## Search found 29 matches

Sun Mar 13, 2016 1:21 am
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Anode/Cathode Determining
Replies: 1
Views: 303

### Re: Anode/Cathode Determining

the anode is the cell that is oxidized and the cathode is the cell that is reduced. if both reduction potentials are negative values, both are not likely to be reduced, however the larger value will be the one that is more likely to be reduced. So, if you put the values on a number line, the one tha...
Thu Mar 10, 2016 10:28 pm
Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
Topic: Winter Final 2013 #4B
Replies: 1
Views: 342

### Re: Winter Final 2013 #4B

I think I just figured it out. For anyone that had the same question, there is a 1 in the numerator because the concentration of the reactants does not count into the equation since one is in the solid state and one is water.
Thu Mar 10, 2016 10:17 pm
Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
Topic: Winter Final 2013 #4B
Replies: 1
Views: 342

### Winter Final 2013 #4B

Could you please explain where Q=1/[O2] comes from? I understand that Q is the ratio of the concentration of products and reactants, but I'm not sure how this equation is figured out.
Wed Mar 09, 2016 11:07 am
Forum: *Alcohols
Topic: How to name multiple hydroxy groups?
Replies: 1
Views: 328

### Re: How to name multiple hydroxy groups?

I believe it goes by the lowest numbering principle still if the functional groups are all just hydroxyl groups.
Mon Feb 29, 2016 12:34 am
Forum: *Alkanes
Topic: Quiz 3 Preparation
Replies: 34
Views: 11629

### Re: Quiz 3 Preparation

@Johnchou1A the Iodine gets ultimate priority since it has a higher atomic number, therefore, iodine should be 1 and bromine should be 3
Thu Feb 25, 2016 11:41 am
Forum: *Free Energy of Activation vs Activation Energy
Topic: Potential Energy vs Free Energy
Replies: 1
Views: 446

### Re: Potential Energy vs Free Energy

Free energy is the amount of energy available to do work, whereas potential energy is energy that an object has due to its position. An object tends to go from a state of higher potential energy to one of lower potential energy (this demonstrates whether a reaction is favorable or not).
Tue Feb 16, 2016 9:01 pm
Forum: General Rate Laws
Topic: Unique rate of reaction
Replies: 2
Views: 533

### Re: Unique rate of reaction

The unique rate of reaction is the rate of the reaction divided by the coefficients. So since the rate of the reaction is 6.5x10^-3, you should divide by 2 which is the coefficient of NO2.
Tue Feb 16, 2016 8:58 pm
Forum: Administrative Questions and Class Announcements
Topic: Quiz 2
Replies: 1
Views: 331

### Re: Quiz 2

No, there should not be any material on the quiz past page 75.
Tue Feb 09, 2016 10:53 am
Forum: Calculating Work of Expansion
Topic: Reversible vs irreversible expansion
Replies: 1
Views: 446

### Re: Reversible vs irreversible expansion

For reversible expansion, the external and internal pressures are initially the same. When the external pressure is changed an infinitesimally small amount, the system is allowed to do work until it reaches equilibrium. In this way (allowing the system to do work in an infinitely small amount of inc...
Mon Feb 01, 2016 11:51 am
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Positive/Negative Voltage
Replies: 1
Views: 357

### Re: Positive/Negative Voltage

You can have both negative and positive values for voltage depending on which way the reaction is going. So yes, both negative and positive values are acceptable.
Wed Jan 27, 2016 11:49 am
Forum: Concepts & Calculations Using Second Law of Thermodynamics
Topic: Describing changes in entropy
Replies: 2
Views: 341

### Re: Describing changes in entropy

Generally, entropy is just described as increasing or decreasing. This change in entropy is then useful in understanding and analyzing reactions.
Wed Jan 27, 2016 11:43 am
Forum: Administrative Questions and Class Announcements
Topic: Workbook Quizes
Replies: 2
Views: 470

### Re: Workbook Quizes

The workbook has practice quizzes with answers from previous years as a study resource. There is also a quiz in the workbook which you can complete and turn in to your discussion section on the day of the quiz. These quizzes will be graded, and will replace your lowest quiz score, so it is highly re...
Wed Jan 20, 2016 11:35 am
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Using bond enthalpies to find reaction enthalpy
Replies: 1
Views: 558

### Re: Using bond enthalpies to find reaction enthalpy

The Carbon atoms in the C2H2 molecule are bonded together by a triple bond, so this must be broken and they must be rearranged into a ring in which the Carbons are bonded by only single bonds. It takes more energy to break a triple bond than a single bond, so this might be the reason behind the disc...
Wed Jan 13, 2016 11:35 am
Forum: Thermodynamic Systems (Open, Closed, Isolated)
Topic: reversible and irreversible process
Replies: 3
Views: 463

### reversible and irreversible process

Can you explain what the difference in reversible and irreversible processes and what the significance of both are?
Thank you!
Mon Jan 11, 2016 11:15 am
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Reg Calorimeter v. Bomb Calorimeter
Replies: 3
Views: 3945

### Re: Reg Calorimeter v. Bomb Calorimeter

Both calorimeters, the bomb calorimeter and the coffee cup calorimeter, serve the same purpose and work in the same way. Both measure changes of heat that occur as a result of a reaction inside. The bomb calorimeter is just more advanced in that it is capable of withstanding more pressure from a rea...
Fri Jan 08, 2016 11:12 am
Forum: Calculating Work of Expansion
Topic: Thermodynamic definition of reversible/irreversible process
Replies: 1
Views: 278

