Search found 64 matches
- Mon Mar 18, 2019 12:02 am
- Forum: General Rate Laws
- Topic: Integral of the Rate Laws [ENDORSED]
- Replies: 1
- Views: 457
Integral of the Rate Laws [ENDORSED]
When a questions asks for us to write down the integrated rate law for the three different orders, are we supposed to show work for how we got to the integrated rate law or can we just simply write down the answer?
- Mon Mar 18, 2019 12:00 am
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Cell Potentials
- Replies: 1
- Views: 599
Cell Potentials
Why do the cell potentials not change even when the reaction its associated with is reversed or halved?
- Sun Mar 17, 2019 4:06 am
- Forum: Concepts & Calculations Using Second Law of Thermodynamics
- Topic: Isothermal, Isobaric, Adiabatic
- Replies: 2
- Views: 635
Isothermal, Isobaric, Adiabatic
I have encountered these terms for processes when studying for thermodynamics but have not seen these specifically outline for the Thermodynamics Outline. Should I know all of these? Only a few? Or none at all for the upcoming final?
- Sat Mar 16, 2019 10:50 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Enthalpy of Fusion
- Replies: 1
- Views: 380
Enthalpy of Fusion
Will we need to know about enthalpy of fusion and the equations associated with it? It didn't seem to be on the outline so I am wondering if this is important or not.
- Sat Mar 16, 2019 10:20 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Disregarding the x in the Denominator
- Replies: 1
- Views: 433
Disregarding the x in the Denominator
When calculating the Ka or Kb, sometimes it will be given in a small number in which we are then allowed to disregard the x in the denominator. Will there ever be a case where we do not disregard the x in the denominator and have to use the quadratic formula or will we not have to concern ourselves ...
- Sat Mar 16, 2019 10:15 pm
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: Final
- Replies: 5
- Views: 956
Final
Is the final split up in a certain way where the material covered after the midterm will comprise a big portion of the test or will the final be split equally for each different outline?
- Sat Mar 16, 2019 10:13 pm
- Forum: Zero Order Reactions
- Topic: Deriving Equations
- Replies: 7
- Views: 1268
Deriving Equations
Will we have to know how to derive each single type of equation for the different orders into other equations or will some be given on the formula sheet?
- Thu Feb 28, 2019 2:24 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: 11.15 6th Edition
- Replies: 2
- Views: 321
11.15 6th Edition
I thought when Gibbs free energy was positive, the reaction is non spontaneous. If so, then why is the answer for this question saying spontaneous even though they gave a positive value for Gibbs free energy or is this just a misunderstanding on my part?
- Thu Feb 28, 2019 5:21 am
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Cell Potential
- Replies: 2
- Views: 343
Cell Potential
Are we expected to know or memorize the different standard reduction potentials of different reactions of elements or will they be given in the problems?
- Thu Feb 28, 2019 3:24 am
- Forum: Balancing Redox Reactions
- Topic: Basic Solutions
- Replies: 3
- Views: 459
Basic Solutions
Is there an easier way or clear set rule in determining which side of the reaction to put the H20 or the OH- or is it determined purely through trial and error? Is it different or the same as compared to an acidic solution?
- Thu Feb 28, 2019 3:18 am
- Forum: Balancing Redox Reactions
- Topic: Acidic Solutions
- Replies: 7
- Views: 903
Acidic Solutions
Is there an easier way to determine which side of the equation to add the H20 or the H when balancing a redox equation in an acidic solution that I am not aware of?
- Wed Feb 27, 2019 11:16 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Cell Diagrams
- Replies: 3
- Views: 457
Cell Diagrams
Can someone explain to me why another element is needed to be put into the cell diagram even when its not in the chemical equations given? Also how would one even go about to choosing that one particular element?
- Wed Feb 27, 2019 11:08 pm
- Forum: Balancing Redox Reactions
- Topic: Oxidation Numbers
- Replies: 3
- Views: 464
Oxidation Numbers
Going into Test 2, are we expected to know all of the natural oxidation numbers for each element or are there few select ones we should already know or have memorized by the test? Or will they be given?
