Chapter 09 Chemical Formulas powerpoint

Chapter 9:

Chapter 9:

Chemical Names

Chemical Names

and Formulas

and Formulas

Mayfair High

Mayfair High

Mr. Falk

Mr. Falk

Chemistry Standards

 2a – Students know atoms combine to

form molecules by sharing electrons to form covalent or metallic bonds or by

exchanging electrons to form ionic bonds

 2g – Students know how electronegativity

and ionization energy relate to bond formation

 5 – Acids, bases and salts are three

 Objective: Students will be able to

name and write formulas for

monatomic and polyatomic ions.

9.1 Naming ions

1+ 2+

3+

3- 2-

1-N o io n s Transition metals: variable charges

Monatomic ions of the

representative elements

1A

2A 3A 4A 5A 6A 7A

8A

Monatomic ions of the transition metals

 Transition metals form more than one ion.

We use a Roman numeral in the name to indicate the charge.

Examples:

 Cu2+ copper (II) ion

 Cu+ copper (I) ion

 Fe3+ iron (III) ion

Note these exceptions to the transition rule:

 Ag+ silver ion (always +1)

 Cd2+ cadmium ion (always +2) (no

Roman

 Zn2+ zinc ion (always +2)

 Even though they are not transition

metals, tin and lead behave like transition metals. They do get a Roman numeral.

 Sn2+ tin (II) ion

 Sn4+ tin (IV) ion

 Pb2+ lead (II) ion

Negative monatomic ions

 oxygen  oxide O

2- bromine  bromide Br

- You do:

nitrogen, iodine, sulfur, fluorine

 Answers:

-Example Qs:

Example Qs:

Give the formula and name for each ion.

1. Phosphorus atom gains 3 e

-2. Manganese atom loses 2 e

-P

manganese (II) ion

Polyatomic ions to memorize:

Quiz on Tues. on both monatomic

and polyatomic ions! Study!!

NH4+ ammonium

SO₄2- sulfate

SO₃2- sulfite

CO₃2- carbonate

C₂H₃O₂- acetate

NO₂- nitrite

NO₃- nitrate

OH- hydroxide

CN- cyanide PO

Name these ions…

1. O

2-2. Li+

3. Cr3+

4. Ag+

5. SO₄

2-6. NH₄+

7. CN

-oxide ion lithium ion

chromium (III) ion silver ion

sulfate ion

ammonium ion cyanide ion

Write formulas for:

8. copper (II) ion 9. nitrate ion

10. acetate ion 11. sulfide ion 12. lead (II) ion

Cu2+

NO₃

-C₂H₃O₂

S

End of lesson 9.1

9.2 Ionic compounds

9.2 Ionic compounds

names and formulas

Standard

 2a – Students know atoms combine by

Objective:



Students will name and write formulas

To write names of ionic compounds:

Name the positive ion…

Example: lithium bromide

Writing formulas



Write the formula for calcium chloride.

Ca



CaCl

would not be electrically neutral!



Need another

Cl

-

One Ca

and two Cl

-

=

CaCl

-Ca

Criss-cross and simplify method for calcium chloride:

1. Write the metal and nonmetal with their charges

Cl

Cl

Ca

2+

1-2. The charge of the cation becomes the subscript of the anion and vice versa

3. Remove the +/- sign and bring the ions together in the formula.

Quick review

: Give the formula unit

and name for the compounds of:

 1. calcium and bromine  2. barium and sulfur

Compounds of transition metals contain a

Roman numeral in the name.



CuO = copper (II) oxide.



Fe

2

O

= iron (III) oxide

 Use the charge you know on the anion to get

the charge you don’t know on the cation. How do you know?

O is 2- so Cu must be 2+.

Give the formula unit and name for the compound of:

1. lead (II) and sulfur.

Pb2+ + S2-  PbS lead (II) sulfide

2. lead (IV) and bromine. Pb4+ + Br -  PbBr

State the name, including Roman

numeral if needed.

 a. SnBr₄  b. MnS  c. Sr₃N₂

tin (IV) bromide

manganese (II) sulfide strontium nitride

Why no Roman

numeral on (c)??

Compounds containing

polyatomic ions

Give the formula unit for : 1. potassium hydroxide.

 K+ + OH-  KOH

2. calcium nitrate.

