Mrs. Cook's Blog

Honors Chemistry: Week of March 29

GPS: SC6. Students will understand the effects motion of atoms and molecules in chemical and physical processes.

 

Monday:  Page 497, #7 and review (See link at top of blog for review assignment.)

 

Tuesday:  Study for tomorrow’s test.

 

Wednesday:  Heat prelab

 

Thursday:  Heat lab report (Prelab, data, calculations, analysis questions) and bring the item you chose for ice cream lab.

 

Friday:  Spring Break – no homework

AP Chemistry: Week of March 29

College Board Course Description

I I. Structure of Matter

A. Atomic theory and atomic structure

    1. Evidence for the atomic theory

    2. Atomic masses; determination by chemical and physical means

    3. Atomic number and mass number; isotopes

4. Electron energy levels: atomic spectra, quantum numbers, atomic orbitals

5. Periodic relationships including, for example, atomic radii, ionization energies, electron affinities, oxidation states

B. Chemical bonding

1. Binding forces: Types: ionic, covalent, metallic, hydrogen bonding, van der Waals (including London dispersion forces) and Relationships to states, tructure, and properties of matter (Polarity of bonds, electronegativities)

2. Molecular models: Lewis structures, Valence bond: hybridization of orbitals, resonance, sigma and pi bonds, Valence Shell Electron Pair Repulsion (VSEPR)

3. Geometry of molecules and ions, structural isomerism of simple organic molecules and coordination complexes; dipole moments of molecules; relation of properties to structure

 

 

Monday: In class: Review.  Homework: Study for tomorrow’s test

 

Tuesday:  Test atomic theory and bonding.  Homework: Study for reaction half-test.

 

 

College Board Course Description

III. Reactions

D. Kinetics

1. Concept of rate of reaction

2. Use of experimental data and graphical analysis to determine reactant

order,

rate constants, and reaction rate laws

3. Effect of temperature change on rates

4. Energy of activation; the role of catalysts

5. The relationship between the rate-determining step and a mechanism

 

Read Chapter 14.

 

Wednesday: Page 615, #1, 2, 23, 27, 29

 

Thursday: Page 615, #5, 41, 45 and #7,10, 51, 55a,     MUST read Section 14.6 (page 597)

 

Friday: Page 621, #65, 67, 69 and Exam Review packets: Mulitple choice & Lab

AP Chemistry: Kinetic (Chapter 14) Notes and Assignments

Chemical Kinetics is concerned with the rate of the reaction and the reaction mechanism.  Both are determined experimentally.  (They have nothing to do with reaction stoichiometry.)

 

Rate of reaction:  (page 575) change in concentration of a reactant or product per unit time  (Note: spontaneous does not equal fast) 

    See graph on page 577.  Instantaneous rate (slope of curve at any specific time/point)

    Average rate - D[A] / Dt

    Relative rates are determined by stoichiometry.  Sample 14.3

 

Rate law, rate constant.  Differentiated rate law: shows how the rate of reaction depends on concentration.  This is the kind of rate law scientists mean when they just say, “rate law.”

See page 581 (middle of page) for formula

two important points:

1. Products do not appear because rate law is determined under conditions where the reverse reaction doe not contribute to overall rate.

2.  Values of k, m, n are determined experimentally and CANNOT be determined from balanced reaction.

3. Value and units of rate constant (k) are determined from the rate equation once m and n are known.

 

Second type of rate law: integrated rate law – Show how concentration depend on time

 

If you know one, and you know calculus – you know the other.  So either is sufficient

Experimental convenience determines which kind of rate law to use.

 

Know the rate law is important mainly because it is used to infer the steps involved in the reaction.

 

Page 581.  Reactant order (exponent).  Overall reaction order = sum of reactant orders

 

Method of initial rates.  Page 584 – Sample 14.6 

    See sentence at end that begins “Because [B] is not part of the rate law,”

Note: Initial rate method yields differentiated rate law.

 

Homework:  Read Chapter 14.  Page 615, #1, 2, 23, 27, 29

 

 

 

Equations for integrated rates law are one your equation sheet.

See Thermochemistry/Kinetics.

 

Zero order:  rate = -k So: [A] -v- time graph yields a straight line. 

