Search found 50 matches
- Sun Mar 15, 2020 6:48 am
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: Flipping the anode
- Replies: 4
- Views: 380
Flipping the anode
why do we flip anode in cell notation?
- Sun Mar 15, 2020 6:46 am
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: Same charge
- Replies: 1
- Views: 255
Same charge
Sometimes when I write half reactions both species have the same charge? What do I do, how do I know how many electrons have been transferred?
- Sun Mar 15, 2020 6:45 am
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: insoluble
- Replies: 1
- Views: 273
insoluble
If the reactant is insoluble, then why would E cell be negative?
- Sun Mar 15, 2020 6:45 am
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: electrodes
- Replies: 3
- Views: 349
electrodes
What does it mean by standard potential of an electrode is the standard potential of the cell in which electrodes lies on the right and hydrogen electrodes lies on the left?
- Sun Mar 15, 2020 6:44 am
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: 6M 2
- Replies: 2
- Views: 288
6M 2
For the equation deltaG= -nFE, why can’t you add up the E’s of both half reaction to get Ecell?
- Sun Mar 15, 2020 6:44 am
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: nernst
- Replies: 5
- Views: 451
nernst
When you double the equation why does the G increase the E stay the same?
- Mon Mar 02, 2020 5:20 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: 6L5 b.
- Replies: 3
- Views: 310
Re: 6L5 b.
You need to use platinum as a metal electrode for both sides since none of the products or reactants are conducting metal solids. I2 is a solid at the anode, but since it is a metal it doesn't count. At the cathode, there are only aqueous ions so you would also need the platinum electrode here to a...
- Mon Mar 02, 2020 5:15 pm
- Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
- Topic: 6M.11
- Replies: 3
- Views: 387
6M.11
Why do we flip the reducing agent in the cell notation for this question?
- Mon Mar 02, 2020 2:21 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: 6L5 b.
- Replies: 3
- Views: 310
6L5 b.
Why do we use platinum on both sides in this case? Because one side already has a solid product?
- Thu Feb 20, 2020 1:18 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Thermodynamics Outline Second Page [ENDORSED]
- Replies: 2
- Views: 432
Thermodynamics Outline Second Page [ENDORSED]
For the first bullet point on the second page of the outline, what is the explanation for "why reaction free energy depends on pressure and the equilibrium constant?"
- Mon Jan 27, 2020 3:16 pm
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: Expansion of a system
- Replies: 8
- Views: 1198
Re: Expansion of a system
Is compression also a form of work?
- Mon Jan 27, 2020 3:14 pm
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: 4A 1 Part c)
- Replies: 5
- Views: 358
Re: 4A 1 Part c)
Does the pressure change in a bomb calorimeter?
- Mon Jan 27, 2020 3:10 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Delta U
- Replies: 3
- Views: 341
Re: Delta U
Delta U is the change in internal energy described by the first law of thermodynamics. The equation for delta u is heat (q) + work (w) = Internal energy ( delta U).
- Mon Jan 27, 2020 3:06 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Constant Pressure and how you get it in a calorimeter
- Replies: 3
- Views: 226
Re: Constant Pressure and how you get it in a calorimeter
I am still confused about the differences in pressure between the bomb calorimeter and coffee cup calorimeter. Why does the pressure change in a bomb calorimeter if its sealed?
- Mon Jan 27, 2020 3:00 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Heat Capacity
- Replies: 7
- Views: 401
Re: Heat Capacity
The book states that "The constant-volume and constant-pressure heat capacities of a solid substance are similar; the same is true of a liquid but not of a gas". Why is this not true for a gas? I'm curious about this as well because in lecture he said you need to specify these different h...
- Mon Jan 27, 2020 2:58 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: bomb calorimeter
- Replies: 8
- Views: 1230
Re: bomb calorimeter
Could this be considered an isolated system because it is insulated?
- Mon Jan 27, 2020 2:55 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Irreversible Expansion
- Replies: 4
- Views: 271
Re: Irreversible Expansion
I'm still confused about the difference between reversible and irreversible equilibrium. The book gives an example of a piston. Can someone please explain it in the context of that?
