## Search found 62 matches

Fri Mar 15, 2019 1:12 am
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Reducing/Oxidizing Power
Replies: 7
Views: 383

### Re: Reducing/Oxidizing Power

Does a higher oxidizing power (more power to oxidize another atom) also mean its most likely to gain electrons/become reduced?
Fri Mar 15, 2019 1:09 am
Forum: First Order Reactions
Topic: Order of reactions plots
Replies: 2
Views: 97

### Re: Order of reactions plots

These are for the integrated rate laws correct?
Fri Mar 15, 2019 1:09 am
Forum: Arrhenius Equation, Activation Energies, Catalysts
Topic: Arrehnius Equation
Replies: 2
Views: 78

### Re: Arrehnius Equation

It is also similar to the van't hoff equation which I think is given, so you can remember it that way.
Sat Mar 09, 2019 10:25 pm
Forum: Zero Order Reactions
Topic: Half Life and k
Replies: 11
Views: 616

### Re: Half Life and k

Will we be required to know how to derive half-life equations for each order of reaction
Sat Mar 09, 2019 10:24 pm
Forum: General Rate Laws
Topic: integrals
Replies: 8
Views: 312

### Re: integrals

^the resources are helpful, but I don't think we will be required to know exactly how to derive using calculus since it wasn't a prereq for this class, just as long you understand the concepts behind it
Thu Mar 07, 2019 9:59 am
Forum: General Rate Laws
Topic: 7A.1 7th edition
Replies: 1
Views: 70

### Re: 7A.1 7th edition

I don't have 7th edition for the textbook, do you think you could specify which problem you are talking about?
Sun Mar 03, 2019 3:37 pm
Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
Topic: standard cell potential negative and positive
Replies: 2
Views: 78

### Re: standard cell potential negative and positive

This corresponds with the equation delta G=-nFE because if the cell potential is positive then delta G is negative which makes it spontaneous, and if cell potential is negative, delta G is positive making the reaction non-spontaneous.
Sun Mar 03, 2019 3:36 pm
Forum: Method of Initial Rates (To Determine n and k)
Topic: Determine n
Replies: 3
Views: 149

### Re: Determine n

Which equation are you talking about? For example, if you are talking about n in the delta G=-nFE, then n is the number of electrons.
Sun Mar 03, 2019 3:35 pm
Forum: Balancing Redox Reactions
Topic: Acidic vs basic solutions
Replies: 10
Views: 362

### Re: Acidic vs basic solutions

For balancing half reactions in both acidic and basic solutions, first balance the elements that are not Hydrogen or Oxygen. Then balance the O atoms by adding H20. For the next step: in acidic solution, balance H by using H+. But In basic solution, balance H by using H20 to the side of each half re...
Sat Feb 23, 2019 2:20 pm
Forum: Gibbs Free Energy Concepts and Calculations
Topic: Spontaneity
Replies: 2
Views: 97

### Re: Spontaneity

Can spontaneity be determined by solely looking at the cell potential value?
Sat Feb 23, 2019 2:19 pm
Forum: Gibbs Free Energy Concepts and Calculations
Topic: clarification on equations for delta G
Replies: 2
Views: 99

### Re: clarification on equations for delta G

There is also an equation that consists of delta G and delta G naught together and are distinguished through the reaction quotient Q?
Sat Feb 23, 2019 2:18 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Salt bridge
Replies: 3
Views: 128

### Re: Salt bridge

Do the two vertical lines in the notation represent the salt bridge?
Sat Feb 16, 2019 3:10 pm
Forum: Third Law of Thermodynamics (For a Unique Ground State (W=1): S -> 0 as T -> 0) and Calculations Using Boltzmann Equation for Entropy
Topic: Degeneracy
Replies: 4
Views: 342

### Re: Degeneracy

So the lowest level of degeneracy we will encounter is 1?
Sat Feb 16, 2019 3:08 pm
Forum: Gibbs Free Energy Concepts and Calculations
Topic: Test 2
Replies: 3
Views: 152

### Re: Test 2

On the class website he said "Test 2 covers all topics on Gibbs free energy and electrochemistry up to the Nernst equation."
Sat Feb 16, 2019 3:07 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: When does delta U equal zero?
Replies: 17
Views: 1842

### Re: When does delta U equal zero?

Do we assume isothermal, reversible, and at equilibrium are all synonymous in this class?
Sat Feb 09, 2019 10:43 am
Forum: Concepts & Calculations Using Second Law of Thermodynamics
Topic: Motion and Entropy/Enthalpy
Replies: 3
Views: 135

### Re: Motion and Entropy/Enthalpy

Are entropy and enthalpy directly proportional?
Sat Feb 09, 2019 10:41 am
Forum: Entropy Changes Due to Changes in Volume and Temperature
Topic: Predict entropy change
Replies: 3
Views: 124