Name these compounds:

 1. LiCN

 2. Fe(OH)₃  3. (NH₄)₂CO₃  4. NiPO₄

lithium cyanide

iron (III) hydroxide

ammonium carbonate

nickel (III) phosphate

Write formulas for:

 5. sodium carbonate

 6. calcium acetate

 7. lead (II) hydroxide

 8. aluminum cyanide

 9. ammonium sulfide

 Na₂CO₃

 Ca(C₂H₃O₂)₂

 Pb(OH)₂

 Al(CN)₃

End of 9.2

 Let’s review the daily objective.

 See homework on board!

 There will be a quiz on today’s work on

…?

End of lesson

9.2 Practice:

 1. silver nitrate

 2. barium nitrite

 3. sodium phosphate

 4. tin (II) cyanide

 5. zinc carbonate

 6. MgO

 7. Ca(NO₂)₂

 8. LiC₂H₃O₂

 9. Ni₃(PO₄)₂

 10. Co(OH)₃

AgNO

Ba(NO

)

Na

PO

Sn(CN)

ZnCO

magnesium oxide

calcium nitrite

lithium acetate

End of lesson

9.3 Molecular

compounds

Objectives:

•Students will be able to name and write

Review of molecular compounds



made of

nonmetals

only



smallest piece is a molecule



held together by shared e

s, not by

oppositely charged ions



can’t use ionic charges to figure out how

many of each atom



Always determine whether a

compound is ionic or molecular

before you try to name it!



Ionic compounds

: we use charges to

determine the formula.



Molecular compounds

: Prefixes in the

Prefixes

To write the name, write two words:

prefix + name, prefix + name + ide

Prefixes

No “ao” or “oo.”

Ex: tetraoxide  tetroxide.

Write the name for N2O4

Name these:

 N₂O  NO₂  Cl₂O₇  BaCl₂  CBr₄  CO₂



dinitrogen monoxide



nitrogen dioxide



dichlorine heptoxide



barium chloride



carbon tetrabromide

End of lesson.

9.4 Acids and bases

Objectives:

•Students will be able to name and write

Acids

 contain H and give off H+ when dissolved

in water

 Book says they are ionic, but we

generally consider them covalent compounds.

 See p. 272 Table 9.6. Memorize the

names and formulas of these 6 common acids.

strong

Bases

 Ionic compounds that contain OH

- Examples: NaOH, Ca(OH)₂

Write formulas for these:



diphosphorus pentoxide

tetraiodine nonoxide



sulfur hexafluoride

nitrogen trioxide



phosphorus trifluoride

aluminum chloride



P

O



I

O



SF



NO



PF

Try naming these:

1. HCl (hint: see p. 272)

2. PH₃

3. Ca(OH)₂

4. NCl₃

5. (NH₄)₂SO₄

1. hydrochloric acid

2. phosphorus trihydride

3. calcium hydroxide

4. nitrogen trichloride

End of lesson.

Some Laws:



1. Law of Definite Proportions- in a

sample of a chemical compound, the

masses of the elements are always in

the same proportions.



H

O always has the same proportion



2. Law of Multiple Proportions-

Dalton stated that whenever two

elements form more than one

compound, the different masses of

one element that combine with the

same mass of the other element

are in the ratio of small whole

numbers.

Multiple Proportions

 Example: NO and N₂O

 They both have the same elements, but

the second one has twice as much

 Compounds A and B both contain H

and O only.

 A = 5.20 g H, 41.3 g O

 B = 9.86 g H, 156 g O

 What is the lowest whole number ratio

A = 5.20 g H, 41.3 g O B = 9.86 g H, 156 g O

 156 g O / 41.3 g O = 156 g O x 5.20 g H

9.86 g H 5.20 g H 9.86 g H 41.3 g O

= 1.99 or 2:1 B:A

9.6 Summary of Naming

and Formula Writing



OBJECTIVES:

Use the flowchart to write the name of a

Bases

 A base is an ionic compound that produces

hydroxide in solution.

 The cation gives the name of the base.  OH - hydroxide ion

 NaOH sodium hydroxide

 Ca(OH)₂ calcium hydroxide

Equal quantities of acid and base will produce a salt and water.

