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Honors Chemistry: Week of November 2

GPS

SC1 Students will analyze the nature of matter and its classifications.

d. Use IUPAC nomenclature for both chemical names and formulas:

SC2 Students will relate how the Law of Conservation of Matter is used to determine chemical composition in compounds and chemical reactions.

b. Experimentally determine indicators of a chemical reaction specifically precipitation, gas evolution, water production, and changes in energy to the system.

 

Monday: Nomenclature Review Assignment due: Page 118, #6, 8, 15, 18-21, 24-28, 42, 44-51

 

Tuesday: No School – Study for tomorrow’s test.

 

Wednesday: No homework.  Dress for lab tomorrow. (No prelab)

 

Thursday: Indicators of a Chemical Reaction Lab.  Complete lab report (informal).  Study for ion quiz.

 

Friday: Page 223, #1 and page 234, #9,10,12,15,16,18,19 and balance the equations

Honors Chemistry: Reactions Unit

Reactions (Chapters 7 & 8) Notes and Assignments

GPS: 

SC1 Students will analyze the nature of matter and its classifications.

d. Use IUPAC nomenclature for both chemical names and formulas:

SC2 Students will relate how the Law of Conservation of Matter is used to determine chemical composition in compounds and chemical reactions.

a. Identify and balance the following types of chemical equations:

Synthesis, Decomposition, Single Replacement, Double Replacement, Combustion

b. Experimentally determine indicators of a chemical reaction specifically precipitation, gas evolution, water production, and changes in energy to the system.

 

 

Essential Question:  How do we write about reactions?

 

reactant – starting substance in a chemical reactions

product – new substance formed in a chemical reaction

® (yields).symbol for the reaction itself.

 

Know  phase symbols: See page 221

precipitate (ppt) – a solid that separates from a solution

Use of up and down arrows for escaping gas and precipitate

(See back of your reference sheet)

 

Gases: H₂, N₂, O₂, F₂, Cl₂, Nobles, CO₂, NH₃

Liquids: Br₂, Hg, H₂0

Solids: All other elements

Compounds – see solubility rules.

 

Homework:  Page 223, #1 and page 234, #9,10,12,15,16,18,19

 

 Recall Law of Conservation of Matter/Mass.  Chemical equations must adhere to the law.

Sample 7.3, Sample and Practice 7.4 (page 230+)   

 

Homework: Balance same equations as above.

 

 

“Indicators of a Chemical Reaction” lab. 

 

 

Essential Question:  How do you classify reactions?

 

1. Synthesis:  2 or more substances combine to form a new compound

    (A + X ®  AX) Ex: 2 Mg + O₂ ® MgO

2. Decomposition: a single compound breaks into 2 or more simpler substances.    

(AX ® A + X) Ex: 2 H₂O ® 2 H₂ + O₂

3. Single Replacement: one element replaces a similar element in a compound.

(A + BX ® AX + B    OR    Y + BX ® BY + X)

    Ex:  Zn + 2 HCl ® ZnCl₂ + H₂    (save H2 in a balloon)

4. Double Replacement: the ions of two compounds exchange places

    (AX + BY ® AY + BX) Ex:  2 KI + Pb(NO₃)₂ ® PbI₂ + 2 KNO₃

5. Combustion: a substance combines with oxygen releasing a large amount of energy in the form of light and heat.  (note: Mg example)

    Ex: 2 H₂ + O₂ ® 2 H₂O

    hydrocarbon - compound made only of hydrogen and carbon

    hydrocarbon + O₂ ® CO₂ + H₂O  (Ex:  CH₄ + 2 O₂ ® CO₂ + 2 H₂O)

6.  If H₂CO₃ or H₂SO₃ form, they decompose immediately into (H₂O & CO₂ or SO₂)

 

Homework: Worksheet and classify reactions: Page 274, #32, 33

 

 

Essential Question:  What is a net ionic equation?

Students will receive instructional handout.

Sample 8.3 on page 251 and Practice

Homework: Net ionic equations worksheet

 

 

Essential Question:  Can you predict the products of a reaction?

double replacement reactions. 