- Wed Feb 27, 2019 11:07 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Redox Reactions and Cell Potentials
- Replies: 2
- Views: 316
Redox Reactions and Cell Potentials
When balancing out redox reactions and equations, why does the cell potential not get multiplied when its respective equation is multiplied to balance out the equation?
- Sat Feb 23, 2019 12:32 am
- Forum: Van't Hoff Equation
- Topic: Deriving Equations
- Replies: 3
- Views: 527
Deriving Equations
Will we know how to derive equations from other equations? My TA did some deriving in discussion so I want to know if we will have to do that.
- Tue Feb 19, 2019 3:20 pm
- Forum: Calculating Standard Reaction Entropies (e.g. , Using Standard Molar Entropies)
- Topic: Test 2
- Replies: 4
- Views: 643
Test 2
Has Lavelle mentioned starting from what day of lecture will be covered for Test 2? Just asking since we stopped halfway into the Thermodynamics outline so I don't know starting from what day of lectures to study.
- Tue Feb 19, 2019 3:19 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Test 2
- Replies: 2
- Views: 248
Test 2
What topics will be covered in Test 2?
- Wed Feb 13, 2019 1:05 pm
- Forum: Entropy Changes Due to Changes in Volume and Temperature
- Topic: Equations
- Replies: 3
- Views: 420
Equations
I know an equation sheet is given to us but some stuff are not that important for the upcoming midterm. Can someone tell me what are some if not all of the main equations we need to know for the midterm just so I am not missing anything important?
- Tue Feb 12, 2019 10:35 pm
- Forum: Entropy Changes Due to Changes in Volume and Temperature
- Topic: 9.13 6th Edition
- Replies: 1
- Views: 209
9.13 6th Edition
For this question, the answer states to just assume 1 mol of the gas to calculate the equation. Will this always be the case if the equation does not explicitly state how many moles we are working with? And will such equations be on the midterm?
- Tue Feb 12, 2019 10:16 pm
- Forum: Entropy Changes Due to Changes in Volume and Temperature
- Topic: Sig Figs
- Replies: 1
- Views: 241
Sig Figs
For the first test, my TA said not to worry too much about sig figs but rather focus on having the correct units. Will the same idea of focusing more on units be more important than sig figs for the midterm as well? Obviously I will try to keep sig figs, but will it matter a whole lot?
- Sun Feb 10, 2019 11:23 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Adiabatic Processes
- Replies: 1
- Views: 281
Adiabatic Processes
The textbook briefly mentioned adiabatic walls and diathermic walls. Is this important information at all for the upcoming midterm or is this relevant at all? Also is this related to adiabatic processes at all or is that something completely different?
- Sun Feb 10, 2019 11:21 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Conversions
- Replies: 4
- Views: 496
Conversions
Will conversions such as 1 L * atm = 101.3 J and other such important conversions be given to us on the front sheet of the test or will such information need to be memorized? If so, what other conversions are deemed important for the upcoming midterm?
- Sun Feb 10, 2019 9:26 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Midterm 2019
- Replies: 9
- Views: 949
Midterm 2019
Up to what outline do we have to study for the upcoming midterm?
- Sun Feb 10, 2019 9:25 pm
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: Midterm
- Replies: 2
- Views: 346
Midterm
Has Lavelle posted yet where the midterm is going to be held at?
- Thu Jan 24, 2019 10:50 am
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Equilibrium Composition
- Replies: 2
- Views: 285
Equilibrium Composition
When using ICE tables and trying to figure out the initial equilibrium composition of a given problem, will the chemical equation or formula of the problem be given always or will we sometimes have to write it out ourselves? I am asking because sometimes I mess up the chemical formula on my own whic...
- Thu Jan 24, 2019 1:41 am
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: Direction of a Reaction
- Replies: 8
- Views: 1035
Direction of a Reaction
When trying to figure out the direction of a reaction using Q, will the problem always give K? Will there ever be a case where K is not given? And if not, how would one go about solving a problem like that?
- Thu Jan 24, 2019 1:27 am
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Test 1
- Replies: 9
- Views: 809
Test 1
For the first test, are there things we should know going into the test that is not given to us? This can range from different formulas to conversions or anything else.
