## Search found 62 matches

Sun Feb 24, 2019 11:51 pm
Forum: Balancing Redox Reactions
Topic: E dependency on moles
Replies: 2
Views: 57

### Re: E dependency on moles

If you think about the definition of an intensive property where the value does not depend on anything else (anything external), then you can see that anything with an intensive property won't depend on moles. E is an intensive property, so it checks out.
Sun Feb 24, 2019 11:49 pm
Forum: Balancing Redox Reactions
Topic: Redox Rxns in Acidic and Basic Solutions
Replies: 6
Views: 128

### Re: Redox Rxns in Acidic and Basic Solutions

The problem would have to tell us.
Sun Feb 24, 2019 11:48 pm
Forum: Environment, Fossil Fuels, Alternative Fuels
Topic: Why energy crisis?
Replies: 8
Views: 2510

### Re: Why energy crisis?

We can't use all forms of energy in the same way.
Sun Feb 24, 2019 11:47 pm
Forum: Gibbs Free Energy Concepts and Calculations
Topic: Free Energy is a state function?
Replies: 5
Views: 92

### Re: Free Energy is a state function?

The path doesn't affect the end value of free energy, so we can just add and subtract them up.
Sun Feb 24, 2019 11:46 pm
Forum: Van't Hoff Equation
Topic: Test 2
Replies: 3
Views: 290

### Re: Test 2

Just check the rest of outline 4 that we didn't cover on the midterm!
Sun Feb 24, 2019 11:44 pm
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: Spontaneous and unstable
Replies: 4
Views: 130

### Spontaneous and unstable

What's the difference between spontaneous and unstable?
Sun Feb 24, 2019 11:44 pm
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: Test 3
Replies: 14
Views: 321

### Re: Test 3

Follow the outlines and do whatever is on the homework! That consistently works for me when I'm studying for tests.
Sun Feb 24, 2019 11:43 pm
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: Test 2
Replies: 1
Views: 84

### Test 2

In the sixth edition of the textbook, what problems should we go up to for test 2? (When do the Nerst Equation problems start?
Tue Feb 12, 2019 2:25 am
Forum: Administrative Questions and Class Announcements
Replies: 179
Views: 8642

Mya Majewski 1L wrote:for question 8, isn't the answer going to be Kb x 3^8?

the formula is S=KblnW, so you need to take the natural log of 3 to the 8th power
Tue Feb 12, 2019 1:54 am
Forum: Administrative Questions and Class Announcements
Replies: 179
Views: 8642

For #6, how do we know that work is equal to 0?
Tue Feb 12, 2019 1:35 am
Forum: Administrative Questions and Class Announcements
Replies: 179
Views: 8642

I'm confused on #4, too. What equations are relevant?
Sat Feb 09, 2019 12:20 pm
Forum: Calculating Work of Expansion
Topic: Derivatives and Integrals
Replies: 5
Views: 135

### Derivatives and Integrals

Will we need to use derivatives and integrals on the midterm? Or did we just do that to derive the equations that we use now?
Sat Feb 09, 2019 12:19 pm
Forum: Thermodynamic Systems (Open, Closed, Isolated)
Topic: Systems
Replies: 6
Views: 372

### Systems

What's a quick way to know if something is open, closed, or isolated? It gets confusing.
Sat Feb 09, 2019 12:18 pm
Forum: Calculating Standard Reaction Entropies (e.g. , Using Standard Molar Entropies)
Topic: Midterm
Replies: 1
Views: 70

### Midterm

What homework problems should I go up to in outline 4 for the midterm if I'm using the sixth edition textbook? I know we stop before Gibb's Free Energy, but I'm not sure which homework problem that corresponds to.
Wed Jan 30, 2019 11:59 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: increasing pressure, what happens to concentration?
Replies: 10
Views: 254

### Re: increasing pressure, what happens to concentration?

Take volume into account. The reaction will favor the side with fewer moles.
Wed Jan 30, 2019 11:58 pm
Forum: Ideal Gases
Topic: derivatives and integrals
Replies: 6
Views: 329