    Recall: ions in two compounds exchange places.

    Products:  Mix to match cation with new anion.  (Square dance analogy)

 

Synthesis from elements (Make the compound based on nomenclature rules)

 

Recall combustion:  Reactions with oxygen results in light and heat.  

    combustion of hydrocarbon: yields CO₂ + H₂O

Homework: Worksheet (predict products) – Bottom half of assignment sheet

 

 

Essential Question: Can you predict the products of a reaction?  Inquiry lab.(Group project)

 

 

Activity Series: (“King of the hill” analogy)  Elements will replace elements below them on the table.

Homework: Complete lab and worksheet

 

 

Reactions review assignment on the back of the assignment sheet

 

AP Chemistry: week of October 26

College Board Course Description

III. Reactions

C. Equilibrium

1. Concept of dynamic equilibrium, physical and chemical; Le Chatelier’s principle;

equilibrium constants

2. Quantitative treatment

a. Equilibrium constants for gaseous reactions: Kp, Kc

b. Equilibrium constants for reactions in solution

 (2) Solubility product constants and their application to precipitation and the

dissolution of slightly soluble compounds

(3) Common ion effect

Assignment: Read Chapter 15

Monday: Go over Gases Test and Thermo Test.

Tuesday: Page 660, #13 & 17

Wednesday & Thursday: Page 661, #37. 39, 41a, 43-49 odd, worksheet

Due Friday: Prelab (handout) Le Chatelier Lab

Prelab:  Complete the prelab handout.

Also:  On a separate sheet of paper, write a hypothesis for each test.

    Part One will require one hypothesis.

    Part Two will require two hypotheses.

    Part Three will require three hypotheses.

You will not be graded on the hypotheses.  I will read them and determine if they are valid hypotheses.  I will not be checking to see if your predictions are correct. 

If they are OK, I’ll return them to you.  If there’s a problem, you will be asked to change them immediately.  This request will take time during class when you should be doing the experiment – so be careful when you write them.

Due Wednesday, 11/4: Lab report is different.   

Keep: identifiers, title, date you did the lab

Purpose:  Write an overall purpose for the whole lab.

For EACH PART(1,2,3):

A. Procedure

For EACH TEST (1 test in part one, 2 tests in part two, 3 tests in part three):

B. Hypothesis

C. Data

D. Conclusion and Discussion of Theory:  State whether the data supported or refuted your hypothesis.  Explain the results.

No “Sources of Error” section.  No additional Questions.

Appendix: Original hypotheses and original data

AP Chemistry: Equilibrium Notes and Assignments

Equilibrium: reactants ® products and products ® reactants, simultaneously,

  same rate (dynamic equilibrium)

Most reactions are reversible as long as the product(s) do not escaped.  (gas, ppt)

 

Equilibrium constant for jA + kB « IC + mD  (Sample 15.1 on page 532)

  Kc = [C]^l [D]^m  

          [A]^j [B]^k  

   

    Kp = (P_C)^l (P_D)^m

   (P_A)^j (P_B)^k

 

Homework: Read Chapter 15. Pg 660, #13

 

Equilibrium constants are usually written without units – but they have them.  Don’t write units unless specifically asked for them.

 

K_reverse = 1/K

 

If equation is multiplied by some factor: njA + nkB « nIC + nmD, then K_new = Kⁿ

Relationship of Kc and Kp: Kp = = Kc(RT)^Dn

 

Sample and practice 15.2 on page 634

 

Homework: Pg 660, #17

 

Kc(overall) = (Kc₁)(Kc₂)   The product of each step Kc

 

So while we can calculate thermodynamic functions for a reaction in steps, we can also calculate the equilibrium constant.  (Don’t get rules mixed up)

 

Chart    K thermo

reverse    1/K   change sign

coefficient factor     raise to power    multiply

steps    multiply    add

 

Sample and Practice 15.5 (page 638)    Homework: Page 660, #23

 

Pure solids and liquids are not included in equilibrium constants

(Thermodynamic activity of 1)  That’s why Ksp didn’t have a demoninator!