### Re: Predict entropy change

So we look only at gas moles and not at the changes in the other phase moles?
Sat Feb 09, 2019 10:38 am
Forum: Concepts & Calculations Using First Law of Thermodynamics
Topic: Gas constant, R
Replies: 3
Views: 133

### Re: Gas constant, R

I think the best way to look at it is what units you want the answer to be in. If you need the answer in joules, it's best to use 8.314 and make sure to convert all the factor in the equation to joules. For example the conversion factor between atm.L to J is 101.325.
Fri Feb 01, 2019 9:54 pm
Forum: Phase Changes & Related Calculations
Topic: Chemical potential energy
Replies: 4
Views: 113

### Re: Chemical potential energy

Will we get the same answer even if we do the long method of all breaking all the reactant bonds and forming all the product bonds?
Fri Feb 01, 2019 9:51 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: Different Kinds of Symptoms
Replies: 6
Views: 209

### Re: Different Kinds of Symptoms

Is insulation and the lack of it also a good indicator of the type of system it is?
Fri Feb 01, 2019 9:47 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Enthalpies
Replies: 5
Views: 158

### Re: Enthalpies

So when there's an increase in enthalpy, heat was added to the system and vice versa?
Fri Jan 25, 2019 6:32 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: Quiz #1 This friday
Replies: 5
Views: 282

### Re: Quiz #1 This friday

If you still need some practice or clarification, I find it helpful to watch videos online like Khan Academy.
Fri Jan 25, 2019 6:28 pm
Forum: Phase Changes & Related Calculations
Topic: Modules
Replies: 17
Views: 421

### Re: Modules

The videos he posts with them are very similar to the lectures in class too so if you forget to write something down or miss something, those videos are very helpful.
Fri Jan 25, 2019 6:28 pm
Forum: Phase Changes & Related Calculations
Topic: Calculations for phase changes Adams Disc 1A
Replies: 2
Views: 93

### Re: Calculations for phase changes Adams Disc 1A

I believe Professor Lavelle told us that most equations and constants we need to know will be given in the equation sheet we are provided with for every test.
Sun Jan 20, 2019 4:09 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Autoprotolysis
Replies: 3
Views: 93

### Re: Autoprotolysis

I also believe it is significant because when solving weak base/weak acid problems, you can convert from Ka to Kb using the Kw constant = [H3O+][OH-] = 1.0 x 10^-14
Sun Jan 20, 2019 4:06 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: 5D.5 in 7th Ed
Replies: 1
Views: 118

### Re: 5D.5 in 7th Ed

I believe to get Ka you need to do 10^(-pka). Once you get the value for Ka, you divide 14 (KW) by the Ka in order to get Kb. If this is giving you the wrong answer you can also try this: 14-pka=pkb. Then do 10^(-pkb) in order to get the Kb value. Essentially both ways should get you the same answer...
Sun Jan 20, 2019 4:02 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: The Conjugate Seesaw
Replies: 13
Views: 379

### Re: The Conjugate Seesaw

I had a similar question and found a post on chemistry community for it:
viewtopic.php?t=8560
Hope it helps!
Fri Jan 11, 2019 7:47 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Q and K
Replies: 13
Views: 300

### Re: Q and K

Should we specify Qc And Qp just like we differentiate between Kc and Kp?
Fri Jan 11, 2019 7:45 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Kc and Kp
Replies: 12
Views: 386

### Kc and Kp

Are solids and liquids not included in calculating Kc AND Kp or just Kc?
Fri Jan 11, 2019 7:35 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Mole Ratio with a Solid [ENDORSED]
Replies: 3
Views: 92

### Re: Mole Ratio with a Solid[ENDORSED]

Is it the same case for liquids as it is for solids?
Tue Dec 04, 2018 5:42 pm
Forum: Naming
Topic: writing formulas
Replies: 2
Views: 77

### Re: writing formulas

Can someone also explain why we right H2O as OH2 in the drawings?
Tue Dec 04, 2018 5:38 pm
Forum: Interionic and Intermolecular Forces (Ion-Ion, Ion-Dipole, Dipole-Dipole, Dipole-Induced Dipole, Dispersion/Induced Dipole-Induced Dipole/London Forces, Hydrogen Bonding)
Topic: Hydrogen Bonds
Replies: 14
Views: 378

### Re: Hydrogen Bonds

So molecules that have hydrogen bonding also have dipole-dipole and ldf as well?
Tue Dec 04, 2018 5:36 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: polarity
Replies: 11
Views: 290

### Re: polarity

So just to confirm, does polarity have anything to do with if there are single, double, or triple bonds?
Tue Dec 04, 2018 5:33 pm
Forum: Acidity & Basicity Constants and The Conjugate Seesaw
Topic: Significance of Equilibrium Constants
Replies: 2
Views: 137

