Search found 60 matches
- Sat Mar 16, 2019 4:37 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: Final [ENDORSED]
- Replies: 9
- Views: 1103
Re: Final [ENDORSED]
Yes, it will be provided.
- Sat Mar 16, 2019 4:33 pm
- Forum: General Rate Laws
- Topic: H.W. Problem 15.17
- Replies: 5
- Views: 795
Re: H.W. Problem 15.17
Also why don't we calculate the order for reactant C?
- Sat Mar 16, 2019 4:29 pm
- Forum: General Rate Laws
- Topic: H.W. Problem 15.17
- Replies: 5
- Views: 795
H.W. Problem 15.17
Part A asks to calculate the order for each reactant.
The solution Manuel uses experiment 2 and 3 to solve for the order with respect to B. Why can't we use experiment 1 and 2?
The solution Manuel uses experiment 2 and 3 to solve for the order with respect to B. Why can't we use experiment 1 and 2?
- Sun Mar 10, 2019 6:25 am
- Forum: Student Social/Study Group
- Topic: Final
- Replies: 24
- Views: 2127
Re: Final
Information regarding review sessions have been posted on the website now.
- Fri Mar 08, 2019 8:39 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Midterm Review
- Replies: 3
- Views: 462
Re: Midterm Review
Yes, everything is posted on his website now.
- Fri Mar 08, 2019 8:37 pm
- Forum: Second Order Reactions
- Topic: Final
- Replies: 32
- Views: 2286
Re: Final
Did Dr.Lavelle mention how many questions the final might cover?
- Sun Mar 03, 2019 5:49 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Pt(s)
- Replies: 10
- Views: 1006
Re: Pt(s)
When there's no solid already in the rxn. Both the anode and cathode needs a solid.
- Sat Mar 02, 2019 11:48 pm
- Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
- Topic: Test #2
- Replies: 10
- Views: 1017
Re: Test #2
During your week 9 discussion
- Thu Feb 28, 2019 3:59 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Organization of cell diagrams
- Replies: 9
- Views: 800
Re: Organization of cell diagrams
Yes you need add Pt(s) when there's no solid.
- Sun Feb 24, 2019 3:23 am
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Concepts
- Replies: 2
- Views: 300
Re: Concepts
If delta G is negative: favors products and spontaneous in forward rxn.
If delta G is positive: favors reactants and non-spontaneous in forward rxn.
If delta G is positive: favors reactants and non-spontaneous in forward rxn.
- Sun Feb 24, 2019 3:16 am
- Forum: Balancing Redox Reactions
- Topic: Test 2 Material
- Replies: 13
- Views: 1303
Re: Test 2 Material
Yes balancing redox reactions will be on it.
- Sun Feb 24, 2019 3:15 am
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Spontaneity
- Replies: 6
- Views: 672
Re: Spontaneity
When delta G is negative the product is favored and spontaneous in forward rxn. When delta G is positive reactants are favored and non spontaneous in forward rxn and spontaneous in reverse rxn.
- Mon Feb 18, 2019 12:50 am
- Forum: Student Social/Study Group
- Topic: Midterms
- Replies: 5
- Views: 547
Re: Midterms
I believe so, but Dr. Lavelle will probably mention more details the day we get our midterms back.
- Sun Feb 17, 2019 4:29 am
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Gibbs Free Energy Signs
- Replies: 4
- Views: 434
Re: Gibbs Free Energy Signs
Negative = Spontaneous
Positive = Non-Spontaneous
Positive = Non-Spontaneous
- Sun Feb 17, 2019 4:27 am
- Forum: Calculating Standard Reaction Entropies (e.g. , Using Standard Molar Entropies)
- Topic: Midterm Grades
- Replies: 35
- Views: 2652
Re: Midterm Grades
The TA's also have the answer key for the midterm questions if you want to take a look at it before you get your midterm back.
- Mon Feb 11, 2019 1:55 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Units for enthalpy
- Replies: 6
- Views: 722
Re: Units for enthalpy
Either J or KJ. The final answer in J can be turned to KJ by simply dividing it by 1000.
- Mon Feb 11, 2019 1:48 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Hess's Law
- Replies: 5
- Views: 512
Re: Hess's Law
The test will provide the reaction similar to the homework problems.
- Sat Feb 09, 2019 3:48 pm
- Forum: Entropy Changes Due to Changes in Volume and Temperature
- Topic: Equations
- Replies: 1
- Views: 249
Re: Equations
Don't compare these two problems because 9.13 has an error. Check the errors in solution manual on the class website. :)
- Thu Jan 31, 2019 1:07 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Standard Enthalpy
- Replies: 4
- Views: 590
Re: Standard Enthalpy
O2 is 0 at standard state. All diatomic elements such as N2, O2, H2, will be zero and any single element from the periodic table.
- Thu Jan 31, 2019 12:59 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Bond Enthalpies
- Replies: 2
- Views: 375
Re: Bond Enthalpies
When we're solving for Enthalpy using standard enthalpy of formation method pure substances are zero.