    -k = slope of line and y-intercept = initial concentration

 

First order equation on your sheet:  ln[A]_t – ln[A]₀ = -kt

 

    rearrange: ln[A]_t = -kt + ln[A]₀ SO: ln[A] -v- time graph yields a straight line

   

    -k = slope of line and y-intercept = ln (initial concentration)

 

Second order equation on your sheet:  1/[A]t – 1/[A]0 = kt

 

rearrange: 1/[A]_t = kt + 1/[A]₀ SO: 1/[A] -v- time graph yields a straight line

   

    k = slope of line and y-intercept = 1/ (initial concentration)

 

So you can look at a graph with a straight line for something -v- time and the “something” will tell you the order of the reactant.     See page 587-589

 

Homework:  Page 615, #5, 41, 45   

 

 

 

Collision theory (collide, orientation, energy to break bonds)  (See page 593)

 

See Figure 14.5 on page 594. Activated complex (transitional), activation energy (E_a)

 

   

Discuss change due to temperature increase (more particles have activation energy) 

Graph on page 594 (left)  (more collisions and more energetic collisions)

 

Sample 14.10 on page 595  (Also endothermic or exothermic if DE = DH)

 

 

Arrhenius equation (top and bottom of page 595)  See your equation sheet.

 

    So plot ln k -v- 1/T and the slope will be E_a/R R = 8.314 J/mol K

 

    See Sample 14.11 on page 596.   Can determine Ea and then k at any temperature

 

catalyst – speeds up reaction by providing an alternate activated complex with a lower activation energy.  See graph on 606.

 

Homework:  Page 615, #7,10, 51, 55a   

    MUST read Section 14.6 (page 597)

 

 

 

Rate mechanism: series of steps of reactions.  Defintions 598 (elementary, unimolecular, bimolecular, termolecular, intermediate)

 

See italics on bottom of page 598

 

See Sample 14.13 on page 600

 

Read paragraph bottom of 600 to top of 601: rate determining step = slowest

    “Rate determining step governs the rate law for the overall reaction”

 

Sample in text on page 601-602 and Sample 14.14

 

See Sample in text on page 603-604 and italics on page 604.  Sample 14.15

 

Homework: Page 621, #65, 67, 69

 

 

AP kinetics problem worksheet 

 

"The Acid Catalyzed Iodination of Acetone" lab. 

Honors Chemistry: Week of March 22

GPS: SC6. Students will understand the effects motion of atoms and molecules in chemical and physical processes.

 

Monday, 3/22:

Due Friday, 3/26:  Venn Diagram Worksheet and Page 497, #1-6

Due Monday, 3/29:  KMT worksheet

 

Tuesday, 3/23 – Thursday, 3/25:  Solids, Liquids, Gases lab (Dress for lab each day.)  Lab report due on Friday, 3/26

 

Friday, 3/26:  Page 333, #2, 3 (Show work), 5, 6  and KMT worksheet assigned on Monday, 3/22

 

See link at top of blog for review assignment due on Tuesday, 3/30

Test on Wednesday, 3/31

AP Chemistry: Message for 1st period

Any first period student who wants to take a reactions half-test may come to Room 1210 at 7:50 AM on Wednesday, March 24.

AP Chemistry: Weeks of March 15 and March 22

College Board Course Description

I I. Structure of Matter

A. Atomic theory and atomic structure

    1. Evidence for the atomic theory

    2. Atomic masses; determination by chemical and physical means

    3. Atomic number and mass number; isotopes

4. Electron energy levels: atomic spectra, quantum numbers, atomic orbitals

5. Periodic relationships including, for example, atomic radii, ionization energies, electron affinities, oxidation states

B. Chemical bonding

1. Binding forces: Types: ionic, covalent, metallic, hydrogen bonding, van der Waals (including London dispersion forces) and Relationships to states, tructure, and properties of matter (Polarity of bonds, electronegativities)

2. Molecular models: Lewis structures, Valence bond: hybridization of orbitals, resonance, sigma and pi bonds, Valence Shell Electron Pair Repulsion (VSEPR)

3. Geometry of molecules and ions, structural isomerism of simple organic molecules and coordination complexes; dipole moments of molecules; relation of properties to structure

 

 

Monday, 3/15: Page 335, #45, 49 (no formal charge), 51ac, 53, 55, 61

 

Tuesday, 3/16: Page 384  #17 – 35 odd, 47, 51a-d, 53  And Molecular Models Lab

 

Wednesday, 3/17:  Page 290, #25, 27, 31, 33a, 35, 37, 41, 45, 94 and page 334, #37

 

Thursday, 3/18: Pg 472, #15, 19, 23, 25, 29, 31, 43, 45, 71-77 odd

 

Friday, 3/19:  AP Worksheet: Atomic Theory and Bonding

 

GHSGT (3/22-3/25):  Students will be working on assigned problems and/or lab in 2^nd and 4^th periods (short classes).  First period will not meet.

 

Friday, 3/26: Molecular Models lab due.  AP Worksheet due.

 

Tuesday, 3/30:  Test atomic theory and bonding.