See example 15.6 on page 640.  (So solids, liquids are not.  Gases and aqueous solutions are.)

 

Calculating K from know equilibrium concentrations or pressures

    Sample and Practice 15.8.  Make sure you can use your calculator efficiently.

 

How to solve for K when some initial and equilibrium information is provided.

    See steps on page 642

Other things to remember. 

IF some initial concentration is zero, the reactions will produce some of that.

IF there is no zero concentration in the given information, a Q test is need to determine which direction the reaction will proceed.

    Q < K, the forward reaction will proceed (not enough products – numerator is small)

    Q = K, at equilibrium already

    Q > K, the reverse reaction will proceed (too much product – numerator is big)

 

Sample and Practice 15.9 on page 643.  Homework: Page 661, #31 & 33

 

Sample and Practice 15.10 on page 645.  Homework: Page 661, #37

 

Sample and Practice 15.11 on page 646.  Homework: Page 661, #39 & 41a

 

Sample and Practice 15.12 on page 646.  Homework: page 661, #43-49 odd

 

Homework:  Worksheet and Prelab (handout)

 

 

Le Chatelier's Principle (Section 15.7 on page 648)

1. Change in reactant or product concentration 

(Solids and liquids don’t matter as long as you have some.)

Add a component, reaction will use it.  Take a component, reaction will make it.

 

2. Reactions with gases:  Increase pressure (add an inert gas or reduced volume) favors fewer gases, if nothing is added or removed from system. 

 

3. van't Hoff law:  An increase in temperature favors the endothermic reaction.

To predict effect of temperature change you need to know which reaction (forward or reverse) is endothermic.  Add DH to reaction and treat it like a reactant or product. 

 

4. Effect of catalyst:  none on the equilibrium, just get there faster.

 

Note:  Only a change in temperature will change K.  See note on bottom of 652.

 

Samples 15.13 on page 653 and Integrative exercise on page 655

 

Homework: Pg 662, #51, 53, 55 and complete lab report.

 

 

 

Back to thermodynamics.

1. See section 19.7 (page 826).  Can calculate thermodynamic state functions at non-standard states.

    DG = DGo + RT ln(Q)    R = 8.3145 J/K mol, T in Kelvin

 

At standard condition:  Read paragraph right above Sample 19.10

 

Sample and Practice 19.11 on page 828

 

2. See Section 16.8 (p 819) "The equilibrium point occurs at the lowest value of free energy available to the reaction system."  DG = 0    So: DGo = -RT ln(K)

 

Solving for K = e^-(DG/RT)

 

DG    K

DG^o = 0    K = 1

DG^o < 0    K > 1

DG^o > 0    K < 1

 

Sample and Practice 19.12 on page 829

 

Homework: Pg 838, #73, 75, 77, 79, 106bcd

 

 

Assignment: AP Problem Set

 

 

Equilibrium Review List

1. Raoult’s Law:  P = C P^o

Partial pressure of component = mole fraction in liquid solution x pure vapor pressure

 

2. Dalton’s Law:  P_T = P₁ + P₂ + P₃ …..   Total pressure = sum of partial pressures

C_vapor = P/P_T Mole fraction in vapor = partial pressure / total pressure

 

3. How to write equilibrium expressions for Kc and Kp

4.   Kp = Kc (RT)^Dn   where Dn = (l+m) – (j+k)

 

5. for solutions:   A_aB_b(s) « a A⁺ + bB^-:  Ksp = [A]^a[B]^b

 

6. LeChatelier’s principle: concentration, temperature, pressure, catalyst

 

7. Relationship of thermodynamic state function and equilibrium constant

DG_f^o, DH _f^o. DS_f^o data  (free elements: DG_f^o and DH _f^o = 0)

DG = DH - TDS

DG = DG^o + RT ln Q

 

at equilibrium: DG = 0 = DG^o + RT ln K

DG^o = -RT ln K

 

K = e^{-(DGo / RT)}

 

 

Review Worksheet Answers

1C

2D

3B

4D

 

5b) i) 0.595M   ii) 0.0205M

5c) 0.251

5d) 1.18 atm

5e) 2.00

 