### Re: Thermodynamic definition of reversible/irreversible proc

The way I interpreted it was that a reversible process is essentially a "balance" in a way. This means that any off-setting measurements, however infinitely small, can push it in either direction.
Tue Dec 01, 2015 11:17 am
Forum: Amphoteric Compounds
Topic: Autoprotolysis
Replies: 2
Views: 708

### Re: Autoprotolysis

Autoprolysis occurs when a molecule donates a proton to a molecule of the same type. If a molecule donates a proton to a molecule of a different type, then it is just an example of an acid-base reaction. Autoprolysis is just specifically a proton transfer between like-molecules. An example is water....
Sun Nov 22, 2015 10:09 pm
Forum: Trends in The Periodic Table
Topic: Video: Periodic Trends-Electronegativity/Ionization Energy
Replies: 2
Views: 635

### Video: Periodic Trends-Electronegativity/Ionization Energy

Shelby Yee discussion 1J
Stephanie Manzo discussion 1H
Wed Nov 18, 2015 10:57 am
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Partial Pressures and Equilibrium
Replies: 2
Views: 464

### Re: Partial Pressures and Equilibrium

You set up the K constant equation, Kp=[products]/[reactants]. When you plug in known values you should be able to solve for the missing partial pressure.
Tue Nov 10, 2015 6:59 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Equilibrium constant and p
Replies: 5
Views: 478

### Re: Equilibrium constant and p

When Dr. Lavelle did examples in class I do not believe that he put the "P" in. So maybe that indicates that it's not necessary on tests and quizzes.
Mon Oct 26, 2015 12:53 pm
Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
Replies: 1
Views: 254

Radicals are atoms, molecules, or ions with an unpaired electron. Biradicals are atoms, molecules, or ions with 2 unpaired electrons. This is significant in that it makes them extremely reactive.
Wed Oct 21, 2015 2:46 pm
Forum: Heisenberg Indeterminacy (Uncertainty) Equation
Topic: Using the Equation for Subatomic Particles
Replies: 1
Views: 482

### Re: Using the Equation for Subatomic Particles

Actually, the Heisenberg equation demonstrates the opposite. Your supposition that a particle with a larger mass will have a greater certainty of position than a smaller particle traveling at the same velocity is correct. The Heisenberg equation calculates a value of uncertainty, so when dividing h/...
Mon Oct 12, 2015 12:29 pm
Forum: Photoelectric Effect
Topic: Intensity with photoelectric effect
Replies: 1
Views: 443

### Re: Intensity with photoelectric effect

If light exhibited only wave-like properties, then increasing the amplitude of the light waves should have caused electrons to be ejected. Scientists conducting the experiment tried using a brighter light source, but did not achieve the expected result. Instead, when using a light source that emitte...
Wed Oct 07, 2015 4:54 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Electron Configurations in the d Orbital
Replies: 2
Views: 464

### Re: Electron Configurations in the d Orbital

The 4s subshell usually fills up before the 3d subshell. The exceptions occur when the d subshell is half full (d^5) or full (d^10). This happens because the 3d subshell is most stable when each orbital is balanced (has the same number of electrons in each orbital), so to do this it will "steal...
Sat Oct 03, 2015 1:07 am
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: Balmer Series
Replies: 1
Views: 450

### Re: Balmer Series

The energy of the photon emitted is equal to the amount of energy absorbed by the electron to reach the higher energy level. It is not a common practice to determine the energy between electron energy levels by studying absorption because it is a more difficult experiment and could be harder to yiel...
Sat Oct 03, 2015 12:51 am
Forum: Properties of Electrons
Topic: Atomic Spectra Explanation
Replies: 1
Views: 374

### Re: Atomic Spectra Explanation

Spectral lines on the emission spectrum show the specific wavelengths of light that are absorbed or emitted from an electron in a transitory state between energy levels. So, you could use the different wavelengths to find the amount of energy given off or absorbed to attain different energy levels u...
Sat Oct 03, 2015 12:35 am
Forum: Photoelectric Effect
Topic: Calculating Light Absorption
Replies: 1
Views: 315

### Re: Calculating Light Absorption

The energy of the light emitted as a photon is equal to the amount of light absorbed by the electron. By calculating the light energy emitted using the Rydberg formula, you are also calculating the amount of light energy that was initially absorbed.
Sat Oct 03, 2015 12:27 am
Forum: Heisenberg Indeterminacy (Uncertainty) Equation
Topic: h/4pi in Heisenberg's Indeterminacy Equation
Replies: 3
Views: 2324

### Re: h/4pi in Heisenberg's Indeterminacy Equation

h/4pi is an experimentally determined constant. Basically, it exists to show that there is a limit to the certainty to which you can know the position and the momentum of the particle simultaneously.
Fri Oct 02, 2015 1:29 pm
Forum: Heisenberg Indeterminacy (Uncertainty) Equation
Topic: Psi in the Born interpretation of the wave function
Replies: 1
Views: 406

### Psi in the Born interpretation of the wave function

Hello, Can someone please explain what psi represents in the Born interpretation of the wave function? I understand that psi^2 is the probability density, and when graphed can actually show the likelihood that the particle will be found in a specific region. But what is the significance of just psi ...