### Re: Significance of Equilibrium Constants

The notes in the past lecture said that stronger acids have higher Ka values.
Tue Dec 04, 2018 5:26 pm
Forum: Lewis Acids & Bases
Topic: Textbook section on acids
Replies: 3
Views: 178

### Re: Textbook section on acids

Does anyone know what the above sections correspond to in the 7th edition.
Sat Dec 01, 2018 10:09 pm
Forum: Naming
Topic: Roman Numeral
Replies: 5
Views: 217

### Re: Roman Numeral

An example is [Fe(CN)₆]4−. The oxidation state of the compound is 4- and the number for CN is -1 for 6 molecules so it is -6. You then subtract -6 from -4 to get the +2 oxidation number for Fe.
Sat Dec 01, 2018 10:03 pm
Forum: Dipole Moments
Topic: Dipole moments and resonances
Replies: 3
Views: 193

### Re: Dipole moments and resonances

I think the patterns for such molecules would follow that of SO3, but I would search for exceptions just in case so you don't make generalizations.
Sat Dec 01, 2018 9:59 pm
Forum: Interionic and Intermolecular Forces (Ion-Ion, Ion-Dipole, Dipole-Dipole, Dipole-Induced Dipole, Dispersion/Induced Dipole-Induced Dipole/London Forces, Hydrogen Bonding)
Topic: Distinguishing between the different intermolecular forces
Replies: 9
Views: 416

### Re: Distinguishing between the different intermolecular forces

Which edition are you looking at? I'm think this information is in the textbook for edition 6.
Sun Nov 25, 2018 12:31 pm
Forum: Hybridization
Topic: Test 3
Replies: 13
Views: 298

### Re: Test 3

So does identifying molecular shape include knowing how to identify electron density shape as well?
Sun Nov 25, 2018 12:28 pm
Forum: Lewis Structures
Topic: Lewis Structures
Replies: 2
Views: 118

### Re: Lewis Structures

Don't forget to account for the plus charge on the molecule as well.
Sun Nov 25, 2018 12:26 pm
Forum: Interionic and Intermolecular Forces (Ion-Ion, Ion-Dipole, Dipole-Dipole, Dipole-Induced Dipole, Dispersion/Induced Dipole-Induced Dipole/London Forces, Hydrogen Bonding)
Topic: Distinguishing between the different intermolecular forces
Replies: 9
Views: 416

### Re: Distinguishing between the different intermolecular forces

So regardless of the molecule being ionic or covalent, it has LDF?
Sun Nov 18, 2018 9:06 pm
Forum: General Science Questions
Topic: Thanksgiving Week
Replies: 8
Views: 408

### Re: Thanksgiving Week

For the people whose discussions are cancelled Thursday and Friday, can we attend any discussions Monday-Wednesday?
Sun Nov 18, 2018 9:05 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Molecular Shape vs. Electron Geometry
Replies: 4
Views: 172

### Re: Molecular Shape vs. Electron Geometry

So is this an easy way to look at it: electron geometry/arrangement takes into account lone pairs of the central atom whereas molecular shape simply considers the shared bonds?
Sun Nov 18, 2018 9:03 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Sigma/Pi bonds
Replies: 7
Views: 288

### Re: Sigma/Pi bonds

So just to confirm there is no more than one sigma bond in any bond/atom interaction?
Sat Nov 10, 2018 4:28 pm
Forum: Interionic and Intermolecular Forces (Ion-Ion, Ion-Dipole, Dipole-Dipole, Dipole-Induced Dipole, Dispersion/Induced Dipole-Induced Dipole/London Forces, Hydrogen Bonding)
Topic: Hydrogen Bonds
Replies: 14
Views: 378

### Re: Hydrogen Bonds

So hydrogen bonds consist of three different intermolecular forces: hydrogen bond, dipole-dipole, and london?
Sat Nov 10, 2018 4:19 pm
Forum: Interionic and Intermolecular Forces (Ion-Ion, Ion-Dipole, Dipole-Dipole, Dipole-Induced Dipole, Dispersion/Induced Dipole-Induced Dipole/London Forces, Hydrogen Bonding)
Topic: Induced Dipole-Induced Dipole names?
Replies: 4
Views: 296

### Re: Induced Dipole-Induced Dipole names?

I think the other names were London, Dispersion and Van Der Waals.
Hope this helps!
Sat Nov 10, 2018 4:18 pm
Forum: Dipole Moments
Topic: Dipole Moments
Replies: 4
Views: 120

### Re: Dipole Moments

It has to do with the electronegativity difference between atoms. Molecules with atoms of same electronegativity have no dipole movement whereas a molecule such as HF has dipole movement due the electronegativity difference.
Thu Nov 01, 2018 11:56 pm
Forum: Trends in The Periodic Table
Topic: Ex 2.93
Replies: 2
Views: 126