7a) 0.800 atm

7b) SO₂ = Cl₂ = 0.63 atm; SO₂Cl₂ = 0.17 atm

7c) 2.3 atm

 

8a) 5.4 x 10^-6 g AgBr

8b) 0.22 g AgBr

 

9a) 3.14 kJ/mol

9b) DH = 3.08 x 10⁴ J/mol, DS = 92.8J k^-1 mol^-1

9c) 332 K

9d) 0.281 atm

Honors Chemistry: week of October 26

GPS:

SC1 Students will analyze the nature of matter and its classifications.

d. Use IUPAC nomenclature for both chemical names and formulas:

SC3 Students will use the modern atomic theory to explain the characteristics of atoms.

e. Compare and contrast types of chemical bonds (i.e. ionic, covalent).

Advanced topic not covered by GPS

Objective: Students will predict molecular geometry from electron pairs of Lewis structures.

(Valence Shell Electron Pair Repulsion - VSPER)

Monday: Complete review assignment

Tuesday: Study for covalent bonding test

Wednesday:-Friday: Work on nomenclature review.

Friday: Ion Quiz #2

 

Honors Chemistry: Week of October 19

GPS

SC1 Students will analyze the nature of matter and its classifications.

d. Use IUPAC nomenclature for both chemical names and formulas:

SC3 Students will use the modern atomic theory to explain the characteristics of atoms.

e. Compare and contrast types of chemical bonds (i.e. ionic, covalent).

 

Advanced topic not covered by GPS

Objective: Students will predict molecular geometry from electron pairs of Lewis structures.

(Valence Shell Electron Pair Repulsion - VSPER)

 

 

Monday: Page 118, #10 & 11

 

Tuesday: Draw Lewis structures for SO₃, CO, N₂O, NI₃, PCl₃, CN^-, PO₄^3-  and draw dots for Molecular Model lab

 

Wednesday and Thursday: Molecular Models Lab

 

Friday:  ION QUIZ Today

Acid Nomenclature worksheet and bring boiling point lab report to class on Monday.

 

Portfolio due dates:

Research Diary Check: Monday, October 26

Complete Abstract Project: Thursday, November 19

Honors Chemistry: Covalent Bonding Unit (notes and asssignments)

Essential Question:  How do you communicate about compounds?

 

chemical bond.  (Forces that hold atoms together.)  See page 400.

covalent bonding: electron sharing (two non-metals)  Page 401

polar bond (uneven sharing) and non-polar bond (even sharing)  Page 402 

Using electronegativity to predict polarity.

molecule – neutral collection of two or more atoms covalent bound together.

    So: molecular compound - composed of molecules (covalent bonding)

molecular formula - the actual numbers and types of atoms in a molecule

 

 

diatomic molecule - molecule containing two atoms.

    Elements which are never found as single atoms, always diatomic 

H₂, N₂, O₂, F₂, Cl₂, Br₂, I₂

 

Recall binary compound (compound made of two and only two elements)  Review bond type from position on periodic table.

 

Naming binary covalent compounds from formula.  See prefixes Table 4.3 on page 104.

    Rules on page 104

 

Write formula from name:  Covalent - write element symbols in order listed, include the number of atoms that match the prefixes.  Remember no prefix on the first word = 1 atom.

 

NH₃ (ammonia) and H₂O (water)

 

Homework: Page 118, #10 & 11

 

There is more than one way to share electrons.

single bond – share one pair of electrons

double bond – share two pair of electrons

triple bond – share three pair of electrons

 

Drawing Lewis Dot for covalent compounds.

    Step 1: Calculate the number of electrons needed to fill all the atoms' valence shells.

    Step 2: Count valence electrons

    Step 3: Subtract to find number of shared electrons.

Step 4: If more than 2 atoms, select central atom.  (Usually C or atom with lowest electronegativity.)

    Step 5: Arrange shared electrons around central atom.

    Step 6: Draw in other atoms and unshared electrons.

    Step 7: Check (count for total valence electrons and check each atoms individual structure.)