- Mon Jan 27, 2020 2:45 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: work
- Replies: 5
- Views: 322
Re: work
Work is w=-P (pressure) (change in volume) . If the volume is increasing or decreasing change the sign accordingly. Also to convert J times atm to J multiply the value by 101.325 J/ L times atm.
- Mon Jan 27, 2020 2:34 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Homework Question 4A.3
- Replies: 2
- Views: 228
Re: Homework Question 4A.3
The 7th editon solution manual says 28J.
- Mon Jan 27, 2020 2:30 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Advice from a Medical Student [ENDORSED]
- Replies: 297
- Views: 425371
Re: Advice from a Medical Student [ENDORSED]
Thank you so much for your words of wisdom!
- Fri Jun 08, 2018 9:53 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 3665373
Re: Post All Chemistry Jokes Here
If avogadro calls tell him to leave his number...
- Fri Jun 08, 2018 9:52 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 3665373
Re: Post All Chemistry Jokes Here
Do I know any jokes about sodium? Na
- Fri Jun 08, 2018 9:51 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 3665373
Re: Post All Chemistry Jokes Here
A covalent bond joke? Thanks for sharing...
- Fri Jun 08, 2018 9:50 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 3665373
Re: Post All Chemistry Jokes Here
Don't tell jokes to noble gases you'll get no reaction.
- Fri Jun 08, 2018 9:50 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 3665373
Re: Post All Chemistry Jokes Here
I tell bad chemistry jokes bc all the good ones Argon...
- Fri Jun 08, 2018 9:49 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 3665373
Re: Post All Chemistry Jokes Here
I like chemistry jokes bc they are funny
He He He
He He He
- Fri Jun 08, 2018 9:48 pm
- Forum: Resonance Structures
- Topic: Contributing to Resonance Structures
- Replies: 4
- Views: 643
Re: Contributing to Resonance Structures
The molecule with the lowest formal charge is deemed as most stable and that would be the most favorable resonance structure.
- Fri Jun 08, 2018 9:28 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: formal charge and VSEPR
- Replies: 8
- Views: 1063
Re: formal charge and VSEPR
VESPR is used to predict molecular geometry using valence shell electrons
- Fri Jun 08, 2018 9:13 pm
- Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
- Topic: Isoelectronic
- Replies: 14
- Views: 2171
Re: Isoelectronic
Isoelectronic means that both atoms have the same number of valence electrons. Ex: Na+,F-
- Fri Jun 08, 2018 9:12 pm
- Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
- Topic: Isoelectronic
- Replies: 14
- Views: 2171
Re: Isoelectronic
Isoelectronic means that both atoms have the same number of valence electrons. Ex: Na+,F-
- Fri Jun 08, 2018 8:54 pm
- Forum: Hybridization
- Topic: Pi bonds in triple bond
- Replies: 17
- Views: 1894
Re: Pi bonds in triple bond
one sigma bond and 2 pi bonds
- Wed Jun 06, 2018 4:41 pm
- Forum: Properties of Light
- Topic: Wave and Particle
- Replies: 10
- Views: 1250
Re: Wave and Particle
a single particle of light is called a photon whereas a stream of photons is light
- Wed Jun 06, 2018 4:39 pm
- Forum: Bond Lengths & Energies
- Topic: unit box
- Replies: 3
- Views: 633
unit box
What is a unit box?
- Wed Jun 06, 2018 4:36 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Le Chatelier's
- Replies: 1
- Views: 407
Le Chatelier's
What is the relationship between Le Chatelier's principle and hydrogen molecules?
- Wed Jun 06, 2018 4:34 pm
- Forum: Polyprotic Acids & Bases
- Topic: oxacids and carboxylic acids
- Replies: 5
- Views: 1199
oxacids and carboxylic acids
What is the difference between oxoacids and carboxylic acids?
- Wed Jun 06, 2018 4:32 pm
- Forum: Conjugate Acids & Bases
- Topic: conjugate seesaw
- Replies: 1
- Views: 341
conjugate seesaw
What is meant by conjugate see saw?