### Re: derivatives and integrals

He gave us two equations that were the same thing, just in different forms. The integral and the other equation mean the same thing; it's just different math.
Wed Jan 30, 2019 11:56 pm
Forum: Phase Changes & Related Calculations
Topic: State Properites
Replies: 7
Views: 161

### Re: State Properites

When dealing with work and heat, you have to take into account every step in the process of the change, not just the final and initial values.
Wed Jan 30, 2019 11:53 pm
Forum: Phase Changes & Related Calculations
Topic: J vs. kJ
Replies: 9
Views: 214

### Re: J vs. kJ

It shouldn't matter unless they specify! Make sure you know what the question is asking though.
Wed Jan 30, 2019 11:52 pm
Forum: Phase Changes & Related Calculations
Topic: Week 4 Homework
Replies: 12
Views: 299

### Re: Week 4 Homework

It really depends on your TA, but to be safe, just do material that we learned this week or las week.
Wed Jan 30, 2019 11:51 pm
Forum: Phase Changes & Related Calculations
Topic: Test #1
Replies: 11
Views: 254

### Re: Test #1

Yes, we all get them back this week!
Wed Jan 23, 2019 3:41 pm
Forum: Ideal Gases
Topic: Ideal Gas Law
Replies: 7
Views: 194

### Ideal Gas Law

When can we use the ideal gas law?
Wed Jan 23, 2019 3:40 pm
Forum: Phase Changes & Related Calculations
Topic: How to tell acids and bases
Replies: 8
Views: 203

### Re: How to tell acids and bases

In chem14a, we drew lewis dot structures, and through that, we saw if something was an acid or a base.
Wed Jan 23, 2019 3:38 pm
Forum: Phase Changes & Related Calculations
Topic: Endothermic or Exothermic
Replies: 20
Views: 649

### Re: Endothermic or Exothermic

Condensation is exothermic because it releases heat. You see this in real life when you have a cold drink and condensation forms water droplets on the side of the cup.
Tue Jan 15, 2019 3:33 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: test 1 [ENDORSED]
Replies: 7
Views: 236

### Re: test 1[ENDORSED]

The test will probably cover acids and bases, too. I think it will most likely cover lectures from the first two weeks.
Tue Jan 15, 2019 3:32 pm
Forum: General Science Questions
Topic: Autoprotolysis
Replies: 3
Views: 277

### Re: Autoprotolysis

If you break down the word into parts, you can deduce the meaning, too! Auto would indicate that autoprotolysis happens itself, hinting that it involves the same molecule. Proto can tell you that it involves protons.
Tue Jan 15, 2019 3:29 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Changes to K value
Replies: 9
Views: 170

### Re: Changes to K value

Only changes in temperature change the K value.
Sun Jan 13, 2019 3:59 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Heterogeneous and homogeneous equilibria [ENDORSED]
Replies: 8
Views: 188

### Re: Heterogeneous and homogeneous equilibria[ENDORSED]

We have to keep in mind if any of the reactants or products are solids or liquids because we don't factor them in when we calculate the equilibrium constant, K.
Sun Jan 13, 2019 3:57 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: equations
Replies: 10
Views: 150

### Re: equations

You can tell what are reactants or products if you know the equation for the chemical reaction. If the problem doesn't just straight out give it to you, you can figure it out yourself based on context clues from the problem.
Sun Jan 13, 2019 3:56 pm
Forum: Ideal Gases
Topic: When to Use PV=nRT
Replies: 8
Views: 284

### Re: When to Use PV=nRT

For this class, I think we just need to use this equation when we convert from concentration to partial pressure, so when you are solving for Kc, you need concentrations and when you are solving for Kp, you need partial pressures.
Wed Jan 09, 2019 10:27 am
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Difference between brackets and parentheses?
Replies: 4
Views: 297

### Re: Difference between brackets and parentheses?

Other answers explained the reasoning, but basically you use brackets when solving for Kc and use parentheses when solving for Kp.
Wed Jan 09, 2019 10:25 am
Forum: Equilibrium Constants & Calculating Concentrations
Topic: K
Replies: 4
Views: 64