- Wed Jan 23, 2019 5:30 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Calculating pH of Weak Acids and Bases
- Replies: 2
- Views: 324
Calculating pH of Weak Acids and Bases
In the notes, there was a moment where after writing out the ICE chart, the equation Ka = x^2/0.10-x was given. However, because it was a weak acid, the x became negligible and was not considered. Can someone explain why? And can this apply to equations for strong acids and bases or just weak ones?
- Wed Jan 23, 2019 5:24 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Strong Acids and Bases
- Replies: 5
- Views: 557
Strong Acids and Bases
For the upcoming test, will we need to memorize the specific strong acids and strong bases or will they be given to us?
- Wed Jan 23, 2019 5:20 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Calculating Equilibrium Constants
- Replies: 2
- Views: 284
Calculating Equilibrium Constants
In the ICE charts, how are the number of x's determined for each different molecule when calculating the Change in Molarity? Is it determined by the number of moles of the substance in the given equation? I am confused.
- Sun Jan 13, 2019 6:19 pm
- Forum: Ideal Gases
- Topic: Units
- Replies: 3
- Views: 330
Units
There have been several different units that have been floating throughout my discussion and lectures so far. What is torr? What is bar? How do we find these and are these related in anyway?
- Sun Jan 13, 2019 6:16 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: ICE Tables
- Replies: 2
- Views: 327
ICE Tables
Can someone explain to me how ICE tables function in terms of concentration? Like how does one determine the initial concentrations? And how does one determine the change in terms of variables? Sorry if this is too long or confusing.
- Sun Jan 13, 2019 6:12 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Different Concentrations [ENDORSED]
- Replies: 1
- Views: 163
Different Concentrations [ENDORSED]
Is there ever going to be a time where they ask us to find the K for concentration if the problem is given in terms of gas? If so, how would we go about this?
Grades
Did not know where to put this, but I wanted to know what makes up an A+, A, A-, B+, B, B-, etc. in terms of percentages and when grades would be finalized. As a freshman I do not know these things and would like to be informed.
- Fri Dec 07, 2018 3:44 am
- Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
- Topic: Strong Acids
- Replies: 5
- Views: 644
Strong Acids
In discussion today, we went over the 6 strong acids compared to the weak acids. For problems perhaps in the final exam, can we just assume that we will always be trying to find the pH of strong acids? Sorry if this doesn't really make sense.
- Fri Dec 07, 2018 3:37 am
- Forum: Naming
- Topic: Final Exam
- Replies: 2
- Views: 347
Final Exam
For the final exam, will we have to memorize all of the different names or will a chart be given to us?
- Thu Nov 29, 2018 12:00 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Single Electron in Terms of Shape
- Replies: 2
- Views: 295
Single Electron in Terms of Shape
I know that a lone pair is able to alter the final shape of the molecule based off of the electron arrangement, but when we draw the Lewis structure and there is a single electron left alone, is that enough to alter the shape as well or is that power exclusively for lone pairs?
- Thu Nov 29, 2018 4:44 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Resonancy and VSEPR
- Replies: 1
- Views: 176
Resonancy and VSEPR
The textbook discussed briefly about resonancy and how it somehow deals with VSEPR. Does resonnacy matter when determining molecular shape or electron arrangement? If not, should I be worried about this at all for the upcoming test?
- Thu Nov 29, 2018 4:28 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Molecular Shape
- Replies: 2
- Views: 321
Molecular Shape
Are all of the different molecular shapes going to be given to us in a chart or is it something we are expected to memorize for the upcoming test?
- Wed Nov 28, 2018 4:25 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: 4.15 6th Edition
- Replies: 1
- Views: 262
4.15 6th Edition
Can someone explain part b of 4.15? My brain is slipping and I cannot figure it out for the life of me.
- Wed Nov 28, 2018 4:23 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Bond Labeling
- Replies: 1
- Views: 222
Bond Labeling
Is it important to define which bond angle we are using to define its angle. I can see how important it would be for molecules that have varying bonds but for molecules that have bonds that are the same, does it matter? Sorry if this is a dumb question, but I do not want to make silly mistakes on th...
