13 september 2011

13 September 2011

Objective: You will be able to: review chapter 2 concepts

Homework Quiz:1. Give the number of protons and

electrons in the ion Mg2+

2. Name the compound BaCl2

3. Write the formula for iodine heptachloride

Agenda

I. Homework QuizII. Ch. 1 #105III. Chapter 2 ReviewIV. Problems in Chapter 2?Homework: Chapter 1 Problem Set:

Thurs.

Announcement

Do I have your signed syllabus page yet?

You really want to be a TA for chemistry…

CHAPTER 2 REVIEW: ATOMS, MOLECULES, IONS

Atoms, Molecules and Ions

Review your notes from 2.1 – 2.5

Ionization A review of how to determine which

ion an atom makes

Valence Shell

Valence Shell: The most outer energy level.

1s22s22p63s23p3

1s 2s 2p 3s 3p

Stability

1s 2s 2p 3s 3p

1s 2s 2p 3s 3p

Valence Electrons: Label on your PTE1

2 3 4 5 6 78

Group 1

s ps p

New valence shell

Ions

Ion: An atom that has lost or gained one or more electrons

Cation: An atom that has lost an electron Positive Charge

Anion: An atom that has gained an electron Negative Charge

Octet Rule

Octet Rule: All atoms lose and gain electrons to form a full valence shell H, He = 2 All other elements = 8

Ions formed by group - Add to your PTE

12 3 4 5 6 7

81+

2+

3+ 3- 2- 1-

Cations Anions

Lose e- Gain e-

Set up a table:Element

# Valence E-

Loses or Gains E-?

Cation or Anion?

Charge of Ion

Symbol of Ion

Name of Ion

Set up a table:Element

# Valence E-

Loses or Gains E-?

Cation or Anion?

Charge of Ion

Symbol of Ion

Name of Ion

Number of Valence Electrons

1. Li2. Be3. B4. F5. O6. N7. Cl

8. P9. K10. Ca11. Al12. Se13. Br14. Kr

Anion or Cation?

Cation is positive because it has LOST electrons. It is a positive thing to have a cat,

and it would be sad if you lost your cat.

Anion is negative because it has GAINED electrons Mnemonic?

Symbols for Ions

Element SymbolCharge

Li+

Cl-

Al3+

Number, then + or – No need to write a “1” 1 is often invisible in chemistry

Names for Ions

Cations: Same name as the element Li+: lithium ion Sr2+: strontium ion

Naming Ions

Anions: Ending changes to “-ide” N3-: nitride ion O2-: oxide ion F-: fluoride ion S2-: sulfide ion Cl-: chloride ion Br-: bromide ion I-: iodide ion

Polyatomic Ions

NH4+ ammonium

CO32- carbonate

HCO3- hydrogen carbonate

ClO3- chlorate

CrO42- chromate

Cr2O72- dichromate

CN- cyanidePO4

3- phosphateHPO4

2- hydrogen phosphateH2PO4

- dihydrogen phosphate

More Polyatomic Ions

SO32- sulfite

SO42- sulfate

HSO4- hydrogen sulfate

OH- hydroxideNO3

- nitrateNO2

- nitriteMnO4

- permanganateO2

2- peroxide

14 September 2011

Objective: You will be able to: Name ionic and covalent

compounds Homework Quiz:

Write the formulas for:a. iron (III) chlorideb. ammonium sulfatec. dihydrogen monoxide

Agenda

Homework Quiz Questions about ch. 1 problem set? Chapter 2 reviewHomework: Ch. 1 problem set due

tomorrow

Formulas of Ionic Compounds

Formed by electrostatic attraction between cations and anions.

Examples:a. potassium bromideb. zinc iodidec. aluminum oxided. magnesium nitratee. iron (II) chloride(p. 54 for charges of transition metals)

Practice

1. rubidium sulfate

2. barium hydride

3. manganese (IV) oxide

4. ammonium carbonate

Names of Ionic Compounds

Examplesa. KBrb. CuClc. FeCl3

d. Cu(NO3)2

e. KH2PO4

f. NH4ClO3

Practice

1. MgBr2

2. Li2SO3

3. PbO

4. FeCO3

Molecular Compounds Prefix system

1 mono (**only used for secondelement in compound) 2 di 3 tri 4 tetra 5 penta 6 hexa 7 hepta 8 octa 9nona 10 deca