- Wed Jan 30, 2019 5:43 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Best Method
- Replies: 7
- Views: 788
Re: Best Method
I think it really depends on what is given in the problem already.
- Sun Jan 27, 2019 12:35 am
- Forum: Phase Changes & Related Calculations
- Topic: Due date for Discussion Questions
- Replies: 8
- Views: 825
Re: Due date for Discussion Questions
Due Sunday at 11:59pm
- Sat Jan 26, 2019 6:08 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: Ka
- Replies: 6
- Views: 655
Re: Ka
The higher the Ka value the weaker the acid. Since H2SO4 doesn't have a ka value at all it is a strong acid.
- Fri Jan 25, 2019 12:15 am
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: Quiz #1 This friday
- Replies: 5
- Views: 657
Re: Quiz #1 This friday
Practice problems from homework, the audio-visual focus topic post-assessment, and UA workshop worksheets.
- Thu Jan 24, 2019 10:43 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Test 1
- Replies: 8
- Views: 743
Re: Test 1
My Plf recommended memorizing this list.
- Fri Jan 18, 2019 7:46 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: ignoring solids
- Replies: 6
- Views: 733
Re: ignoring solids
Solids and Liquids don't affect the reactant amount at equilibrium, so we leave them out.
- Fri Jan 18, 2019 7:32 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Test 1
- Replies: 6
- Views: 546
Re: Test 1
My TA said test 1 will be on Equilibrium and Acid & Base. Also, I doubt topics not discussed during the lecture will show up on the test.
- Fri Jan 18, 2019 7:29 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: Catalysts
- Replies: 7
- Views: 683
Re: Catalysts
Catalysts has no effect on the Equilibrium composition, but simply speeds up the process to Equilibrium.
- Sun Jan 13, 2019 9:55 pm
- Forum: Ideal Gases
- Topic: R [ENDORSED]
- Replies: 5
- Views: 536
Re: R [ENDORSED]
R = 0.0821 atm x L / mol x K
- Sun Jan 13, 2019 9:53 pm
- Forum: Student Social/Study Group
- Topic: New to Lavelle
- Replies: 32
- Views: 5203
Re: New to Lavelle
I take sessions with AAP for this class, doing homework and practice problems works best for me.
- Sat Jan 12, 2019 10:02 pm
- Forum: Ideal Gases
- Topic: bar or atm
- Replies: 8
- Views: 592
Re: bar or atm
I think Bar and atm are used interchangeably because the values are close.
- Tue Jun 12, 2018 12:47 am
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 3011158
Re: Post All Chemistry Jokes Here
Caution don't trip!
- Tue Jun 12, 2018 12:43 am
- Forum: General Science Questions
- Topic: Sig Figs
- Replies: 9
- Views: 1713
Re: Sig Figs
I round my final solution to keep my answer most accurate as possible.
- Tue Jun 12, 2018 12:41 am
- Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
- Topic: final [ENDORSED]
- Replies: 4
- Views: 840
Re: final [ENDORSED]
Yea I don't remember this being covered so probably not
- Sat Jun 02, 2018 4:23 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Bond Angles
- Replies: 7
- Views: 814
Re: Bond Angles
We don't need to remember the special cases just the main ones.
- Sat Jun 02, 2018 4:20 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Naming shape
- Replies: 7
- Views: 868
Re: Naming shape
Should look at its VSPER formula and that will take both the lone pairs and bonds into consideration to determine the shape.
- Tue May 29, 2018 2:59 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: VSEPR Drawing
- Replies: 7
- Views: 802
Re: VSEPR Drawing
We don’t need to draw the geometric shapes, but we should know how it looks and it’s lewis structure.
- Sun May 27, 2018 1:05 am
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 3011158
Re: Post All Chemistry Jokes Here
What do you call a clown who's in jail? A silicon.
- Sun May 27, 2018 1:03 am
- Forum: Resonance Structures
- Topic: ranking
- Replies: 11
- Views: 1475
Re: ranking
By formal charge starting from the lowest close to the zero.
- Sat May 26, 2018 1:19 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Why do lone pairs occupy the most space? [ENDORSED]
- Replies: 3
- Views: 4300
Re: Why do lone pairs occupy the most space? [ENDORSED]
The lone pair is more excited than bonding electron pairs.
- Fri May 18, 2018 9:52 pm
- Forum: Formal Charge and Oxidation Numbers
- Topic: 3.53
- Replies: 4
- Views: 806
Re: 3.53
Yes, that is correct. The formal charge as close to zero as possible and is not canceling out each other.
- Thu May 17, 2018 6:46 pm
- Forum: Electronegativity
- Topic: Relationship between Electronegativity and Ionization Energy
- Replies: 4
- Views: 3126
Re: Relationship between Electronegativity and Ionization Energy
The trend for electronegativity and Ionization energy is the same and because of that I think if the element has lower ionization energy it would also be low electronegativity.
- Tue May 15, 2018 3:21 pm
- Forum: Resonance Structures
- Topic: CN- Resonance structures [ENDORSED]
- Replies: 2
- Views: 1357
CN- Resonance structures [ENDORSED]
Can C have 1 Lone pair and 1 bond? Does this violate the octet rule?