- Wed Nov 28, 2018 4:21 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Bond Angles
- Replies: 5
- Views: 651
Bond Angles
For the most part, are bond angles for the different structures supposed to be memorized or will we be given a chart of some sorts on the test? This might be a dumb question but I am just curious.
- Fri Nov 16, 2018 6:11 pm
- Forum: Hybridization
- Topic: Test 3
- Replies: 5
- Views: 791
Test 3
What pages are we responsible for knowing for the upcoming test? Lavelle sent out an email but for the life of me I could not find it anywhere. He specifically outlined from a section in chapter 3 up to a section in chapter 4. Mind you, this is for the sixth edition of the textbook.
- Fri Nov 16, 2018 5:58 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Bromine Electron Configuration
- Replies: 2
- Views: 2621
Bromine Electron Configuration
One of the questions on the midterm asked for the full ground state electron configuration for bromine. I wrote the answer as [Ar] 3d104s24p5 but I only got half points for it. I'm figuring since it is one electron away from reaching noble gas configuration, that is why I only got half points but I ...
- Fri Nov 16, 2018 5:48 pm
- Forum: Resonance Structures
- Topic: Bond Lengths
- Replies: 2
- Views: 239
Bond Lengths
I have a question about bond lengths. On the past midterm, one of the questions asked us to find the bond lengths in a molecule given two other bond lengths. Are we always supposed to average out the other two bond lengths in such a scenario or is there an important concept I am missing?
- Sun Nov 11, 2018 10:26 pm
- Forum: Einstein Equation
- Topic: Kinetic Energy and Moles
- Replies: 1
- Views: 591
Kinetic Energy and Moles
In Test 2, one of the questions given was to find the total kinetic energy in 5 mol of ejected electrons. I used the Ek = 1/2mV^2 to find the kinetic energy and using the given numbers, my answer came to 1.82 x 10^-24 J. However this answer was wrong. I am wondering if I was supposed to multiply my ...
- Sun Nov 11, 2018 10:18 pm
- Forum: Empirical & Molecular Formulas
- Topic: Midterm
- Replies: 1
- Views: 517
Midterm
I had no idea how to solve what I believe was the second question on the midterm. It asked about gallic acid and we had to find the empirical formula which I wasn't able to do. How would you solve this question? Sorry for being extremely vague.
- Sun Nov 11, 2018 10:12 pm
- Forum: Formal Charge and Oxidation Numbers
- Topic: Formal Charge
- Replies: 12
- Views: 1354
Formal Charge
When we need to draw Lewis structures or even resonance structures, do we need to show calculations done for formal charges in order not to miss points on exams? Will that ever be an issue? The last test asked to show full work so I am wondering if this is necessary.
- Fri Nov 02, 2018 12:26 pm
- Forum: Molarity, Solutions, Dilutions
- Topic: Dilution Units
- Replies: 1
- Views: 496
Dilution Units
In terms of dilution, will the solute being dissolved in the solution always be in terms of moles for its units? I got marked down on the first test for leaving my answer in grams even when it asked for grams, so I just want to know to clarify things going forward. In addition, what units will the s...
- Fri Nov 02, 2018 12:22 pm
- Forum: Quantum Numbers and The H-Atom
- Topic: Degeneracy Formula
- Replies: 1
- Views: 254
Degeneracy Formula
During my discussion the TA went over degeneracy and basically summed it up to the equation 2l + 1 to find how many degenerate orbitals there are. Besides this formula, if it even is correct or relevant, is there anything else important we need to understand conceptually about degeneracy?
- Fri Nov 02, 2018 12:07 pm
- Forum: Bond Lengths & Energies
- Topic: Midterm
- Replies: 1
- Views: 180
Midterm
Just wondering, up to what section will we have to know for the upcoming midterm in terms of the sixth edition of the textbook?
- Mon Oct 29, 2018 12:13 am
- Forum: Quantum Numbers and The H-Atom
- Topic: Degeneracy
- Replies: 8
- Views: 1461
Degeneracy
Can someone explain to me the concept of degeneracy? A friend tried explaining it to me but he made it seem more complicated. Also, I don't know if I am reading it right, but I don't understand what the textbook says.