 

Honors Chemistry: Week of March 15

GPS: SC7. Students will characterize the properties that describe solutions and the nature of acids and bases.

b. Compare, contrast, and evaluate the nature of acids and bases:

• Arrhenius, Bronsted-Lowry Acid/Bases

• Strong vs. weak acids/bases in terms of percent dissociation

• Hydronium ion concentration

• pH

• Acid-Base neutralization

 

Monday, 3/15:  Page 589, #13-16 and “Conjugate Acid-Base Pairs” worksheet and review.

 

Tuesday, 3/16: Study for Acid-Base (Chapter 16 test)

 

Wednesday, 3/17:  Double check your project.  Be sure to bring rubric and parent form.  Book project at http://www.schoolrack.com/lhsread/files/

 

 

SCSh9. Students will enhance reading in all curriculum areas by:

a. Reading in All Curriculum Areas

• Read from a variety of subject disciplines and participate in discussions related to curricular learning in all areas

• Read informational texts in a variety of genres and modes of discourse

• Read technical texts related to various subject areas

b. Discussing books

• Discuss messages and themes from books in all subject areas.

• Respond to a variety of texts in multiple modes of discourse.

• Relate messages and themes from one subject area to messages and themes in another area.

• Evaluate the merit of texts.

• Examine author’s purpose in writing.

• Recognize the features of disciplinary texts.

c. Building vocabulary knowledge

• Demonstrate an understanding of contextual vocabulary in various subjects.

• Use content vocabulary in writing and speaking.

• Explore understanding of new words found in subject area texts.

d. Establishing context

 

Thursday, 3/18:  Book project due

 

SC6. Students will understand the effects motion of atoms and molecules in chemical and physical processes.

a. Compare and contrast atomic/molecular motion in solids, liquids, gases, and plasmas.

b. Collect data and calculate the amount of heat given off or taken in by chemical or physical processes.

c. Analyzing (both conceptually and quantitatively) flow of energy during change of state (phase).

 

Friday, 3/19: Start Kinetic Molecular Theory Unit (Notes and Assignments will be posted after test on 3/17.)  Video today.  Homework: Read Section 10.1 and define bold terms.  Page 325, #5-7.  Read introduction to Section 14.1

AP Chemistry: GHSGT

Practice test scores are posted on Pinnacle.

Review packets were given to all Juniors.

AP Chemistry: Bonding notes and assigments

Chemical bonds result from a more stable energy state.  See page 356 (Fig 9.15)

Basic definitions: 

ionic:  e- transfer results in ions that are electrostatically attracted to each other  (Lewis dot)

    covalent:  e- sharing (See page 305, Figure 8.5)

non-polar(even sharing), polar (uneven) 

See page 309, Figure 8.7 & dipole moments on page 310

    metallic:  sea of valence electrons

 

Use periodic table position to predict bond type (metal & nonmetal = ionic, 2 metals = metallic, 2 nonmetals = covalent

 

Use electronegativities on page 308 to predict bond type

Percent ionic character (Difference in electronegativities / larger electronegativity)

0%  -  5% (nonpolar)

5%  -  50% (polar)

> 50% (ionic)

    Sample 8.4 on page 309

 

Not all polar bonds result in polar molecules.  (Example: CO₂)

 

A closer look -

    Ionic = e- transfer to Noble gas or pseudo noble gas structure

    Crystal formation - see page 300 - So use empirical formula

    Ions will dissolve in water and become "free"

    Read about lattice energy (Sample 8.1)

 

Homework: Pg 333, #17, 19, 39

 

 

Localized Electron Bonding Model - see page 305

    lone pairs, bonding pairs

 

Lewis Dot Structures for Molecular Compounds  (File: WS DOT) (see Lewis Covalent.ppt)

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

Step 2: Count valence electrons (Add electrons for negative ions and subtract electrons for positive ions)

Step 3: Subtract to find number of shared electrons.

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

Step 5: Arrange other atoms around central atom.

Step 6: Draw in shared electrons.

Step 7: Draw in unshared electrons.

Step 8: Check: Count for total valence electrons and check each atoms individual structure.

 

Examples: NH₃, H₂S, CO₂, HCN, NBr₃, SO₃^2- and NH₄⁺

 

Homework:  Page 335, #45, 49 (no formal charge)

 

Bond length and bond strength:  More electrons being shared = shorter and stronger

 

Resonance:  Page 319.  Two or more Lewis structures:  Real = average.  Sample 8.10 (p 320)

   

Homework:  Page 335, #51ac, 53, 55

 

 

Exceptions to octet rule (page 322)

    a. Odd number of electrons (NO)  

b. Less than octet: BF3

Coordinate bonding - one atom donates both of the shared e-'s

    BF3 + NH3 ® nitrogen donates (w/boron)

    c. More electrons than octet (Period 3 and beyond - big enough to have d orbitals to use.)