### Re: Ex 2.93

As said above it's best to review the trend of atomic radius first. Then review which element is the cation and which one is the anion, based on that you can figure out if the atom increased or decreased in size.
Thu Nov 01, 2018 11:52 pm
Forum: Trends in The Periodic Table
Topic: Diagonal Relationship
Replies: 3
Views: 165

### Re: Diagonal Relationship

Diagonal relationships also exist within other trends and certain pairs of elements I think.
Thu Nov 01, 2018 11:38 pm
Forum: Ionic & Covalent Bonds
Topic: Valence electron
Replies: 4
Views: 132

### Re: Valence electron

The transition metals don't have a traditional method to identify valence electrons like the other groups, but I don't think we have gone over in class how to determine how many valence electrons each transition metal has.
Wed Oct 24, 2018 4:34 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Electron Configurations for Chromium and Copper
Replies: 2
Views: 67

### Re: Electron Configurations for Chromium and Copper

So in these cases, I believe a completely full or half full d sub-level is more stable than a partially filled level. So an electron from the 4s orbital is 'excited' and rises to a 3d orbital. For example for copper it goes from 3d9 to 3d10 and the s orbital goes from 4s2 to 4s1. Hope that helps!
Wed Oct 24, 2018 4:29 pm
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: HW 1.15
Replies: 1
Views: 97

### Re: HW 1.15

Because the question says it is the emission of energy, meaning the release of energy we can assume the initial energy level is n=3 and the final is n=1 because energy is released when an electron falls from a higher energy level to a lower.
Wed Oct 24, 2018 4:27 pm
Forum: Photoelectric Effect
Topic: HW 1.3
Replies: 4
Views: 258

### Re: HW 1.3

I believe C is true because when frequency decreases, the wavelength increases (it sort of drags out the wave). This in turn decreases the slope of the wave which correlates to the extent of change in the electrical field. Hope this helps!
Fri Oct 19, 2018 3:10 pm
Forum: Properties of Light
Topic: Equations
Replies: 7
Views: 180

### Re: Equations

Will we be required to know how to derive De Broglie's Equation?
Fri Oct 19, 2018 11:28 am
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: Balmer series
Replies: 1
Views: 78

### Re: Balmer series

Hey! So this question was actually discussed in chemistry community before so I'm posting the link below, hope it helps! https://lavelle.chem.ucla.edu/forum/viewtopic.php?t=5786 In short, you know n1=2 because it is a Balmer series and n2=7 by counting. Use the equation E = -hR/n^2 you can find the ...
Fri Oct 19, 2018 11:19 am
Forum: Properties of Electrons
Topic: Rydberg Formula 1.13
Replies: 3
Views: 165

### Re: Rydberg Formula 1.13

So you can use 1.097 x 10^7 as the Rydberg constant but when using it, you have to use a different Rydberg equation. So it might be easier to stick with the constant and equation we were given in class.
Sat Oct 13, 2018 5:55 pm
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: Negative v. Positive when calculating energy
Replies: 8
Views: 276

### Re: Negative v. Positive when calculating energy

It is negative because the electron's energy has decreased and the energy is released as electromagnetic radiation, hope this helps!
Sat Oct 13, 2018 5:31 pm
Forum: Properties of Electrons
Topic: Spectral Lines (Balmer Series & Lyman Series)
Replies: 3
Views: 97

### Re: Spectral Lines (Balmer Series & Lyman Series)

I am also confused on this topic. In the HW problem 11 for chapter 1, we are asked to compare two figures and their spectral lines. I'm not sure where to start with this question and what exactly is common to their lines?
Sat Oct 13, 2018 5:06 pm
Forum: Properties of Light
Topic: Wavelength Units
Replies: 5
Views: 176

### Wavelength Units

When answering questions about wavelengths, is it best to write the units as meters or nanometers?
Wed Oct 03, 2018 11:55 pm
Forum: Molarity, Solutions, Dilutions
Topic: 6th Edition, Problem G.21
Replies: 1
Views: 57

### Re: 6th Edition, Problem G.21

Yes, you're right! It is based on the ratio of atoms in each molecule, you find how many moles of K there are in each of the three molecules and then add them up to get the total amount of moles of K.
Hope this helps!
Wed Oct 03, 2018 11:37 pm
Forum: Balancing Chemical Reactions
Topic: Net Ionic Equation?
Replies: 2
Views: 72

### Net Ionic Equation?

On fundamental M question 9a edition 6, we are asked to write a net ionic equation. Is this going to be on our first test?
Wed Oct 03, 2018 11:24 pm
Forum: SI Units, Unit Conversions
Topic: Homework Question Edition 6 E1
Replies: 4
Views: 224

### Re: Homework Question Edition 6 E1

We multiply 144 by 2 because 144pm is the radius and we want the diameter of the atom.