 

Lewis structures for ions:  positive (subtract electrons from available count)

        negative (add electrons to available count)

        Examples: SO₃^2- and NH₄⁺

 

Homework: Draw Lewis structures for SO₃, CO, N₂O, NI3, PCl₃, CN^-, PO₄^3- 

 

 

Essential Question:  How do you predict the shape of a molecule?

 

Hybrid orbitals:  sp, sp², sp³ (Transparencies)

 

VSEPR - valence shell electron pair repulsion - structure is determined by minimizing electron pair repulsion.

    Note: if only two atoms - molecule is linear (2 points = line)

 

Zones of electron density: electron-domain: Consider electron geometry.

 

Molecular geometry - only see where atoms are bonded - not unbonded/lone pairs

Multiple bonds - act as a single zone of electrons

 

Names of shapes - transparency

 

Resonance - any structure can be used to predict geometry – See nitrate on page 433.

 

Note: lone pairs - require more space than bonded electrons    (shared pairs confined by two nuclei)

    multiple bonds require more space than single bonds (more electrons to repulse others)

 

Polarity: Can have canceling dipoles = nonpolar (See shapes transparency again)

 

Homework: Lewis Dots for Molecular Models Lab

 

Molecular Models lab (Not required to dress for lab)

 

 

Essential Question:  How do you communicate about covalent compounds?

Acid Nomenclature:  Handout

 

Homework: Acid nomenclature worksheet and bring boiling point lab report to class tomorrow

 

 

Essential Question:  What holds one molecule to another?

 

Page 489

Intermolecular forces - weak forces that cause atoms and molecules to be attracted to one another;  Van de Waals forces

intramolecular forces – within molecule - bonds

 

dipole-dipole:  attraction of positive dipole of one molecule to negative dipole of another molecule.  See Figure at bottom on page 489 and top of page 490

    Remember: Polar bonds does not necessarily mean a polar molecule:  CCl₄

 

hydrogen bond: very strong dipole-dipole.  attraction of positive H-end of a polar molecule for the unshared electron pair of a small, highly electronegative atom (F,N,O) at the negative end of another polar molecule (pg 490)  See Figure

 

London dispersion: temporary, instantaneous dipole due to uneven distribution of electrons.

Figures on page 491 11.5 on page 397

    bigger atoms/molecules = stronger due to more electrons that can be distributed unevenly

Take a look at Boiling Point lab

 

ion-dipole: between an ion and the partial charge of a polar molecule

    See Figure 15.1 on page 521

 

Homework: Complete Review Assignment

 

AP Chemistry: Week of October 19

College Board Course Description

E. Thermodynamics

1. State functions

2. First law: change in enthalpy; heat of formation; heat of reaction; Hess’s law; heats of vaporization and fusion; calorimetry

3. Second law: entropy; free energy of formation; free energy of reaction; dependence of change in free energy on enthalpy and entropy changes

Monday: 1^st & 2^nd period: Page 838, #61, 63, 65 & small handout
All periods: AP problems worksheet

Tuesday -Thursday: Review

Friday: Test thermodynamics

AP Chemistry: Change due date of Lab 6

New due date: Monday, 10/19

AP Chemistry: Week of October 12

College Board Course Description

E. Thermodynamics

1. State functions

2. First law: change in enthalpy; heat of formation; heat of reaction; Hess’s law; heats of vaporization and fusion; calorimetry

3. Second law: entropy; free energy of formation; free energy of reaction; dependence of change in free energy on enthalpy and entropy changes

Monday: Prelab 6 due tomorrow. To finish in one period – you will have to know what you are doing. 

2^nd period: Page 205, #61, 63, 67

All: page 206, #71, 73, 77

Tuesday: Lab 6 report due Friday, 10/16.

For lab report:

1. To find the mass of the water, you will have to look up the density of water at the temperature of your experiment. (Be sure to include a complete citation.)

2. You do not have NH₄Cl(aq) in your appendix.  But you do have NH₄⁺(aq) and Cl^-(aq). 

Wednesday: PSAT

Thursday: Page 474, #33, 35, 39a.  Read 11.6

Friday: Page 836, #39, 41, 43, 49, 51, 53, 55