        PCl₅ & ICl₄^-  (Sample 8.11)

 

Homework: Page 335, #61

 

 

Hybrid orbitals:      sp on pg 358     dsp³  on pg 361

    sp² on pg 359    d₂sp³ on pg 361

    sp³ on pg 359    review on pg 361

 

VSEPR - valence shell electron pair repulsion (starts on 344) - structure is determined by minimizing electron pair repulsion.

    See rules on page 346 and shape-names/pictures on page 347 and 350

 

    Note: lone pairs - require more space. (shared pairs confined by two nuclei)

Figure 9.7 on page 348      OR   all e-, no p+ ® more repulsion

Use H₂O (109.5^o), NH₃ (107^o), CH₄ (105^o) transparency

 

    Resonance - any structure can be used to predict geometry

    Multiple bonds - act as a single shared pair (Count zones of e-)

    See pictures & problems page 396-403

 

Homework: Pg 384  #17 – 35 odd, 47

 

Molecular orbitals – not tested in AP except for one small part.

Two kinds –

    Sigma – overlap of orbitals that extend towards each other, between the nuclei

    Figure 9.14 on page 356, Figure 9.17 on page 358

    Pi – orbitals lined up side by side and overlapping in two regions

    Figure 9.22 on page 362 through Figure 9.27 on page 364

 

Single bond = sigma

Double bond = sigma and pi

Triple bond = sigma and two pi

 

Note: resonance = delocalized pi bonding of unhybridized p-orbitals

    See pages 365 & 366

 

General Conclusions on page 368

 

Homework:  Page 386, #51a-d, 53

 

 

So far three kinds of bonding - ionic, metallic, covalent.  These are intramolecular forces.

Now look at intermolecular forces (van der Waals attractions).  Chapter 11, section 2

1. dipole-dipole attraction (positive end of one polar molecule is electrostatically attracted to the negative end of another polar molecule)  See picture page 439 and 440

2. hydrogen bonding - a special dipole-dipole attraction

    H to F,O,N.  About 5 - 10% strength of regular covalent bond. 

3. London dispersion forces:  (See picture on pg 441) "induce dipole"

    (-v- permanent dipole of polar molecules)

    Strength of forces increases with atom/molecule size

    larger molecules = more e-'s (farther from pull of own nucleus/electron shielding) = more London forces (I₂ > F₂)

 

The stronger the forces, the higher the melting points, boiling points, heat of vaporization, surface tension, viscosity, vapor pressure, etc.

Highest to lowest mp,bp,etc:  ionics, hydrogen bonding, dipole-dipole, London dispersion

    Note: LD is not the weakest.  It’s just that H-bond and dipole-dipole is in addition to the LD that’s in all types of matter (because they all have electrons)

   

Relation to state of matter -v- molecular size (In class: see chart with bp of different substances)

 

metals - "giant electron cloud" or "sea of valence electrons":  melting point, etc, raises with unpaired electrons through d's - highest in the middle of transition elements, then falls towards Zn column and rises through p orbital again (but not as high as mid‑d's)

 

Types of Solids:  See Table 11.7 on page 464

 

Homework: Pg 472, #15, 19, 23, 25, 29, 31, 43, 45, 71-77 odd

    and AP Worksheet - Atomic Theory and Worksheet - Bonding

 

AP Chemistry: Week of March 8

College Board Course Description

I I. Structure of Matter

A. Atomic theory and atomic structure

    1. Evidence for the atomic theory

    2. Atomic masses; determination by chemical and physical means

    3. Atomic number and mass number; isotopes

4. Electron energy levels: atomic spectra, quantum numbers, atomic orbitals

5. Periodic relationships including, for example, atomic radii, ionization energies, electron affinities, oxidation states

B. Chemical bonding

1. Binding forces: Types: ionic, covalent, metallic, hydrogen bonding, van der Waals (including London dispersion forces) and Relationships to states, tructure, and properties of matter (Polarity of bonds, electronegativities)

2. Molecular models: Lewis structures, Valence bond: hybridization of orbitals, resonance, sigma and pi bonds, Valence Shell Electron Pair Repulsion (VSEPR)

3. Geometry of molecules and ions, structural isomerism of simple organic molecules and coordination complexes; dipole moments of molecules; relation of properties to structure

 

 

Monday, 3/8:  Guided reading worksheet – Bohr model.  Page 248, #35a and 41ad

 

Tuesday, 3/9 and Wednesday, 3/10: Electron structure. Page 250, #63-73 odd

 

Thursday, 3/11:  Quantum numbers.  Page 250, #49, 51, 53 and worksheet (back of Monday’s guided reading)

 

Friday, 3/12: Page 333. #17, 19, 39, 45, 49