- Wed Jun 06, 2018 4:26 pm
- Forum: Conjugate Acids & Bases
- Topic: pKa [ENDORSED]
- Replies: 3
- Views: 618
pKa [ENDORSED]
How do you know the pKa?
- Wed Jun 06, 2018 4:25 pm
- Forum: Identifying Acidic & Basic Salts
- Topic: Identifying strong acids and bases
- Replies: 2
- Views: 609
Re: Identifying strong acids and bases
What's a binary acid?
- Wed Jun 06, 2018 4:19 pm
- Forum: Limiting Reactant Calculations
- Topic: Reactant vs. Reagent [ENDORSED]
- Replies: 23
- Views: 34796
Re: Reactant vs. Reagent [ENDORSED]
They can be used interchangeably, but reagents are not usually solvents
- Thu May 17, 2018 9:32 pm
- Forum: Ionic & Covalent Bonds
- Topic: Configurations
- Replies: 4
- Views: 561
Configurations
Why do you remove electrons from the highest energy levels first? Ex: from 5s^2 before 4d^10
- Sun Apr 29, 2018 9:40 pm
- Forum: Photoelectric Effect
- Topic: increasing frequency/ light intensity
- Replies: 5
- Views: 1354
Re: increasing frequency/ light intensity
Changing the frequency changes the wavelength and changing the number of photons changes the light intensity.
- Sun Apr 29, 2018 9:38 pm
- Forum: Trends in The Periodic Table
- Topic: Radius
- Replies: 6
- Views: 792
Re: Radius
In a neutral atom the atomic and ionic radii are the same but if there are cations and anions the electron loses a shell and the ionic radius becomes smaller.
- Sun Apr 29, 2018 7:00 pm
- Forum: Properties of Light
- Topic: Homework Problem(s) [ENDORSED]
- Replies: 6
- Views: 655
Re: Homework Problem(s) [ENDORSED]
The masses of these will be given on equation sheet.
- Sun Apr 29, 2018 6:52 pm
- Forum: Quantum Numbers and The H-Atom
- Topic: What do l and m represent? [ENDORSED]
- Replies: 6
- Views: 1094
Re: What do l and m represent? [ENDORSED]
M represents magnetic momentum and l represents angular momentum
- Sun Apr 29, 2018 6:46 pm
- Forum: Quantum Numbers and The H-Atom
- Topic: Amount of Electrons [ENDORSED]
- Replies: 6
- Views: 1081
Re: Amount of Electrons [ENDORSED]
These numbers respond to a single electron. Think of it like an ID number each electron has its unique set of quantum numbers.
- Sun Apr 29, 2018 6:32 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: Why does 4s fill up before 3d?
- Replies: 4
- Views: 483
Why does 4s fill up before 3d?
Why does the 4s orbital fill up before 3d orbital other than that it's at a "lower energy level"?
- Sun Apr 29, 2018 6:27 pm
- Forum: DeBroglie Equation
- Topic: Quanta
- Replies: 5
- Views: 728
Re: Quanta
Quanta is a small packet of energy such as a photon.
- Sun Apr 29, 2018 6:23 pm
- Forum: DeBroglie Equation
- Topic: Calculating wavelength of an electron
- Replies: 4
- Views: 615
Re: Calculating wavelength of an electron
When you know velocity of an electron and need to know wavelength use De Broglie's equation. lambda= h/mv
- Sun Apr 29, 2018 6:19 pm
- Forum: *Black Body Radiation
- Topic: What is Significant about Black Body Radiation? [ENDORSED]
- Replies: 4
- Views: 1124
Re: What is Significant about Black Body Radiation? [ENDORSED]
Black bodies are hot objects that glow(incandescence) and as the temperature rises and shorter wavelengths. The ultraviolet catastrophe is when energy is transferred in packets(quanta), otherwise there would always be darkness.
- Mon Apr 16, 2018 11:54 am
- Forum: Empirical & Molecular Formulas
- Topic: Molecular to Empirical [ENDORSED]
- Replies: 12
- Views: 1948
Re: Molecular to Empirical [ENDORSED]
To go from the molecular formula to the empirical formula you should divide by the greatest common denominator. Please keep in mind that the molecular and empirical formula can be the same.