 NH

3 is also a base because it can pick up a H +

and become NH₄

 A second definition of a base, being able to remove

H from solution

 Ammonia will become ammonium ion.

 _NH

Section 9.5

Summary of Naming and

Formula Writing



OBJECTIVES:

Use the flowchart in Figure 9.20 to write

Helpful to remember...

1. In an ionic compound, the net ionic

charge is zero (criss-cross method)

2. An -ide ending generally indicates a

binary compound

3. An -ite or -ate ending means there is

a polyatomic ion that has oxygen

Helpful to remember...

5. A Roman numeral after the name of

a cation shows the ionic charge of

the cation

Summary of naming and

formula writing



For naming, follow the flowchart- Fig.

9.20, page 277



For writing formulas, follow the

 _NaBr

 Na₂CO₃

 FeCl₃

sodium bromide

sodium carbonate

iron(III) chloride

 _{potassium chloride}

 _{magnesium nitrate}

 _{copper(II) chloride} K+ Cl

Mg2+ NO 3

Cu2+ Cl

 KCl

 Mg(NO₃)₂

 CuCl₂

Common Ion Charges

1+

2+ 3+ NA 3- 2-

A. Energy of Bond Formation

 Lattice Energy

Energy released when one mole

B. Vocabulary

ION

Polyatomic Ion

Monatomic Ion

1 atom 2 or more atoms

NO

NO

3

3

-

-Na

B. Vocabulary

COMPOUND

2 elements more than 2

elements

NaNO

NaNO

3

3

NaCl

B. Vocabulary

CHEMICAL FORMULA

Molecular Formula Formula

Unit

IONIC COVALENT

CO

CO

2

2

NaCl

“electron sea” METALLIC Bond Formation Type of Structure Solubility in Water Electrical Conductivity Other Properties Melting Point

A. Types of Bonds

Physical State

e- are delocalized

among metal atoms

IONIC COVALENT Bond Formation Type of Structure Solubility in Water Electrical Conductivity Other Properties

e- are transferred from metal to nonmetal

high

yes (solution or liquid)

yes

e- are shared between

two nonmetals low no usually not Melting Point

crystal lattice true molecules

A. Types of Bonds

Physical

A. Definition

 Acids

_{Compounds that form H}+ in water.

Formulas usually begin with ‘H’.

 Examples:

HCl – hydrochloric acid HNO₃ – nitric acid

Names of Variable Ions

Use a roman number after the name of a metal that forms two or more ions

Transition metals and

the metals in groups 4A and 5A

1.

2. CuCl (Cu+ ) copper (I) chloride

3. SnF₄ (Sn4+) tin (IV) fluoride

4. PbCl₂ (Pb2+) lead (II) chloride

Learning Check

Complete the names of the following binary compounds with variable metal ions:

6.FeBr₂ iron (_____) bromide

7.Cu₂O copper (_____) oxide

8.SnCl₄ ___(_____ ) ______________

9.Fe₂O₃ ________________________

Learning Check

Name the following compounds:

11. CaO

a) calcium oxide b) calcium (I) oxide

c) calcium (II) oxide

12. SnCl₄

a) tin tetrachloride b) tin (II) chloride

c) tin (IV) chloride

13. Co₂O₃

a) cobalt oxide b) cobalt (III) oxide

Name Review

Name the following compounds:

1. CaO calcium oxide

2. SnCl₄ tin(IV) chloride

Learning Check

Write the correct formula for the compounds containing the following ions:

4. Na+, S

1) NaS 2) Na₂S 3) NaS₂

5. Al3+, Cl

1) AlCl₃ 2) AlCl 3) Al₃Cl

6. Mg2+, N

Ionic Compounds

Ionic compounds form crystal lattices resulting from electrostatic interactions which maximize the +/- attractions while minimizing the +/+ and -/- repulsions.

Section 9.5

Summary of Naming and

Formula Writing



OBJECTIVES:

Use the flowchart in Figure 9.20 to write

Naming Anions

Change the anion ending to – ide

Naming Anions

Change the element ending to – ide

Naming Anions

Change the element ending to – ide

Naming Anions

Change the element ending to – ide

Naming Anions

Change the element ending to – ide

Naming Anions

Change the element ending to – ide

Naming Anions

Change the element ending to – ide

Cl1- chloride

Name these



Cl

-

N

3-

Br