- Mon Oct 29, 2018 12:08 am
- Forum: Properties of Light
- Topic: Photoelectric Effect
- Replies: 7
- Views: 973
Photoelectric Effect
In terms of the photoelectric effect, just to make sure I fully understand this concept, if the quantity of electrons increases, would the intensity of the light also increase due to the photoelectric effect?
- Mon Oct 29, 2018 12:05 am
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: Electron in Center of Orbital
- Replies: 1
- Views: 238
Electron in Center of Orbital
I do not understand this concept at all. I read over a question where it asks what are the chances that an electron is in the center of an orbital. How would we calculate this if we could at all?
- Sun Oct 28, 2018 11:59 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: 2.25 6th Edition
- Replies: 2
- Views: 408
2.25 6th Edition
Hello, the question asks for the number of electrons in an orbital. Since the maximum number fo electrons in increasing orbital order is 2 , 4, 10, 14 , etc., do we count the orbitals in just the orbital or the ones before it as well?
- Wed Oct 24, 2018 11:08 pm
- Forum: Photoelectric Effect
- Topic: Example 1.5 Part C in 6th Edition
- Replies: 1
- Views: 322
Example 1.5 Part C in 6th Edition
In the textbook there is an example of analyzing the photoelectric effect. The first two parts I understand but I don't understand part C conceptually. The questions asks us: "To find the longest wavelength of radiation that is able to eject an electron." They go on to set Ek = 0 which I d...
- Sun Oct 21, 2018 2:39 am
- Forum: Properties of Light
- Topic: Test 2
- Replies: 7
- Views: 677
Re: Test 2
Thanks! That helps a lot.
- Sun Oct 21, 2018 2:37 am
- Forum: Properties of Light
- Topic: 1.9 6th Edition
- Replies: 1
- Views: 130
1.9 6th Edition
I figured out how to do the calculations for all of the missing information needed for the table. However I am confused as to how they filled out the activities for each individual section. I know the activities are listed in the problem, but is that something we should be looking up, common sense, ...
- Sun Oct 21, 2018 2:32 am
- Forum: Properties of Light
- Topic: Test 2
- Replies: 7
- Views: 677
Test 2
What are we responsible to know for this upcoming test? I know there is a basic outline for what we need to know for this week's test but sometimes not everything will be covered.
- Fri Oct 12, 2018 9:06 pm
- Forum: Limiting Reactant Calculations
- Topic: Test 1
- Replies: 5
- Views: 670
Test 1
I have several questions about the first test. Is there a chance to get partial credit for every question on the test? What if our answers for the problems are off by a few decimals because of rounding differences or using different values for elements? Also a very specific question, for the molarit...
- Fri Oct 12, 2018 8:53 pm
- Forum: Accuracy, Precision, Mole, Other Definitions
- Topic: E 27 Sixth Edition
- Replies: 2
- Views: 618
E 27 Sixth Edition
For the first portion of E 25, they ask for formula units? How would you find this and will this concept be in future tests?
- Fri Oct 12, 2018 8:52 pm
- Forum: Accuracy, Precision, Mole, Other Definitions
- Topic: E 21 Sixth Edition
- Replies: 1
- Views: 579
E 21 Sixth Edition
I understand portion a of 21 but I don't understand what specifically they are asking for part d. When they ask for N2 molecules, would you just divide by 2 of what you got for N atoms? Can someone explain or am I just overthinking this?
- Fri Oct 12, 2018 8:38 pm
- Forum: Significant Figures
- Topic: Problem G5
- Replies: 2
- Views: 549
Re: Problem G5
62.5 mL should be the correct answer unless I am looking at a different version. Using the molarity equation and rearranging it to find volume of solution (V), you get (4.98 x 10^-3 mol of CO3) / (0.07967 mol/L of Na2CO3) = 6.25 x 10^-2 or 62.5 mL.
- Fri Oct 12, 2018 8:17 pm
- Forum: SI Units, Unit Conversions
- Topic: What Unit of Mass to Use?
- Replies: 5
- Views: 994
What Unit of Mass to Use?
I'm confused as to what unit I should be using for mass. During the lecture, Lavelle stated that the SI unit of mass was "kilogram", but a majority of the answers to homework problems come out in terms of "grams". Can someone explain?