### Re: K

Kc is used when the units of the equilibrium concentrations are moles per liter. Kp is used when using partial pressure. It’s basically the same thing but with different units.
Wed Jan 09, 2019 10:22 am
Forum: Student Social/Study Group
Topic: New to Lavelle
Replies: 32
Views: 3706

### Re: New to Lavelle

I honestly find all of his resources helpful, so I do all the problems in the book, watch the modules, and go to workshops when I need extra help on a topic. That’s just generally how I prepare for a test in his class.
Wed Dec 05, 2018 12:47 am
Forum: Shape, Structure, Coordination Number, Ligands
Topic: chelates
Replies: 5
Views: 160

### Re: chelates

Chelates are in the shape of rings, making them pretty easy to distinguish.
Wed Dec 05, 2018 12:46 am
Forum: Naming
Topic: Knowing oxidation states
Replies: 11
Views: 213

### Re: Knowing oxidation states

I think it is safe to just study the sheet posted on Lavelle's website because it has a lot of common ligands that we should probably know.
Mon Nov 26, 2018 11:18 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Lone PR and Bonding PR
Replies: 2
Views: 63

### Lone PR and Bonding PR

Which lone pair and bonding pair shapes do we need to know? I know there are bent and trigonal pyramidal, but which other ones would we need to know for test 3?
Mon Nov 26, 2018 11:27 am
Forum: Bond Lengths & Energies
Topic: How to Measure Bond Lengths
Replies: 4
Views: 120

### Re: How to Measure Bond Lengths

We only need to know the trends, not the exact bond lengths.
Mon Nov 26, 2018 11:26 am
Forum: Dipole Moments
Topic: dipole
Replies: 6
Views: 191

### Re: dipole

Dipoles can cancel each other out so the molecule would not be polar.
Mon Nov 26, 2018 11:25 am
Forum: Coordinate Covalent Bonds
Topic: Coordinate Covalent Bond Definition
Replies: 14
Views: 759

### Re: Coordinate Covalent Bond Definition

That definition seems correct. It's basically identical to the one from lecture today!
Mon Nov 26, 2018 11:23 am
Forum: Naming
Topic: Naming and Polyatomic Ions
Replies: 6
Views: 493

### Re: Naming and Polyatomic Ions

im pretty sure you can use them interchangeably
Mon Nov 26, 2018 11:22 am
Forum: Naming
Topic: Naming
Replies: 5
Views: 337

### Re: Naming

bond angles for pentagona bipyramidal are 72 and 90 degrees
Mon Nov 26, 2018 11:21 am
Forum: Naming
Topic: Naming
Replies: 9
Views: 514

### Re: Naming

ions are charged
Thu Nov 15, 2018 2:20 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 bonding
Replies: 11
Views: 299

### Re: hydrogen bonding

Hydrogen bonding takes more energy to break because it is stronger than most intermolecular forces.
Thu Nov 15, 2018 2:18 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: Polar and Dipole
Replies: 3
Views: 95

### Polar and Dipole

What's the relationship between polarization and dipole moments? What's the difference?
Thu Nov 15, 2018 2:17 pm
Forum: Sigma & Pi Bonds
Topic: Sigma and Pi bonds
Replies: 4
Views: 132

### Sigma and Pi bonds

How do we figure out if i bond is a sigma bond or a pi bond?
Wed Nov 07, 2018 3:06 pm
Forum: Dipole Moments
Topic: HCl
Replies: 6
Views: 131

### Re: HCl

HCl has a permanent dipole moment because H becomes slightly positive because it gives its electron to Cl which becomes slightly negative.
Wed Nov 07, 2018 3:04 pm
Forum: Ionic & Covalent Bonds
Topic: Metalloids
Replies: 2
Views: 83

### Metalloids

What type of bonds do metalloids form?
Wed Nov 07, 2018 3:04 pm
Forum: Octet Exceptions
Topic: List of octect exceptions
Replies: 6
Views: 225

### List of octect exceptions

Can someone provide a brief, undetailed list of the octet exceptions we have learned so far?
Thu Nov 01, 2018 3:26 pm
Forum: Resonance Structures
Topic: Resonance
Replies: 8
Views: 238

