrogen monoxide

The name of a molecular compound ends up looking like this:

Prefix + first element Prefix + second element

Formula

Name

CO2 carbon dioxideN2O dinitrogen monoxideN2O3 dinitrogen trioxideNF3 nitrogen trifluorideCCl4 carbon tetrachloridePF5 phosphorus

pentafluoride

Practice:

Formula Name

NO

CO2

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PF3

CBr4

NF3

N2O3

P5Cl10

H2OSeI2

diphosphorous trichloridecarbon tetrafluoridenitrogen diselenidetetraselenium heptabromidedicarbon hexaiodidephosphorous monoselenidetrinitrogen octasulfidesulfur diiodidesulfur monoxide

Homework Assignment – Check and Reflect Pg. 153

1. Define a molecular compound and give an example of one.

2. List three properties of molecular compounds.

3. Draw a simple model to show a molecule for each of the following:

a. chlorine gas (Cl2(g))

b. phosphorus trichloride (PCl3(g))

c. nitrogen monoxide (NO(g))

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d. iodine bromide (IBr(g))

5. Which of the following compounds are molecular?

a. H2O(l)

b. NaCl(s)

c. NH3(g)

d. F2(g)

e. CuCl2(s)

f. CCl4(l)

6. Write the chemical formula for the following molecular compounds:

a. dinitrogen monoxide

b. sulfur trioxide

c. carbon tetrachloride

d. phosphorus pentachloride

e. carbon disulfide

7. Fill in the following Venn diagram to compare and contrast the properties of a molecular compound with those of an ionic compound.

Section Review – Pg. 154

1. Explain the two rules to follow when naming an ionic compound.

2. For each substance below, name the elements and indicate the number of each kind of atom present in one molecule.

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Ionic Compound Molecular Compound

a. HgF(s)

b. O2(g)

c. Na2S(s)

d. B2O3(s)

e. FeCl3(s)

3. When an ionic compound forms, what must be the sum of the ionic charges?

4. What kind of elements form molecular compounds?

5. Identify how many atoms of each element are present in the following compounds:

a. Glucose: C6H12O6(s)

b. Ethanol: C2H5OH(l)

c. Hydrogen peroxide: H2O2(l)

d. Rust remover: H3PO4(aq)

e. Fatty acid: C17H35COOH(aq)

6. Which of the following compounds are ionic and which are molecular?

a. PbO(s)

b. Al2S3(s)

c. F2(g)

d. H2O(l)

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e. NH3(g)

7. What is the formula for the ionic compounds with the following combinations of elements?

a. potassium and bromine

b. barium and oxygen

c. aluminium and selenium

d. calcium and nitrogen

e. copper and phosphorus

8. Write the formula for the following molecular compounds:

a. carbon monoxide

b. carbon dioxide

c. nitrogen dioxide

d. dinitrogen monoxide

e. disulfur dichloride

10.Write the formula for the following ionic compounds:

a. magnesium bromide

b. sodium phosphide

c. lithium fluoride

d. nickel (II) chloride

e. lead (IV) nitride

f. copper (I) sulfide

g. silver oxide

h. nickel (III) oxide

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11.In terms of ion charges and chemical changes, what is the difference between CuF(s) and CuF2(s)?

13.Which of the following formulas is/are not written correctly? Correct them.

a. Li3O

b. CuO

c. Mg3O2

d. HgCl2

e. FeCl

15.An unknown ionic compound is formed with the formula Z2S3(s).

a. What is the common ion charge of element Z? Explain.

b. What would be the new chemical formula of the unknown compound if the S (sulfur) was replaced with fluorine?

c. What would be one property of these two compounds?

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