- Mon May 14, 2018 1:34 am
- Forum: Ionic & Covalent Bonds
- Topic: VALENCE ELECTRONS [ENDORSED]
- Replies: 16
- Views: 2043
Re: VALENCE ELECTRONS [ENDORSED]
The number of valence electrons for each group.
- Sun May 13, 2018 2:05 am
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 3011158
Re: Post All Chemistry Jokes Here
Making chemistry puns instead of doing actual work, more like...
- Fri May 11, 2018 9:06 pm
- Forum: Ionic & Covalent Bonds
- Topic: HW problem 3.21
- Replies: 4
- Views: 1314
Re: HW problem 3.21
The ground state electron configuration for Ag+ is [kr] 4d^10 and has no unpaired electrons. The ground state electron configuration for just Ag is [kr] 4d^9 5s^2 but remember we cannot have 4d^9. An electron from 5s^2 will transfer to 4d^9 to become stable. The 4d^9 will become 4d^10. The Ag+ is [k...
- Sun May 06, 2018 8:41 pm
- Forum: Trends in The Periodic Table
- Topic: Difference between Periodic trends [ENDORSED]
- Replies: 4
- Views: 641
Difference between Periodic trends [ENDORSED]
What is the difference between Electron Affinity and Electronegativity both seem too similar? Are there any specific ways to distinguish them?
- Sat May 05, 2018 5:12 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: 2.43
- Replies: 7
- Views: 5420
Re: 2.43
So how do we know when the element’s a “special case”? Do we only write, for example, 4d^10 5s^1 instead of 4d^9 5^2 when the element is near 4d^5 or 4d^10? All the elements in the column Cr and Cu have this special case, but e- configuration should never be 3d^4 and 3d^9 because it should change t...
- Sat May 05, 2018 5:04 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: energy with s,p,d,f
- Replies: 3
- Views: 464
Re: energy with s,p,d,f
It goes from s,p,d,f.
s holds 2 electrons
p holds 6 electrons
d holds 10 electrons
f holds 12 electrons
s holds 2 electrons
p holds 6 electrons
d holds 10 electrons
f holds 12 electrons
- Fri Apr 27, 2018 7:31 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: Why does the 4s orbital come before the 3d?
- Replies: 7
- Views: 1854
Re: Why does the 4s orbital come before the 3d?
The 4s orbitals are lower than 3d.
- Thu Apr 26, 2018 8:06 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 3011158
Re: Post All Chemistry Jokes Here
What was Avogadro’s favorite board game?
Moleoply
Moleoply
- Wed Apr 25, 2018 2:15 am
- Forum: Einstein Equation
- Topic: Chapter 1 Question 25 [ENDORSED]
- Replies: 4
- Views: 710
Re: Chapter 1 Question 25 [ENDORSED]
Yes, that is correct. You would take the E from part a (3.37 x 10^-19) multiply by Avogadro's number (6.022 x 10^23)
- Sun Apr 22, 2018 6:13 pm
- Forum: Significant Figures
- Topic: Use of sigfigs
- Replies: 8
- Views: 911
Re: Use of sigfigs
We have to use sig figs to our final answer to every problem and the right units.
- Fri Apr 20, 2018 10:17 pm
- Forum: Empirical & Molecular Formulas
- Topic: Test #1 Question
- Replies: 7
- Views: 810
Re: Test #1 Question
Can someone please tell me what they got for the first problem on this question. I thought I got it right, but it was marked wrong. (Either the molecular or empirical is fine since I can find out the other one). Thank you! I got that question marked down too because I missed an Oxygen. I believe th...
- Wed Apr 18, 2018 9:18 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Test Number 1
- Replies: 10
- Views: 1210
Re: Test Number 1
The class is not graded on a curve, but there's still two more tests, one midterm, and a final to catch up if you scored low.
- Sun Apr 15, 2018 6:32 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 3011158
Re: Post All Chemistry Jokes Here
Why are chemists great for solving problems? They have all the solutions.
- Sun Apr 15, 2018 6:29 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Tutoring? [ENDORSED]
- Replies: 121
- Views: 240671
Re: Tutoring? [ENDORSED]
The workshop sessions provided by Prof Lavelle are similar to AAP
- Tue Apr 10, 2018 7:48 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 3011158
Re: Post All Chemistry Jokes Here
Chemistry jokes are sodium funny
- Tue Apr 10, 2018 7:44 pm
- Forum: Significant Figures
- Topic: All students read this sig fig post [ENDORSED]
- Replies: 170
- Views: 33596
Re: All students read this sig fig post [ENDORSED]
This forum is very helpful!
- Mon Apr 09, 2018 8:09 pm
- Forum: General Science Questions
- Topic: Rusty on High School Chem [ENDORSED]
- Replies: 347
- Views: 416649
Re: Rusty on High School Chem [ENDORSED]
Makes me feel better seeing many of you feel the same way as me. The first day of the lecture was overwhelming, but the UA step up, workshops, and the online video modules have been really helpful. Hoping that the tests are similar to the practice assessments on the video module.