### Re: Resonance

Double bonds are stronger than single bonds and require more energy to break. Triple bonds are stronger than double bonds. They all have different lengths because they have different strengths.
Thu Nov 01, 2018 3:23 pm
Forum: Ionic & Covalent Bonds
Topic: Covalent Bonds
Replies: 16
Views: 451

### Re: Covalent Bonds

Non metals cannot form cations; instead, they form anions and metals form cations.
Thu Nov 01, 2018 3:22 pm
Forum: Ionic & Covalent Bonds
Topic: Removing the second electron
Replies: 8
Views: 182

### Re: Removing the second electron

Removing the second electron is a lot harder because of the net charge of the atom becomes more positive after removing the first electron, so removing the second electron requires more energy.
Mon Oct 22, 2018 4:24 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Test 2
Replies: 2
Views: 79

### Test 2

Do we need to know electron configurations for test 2?
Mon Oct 22, 2018 4:22 pm
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: Ionization
Replies: 1
Views: 42

### Ionization

What does ionization mean exactly?
Mon Oct 22, 2018 4:21 pm
Forum: Heisenberg Indeterminacy (Uncertainty) Equation
Topic: Test 2 and Homework Problems
Replies: 6
Views: 243

### Test 2 and Homework Problems

I've been doing the homework problems, but I don't think some of the homework problems for the Quantum World will be on the test just yet. I think all the homework problems up to 2.41 in the sixth edition can be on the test, but everything after will not (2.45-2.93). Can someone double check this?
Tue Oct 16, 2018 5:38 pm
Forum: DeBroglie Equation
Topic: Equations
Replies: 9
Views: 211

### Re: Equations

We get an equation sheet for most of the relevant equations, like we did during AP exams.
Tue Oct 16, 2018 5:37 pm
Forum: Properties of Light
Topic: Mass of Light
Replies: 5
Views: 143

### Re: Mass of Light

Light does not have a rest mass, so you can't calculate the mass of light.
Tue Oct 16, 2018 5:35 pm
Forum: Properties of Light
Topic: Threshold Energy
Replies: 4
Views: 53

### Re: Threshold Energy

The electron is still removed, but it just does not have kinetic energy.
Mon Oct 08, 2018 12:42 pm
Forum: SI Units, Unit Conversions
Topic: E23 (6th Edition)
Replies: 4
Views: 108

### Re: E23 (6th Edition)

You don't need to use avogadro's number in this problem because it says calculate in moles.
Mon Oct 08, 2018 11:46 am
Forum: SI Units, Unit Conversions
Topic: HW E.9
Replies: 3
Views: 152

### Re: HW E.9

We'll be given the formulas, so we don't need to know them by name. We just need to focus on the concepts he lectured on for the first test.
Mon Oct 08, 2018 11:44 am
Forum: SI Units, Unit Conversions
Topic: Homework for Week 2
Replies: 16
Views: 371

### Homework for Week 2

Does the homework for week 2 need to be problems about the quantum world? Can we still do problems from fundamentals for homework this week?
Sun Sep 30, 2018 10:32 pm
Forum: Empirical & Molecular Formulas
Topic: Mutiplying by a number
Replies: 3
Views: 117

### Re: Mutiplying by a number

You can multiply it by 100 to get an integer and then divide by the greatest common factor to be super exact, but just rounding it would most likely be better.
Sun Sep 30, 2018 10:26 pm
Forum: Balancing Chemical Reactions
Topic: Short cuts/methods for balancing equations
Replies: 15
Views: 236

### Re: Short cuts/methods for balancing equations

Try to take it one element at a time. Write out how many of each element there is in the reactants and do the same for the products. Then, add coefficients where necessary. It's easiest taking it step by step.
Sun Sep 30, 2018 10:21 pm
Forum: SI Units, Unit Conversions
Topic: Unit Conversions
Replies: 4
Views: 166

### Re: Unit Conversions

Remembering conversions generally just happens over time with practice through homework and classwork problems. To convert from g to kg, divide by 1000.