Naming Molecular Compounds

Examplesa. COb. CO2

c. N2O4

Practice Naming Molecular Compounds

1. SiCl4

2. P4O10

Writing Formulas for Molecular Compounds

Examplesa. nitrogen dioxide

b. dihydrogen monoxide

Practice Writing Formulas for Molecular Compounds

1. nitrogen trihydride (a.k.a. ammonia)

2. carbon tetrachloride (a.k.a. freon)

3. carbon disulfide

4. disilicon hexabromide

Naming Acids

Acid: any substance that yields hydrogen ions (H+) when dissolved in water

If the anion ends in “-ide”, the acid is a “hydro –ic” acid

HF hydrofluoric acidHCl hydrochloric acidHBr hydrobromic acidHI hydriodic acidHCN hydrocyanic acidH2S hydrosulfuric acid

Oxoacids

Contain hydrogen, oxygen and another element.

Used as reference acids to name other acids

H2CO3 carbonic acidHClO3 chloric acidHNO3nitric acidH3PO4 phosphoric acidH2SO4 sulfuric acid

More oxoacids

Often, two or more oxoacids have the name central atom but a different number of O atoms

1. Adding one O atom to an “-ic” acid = “per… -ic” acid

2. Removing one O atom from an “-ic” acid = “-ous” acid

3. Removing two O atoms from an “-ic” acid = “hypo…-ous” acid

Oxyacid examples

HClO3 chloric acid Add an oxygen: HClO4

perchloric acid Remove an oxygen: HClO2

chlorous acid Remove two oxygens: HClO

hypochlorous acid

Oxyacid Problems

Name the following oxyacids1. HNO2

2. H2SO3

3. H2CO4

4. H2SO2

Naming Bases

A base yields hydroxide (OH-) ions when dissolved in water

a. NaOH sodium hydroxideb. Ba(OH)2 barium hydroxide

(Some bases don’t contain OH-, but more on that later.)

Hydrates

Hydrates are compounds with a specific number of water molecules attached to them

Example: CuSO4·5H2O copper (II) sulfate pentahydrate

BaCl2·2H2O barium chloride dihydrate

15 Sept. 2011

Objective: You will be able to: Practice identifying subatomic

particles, isotopes, determining ionization, naming and writing formulas for compounds.

design a procedure to determine the formula of a hydrate.

Agenda

I. Questions about chapter 2 summer assignment?

II. Chapter 2 problem setIII. Design an procedure!Homework: Chapter 2 problem set:

Tues.Ch. 1-2 quiz Tues.

Your challenge!

Copper (II) sulfate hydrate Hydrate: a compound with water

“tagged on to” the crystal structure. Determine the number of molecules

of water of hydration per formula unit of copper (II) sulfate.

Your procedure…

1. A complete list of steps which include

1. specific quantities2. names of equipment you’ll need to

use3. some way to determine when your

procedure is “finished”2. Directions and equations for any

calculations you’ll need to makeDue: Monday!

Homework

Quiz on ch. 1-2 Tuesday Lab procedure: Monday

19 September 2011

Take out your lab notebook and turn to your procedure

Objective: You will be able to: carry our your procedure and

collect data to determine the number of molecules of water of hydration of copper (II) sulfate hydrate.

Agenda

I. Procedure discussionII. Carry out your procedureIII. Make calculationsHomework: Quiz on ch. 1-2

tomorrowChapter 2 problem set: Tues.Complete calculations (including

name of hydrate): Thurs.

Safety

Wear goggles until all your equipment has been cleaned and returned.

A hot crucible looks just like a cold crucible! Always use crucible tongs.

Work efficiently but carefully.

Technical notes

Heat the crucible uncovered or with the cover tilted to allow water vapor to escape.

Cool the crucible with the cover on. Cool the crucible in the desiccator

for very best results. Never mass a hot or warm crucible. Oil from your fingers will stick to the

crucible and effect your data.

Work Ethic

Work quickly. If you have “down time,” think: “What can I do now to save time later?”

Set up data tables and calculations while you wait.

This period

Carry out your procedure and collect data.

Begin calculations as soon as you can! Percent of water in the hydrate by

mass. Mole ratio of anhydrous CuSO4 to

H2O in your sample. Work to show how you got your

number of molecules of water of hydration.

Name of the hydrate

Homework

Quiz on ch. 1-2 tomorrow Chapter 2 problem set: Tues. Complete calculations (including

name of hydrate): Thurs.