Search found 96 matches
- Wed Mar 11, 2020 6:04 pm
- Forum: Administrative Questions and Class Announcements
- Topic: final
- Replies: 14
- Views: 923
Re: final
I agree I think we just have to wait for more information, but I assume it will still be 3 hours.
- Tue Mar 10, 2020 8:05 pm
- Forum: Second Order Reactions
- Topic: 7B.13 Numerator
- Replies: 2
- Views: 249
7B.13 Numerator
For this problem, when it asks for one sixteenth or one fourth, we change the numerator (e.g. to 16/[A]o).
What's the math behind this?
What's the math behind this?
- Sun Mar 01, 2020 11:57 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: Corrosion
- Replies: 5
- Views: 392
Re: Corrosion
I think we need to know about rust for the corrosion section
- Sun Mar 01, 2020 11:56 pm
- Forum: Balancing Redox Reactions
- Topic: Determining direction of flow
- Replies: 15
- Views: 773
Re: Determining direction of flow
The cell diagram always has the anode on the left and the cathode to the right to demonstrate this, so the electrons would move from the anode to the cathode
- Sun Mar 01, 2020 11:55 pm
- Forum: Interesting Applications: Rechargeable Batteries (Cell Phones, Notebooks, Cars), Fuel Cells (Space Shuttle), Photovoltaic Cells (Solar Panels), Electrolysis, Rust
- Topic: rust
- Replies: 9
- Views: 715
Re: rust
I think we just need to know the half reaction for rust.
- Sun Mar 01, 2020 11:54 pm
- Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
- Topic: n value
- Replies: 9
- Views: 568
Re: n value
Both the oxidation and reduction half reaction would have the same number of electrons transferred between them, so this would be your n.
- Sun Mar 01, 2020 11:53 pm
- Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
- Topic: n in Equation
- Replies: 6
- Views: 441
Re: n in Equation
Look for the number of electrons being transferred between the half reactions
- Sun Mar 01, 2020 11:53 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: anodes and cathodes
- Replies: 1
- Views: 134
Re: anodes and cathodes
cathode is where reduction occurs and the anode is where oxidation occurs
In a cell diagram, the anode is on the left side while the cathode is on the right.
In a cell diagram, the anode is on the left side while the cathode is on the right.
- Wed Feb 26, 2020 1:42 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: 6M.5
- Replies: 1
- Views: 188
6M.5
For each reaction that is spontaneous under standard conditions (that is, K . 1), write a cell diagram, determine the standard cell potential, and calculate deltaG for the reaction: (a) 2NO32(aq)18H1(aq)16Hg(l)S ~~For the cell diagram, why would the right side only be balanced with Platinum vs the l...
- Sun Feb 23, 2020 6:11 pm
- Forum: Entropy Changes Due to Changes in Volume and Temperature
- Topic: Boltzmann Formula
- Replies: 11
- Views: 869
Re: Boltzmann Formula
w refers to the number of possible states/possible orientations
- Sun Feb 23, 2020 6:10 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Spontaneous
- Replies: 23
- Views: 1169
Re: Spontaneous
Gibbs Free Energy being at zero signals that the reaction is at equilibrium
- Sun Feb 23, 2020 6:09 pm
- Forum: Van't Hoff Equation
- Topic: Significance of Van't Hoff Equation
- Replies: 8
- Views: 573
Re: Significance of Van't Hoff Equation
My TA said that something like this equation was just a way of mathematically showing that heating an endothermic reaction favors products vs heating an exothermic favors reactants
- Sun Feb 23, 2020 6:08 pm
- Forum: Balancing Redox Reactions
- Topic: Flow of electrons
- Replies: 11
- Views: 760
Re: Flow of electrons
Electrons flow from the anode to cathode usually so I don't think there's an exception
- Sun Feb 23, 2020 6:06 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: neg vs pos
- Replies: 9
- Views: 676
Re: neg vs pos
Positive voltage = spontaneous reaction
Negative voltage = nonspontaneous reaction
Negative voltage = nonspontaneous reaction
- Sun Feb 23, 2020 6:05 pm
- Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
- Topic: Anode & cathode
- Replies: 5
- Views: 345
Re: Anode & cathode
My TA mentioned how oxidation is related to the anode because both started with vowels while the cathode is with reduction because both started with consonants.
- Sun Feb 23, 2020 6:04 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: chemistry community posts
- Replies: 12
- Views: 606
Re: chemistry community posts
5 posts constitute one week
- Sun Feb 23, 2020 6:03 pm
- Forum: Van't Hoff Equation
- Topic: Significance of Van't Hoff Equation
- Replies: 8
- Views: 573
Re: Significance of Van't Hoff Equation
Van't Hoff allows us to find K at different temperatures from Gibb's since K changes when the temperature does
- Sun Feb 23, 2020 5:58 pm
- Forum: Balancing Redox Reactions
- Topic: Identifying Half Reactions
- Replies: 4
- Views: 331
Re: Identifying Half Reactions
Gaining electrons is reduction (going for negative) and losing electrons is oxidation (going for positive)
- Mon Feb 17, 2020 5:37 pm
- Forum: Calculating Standard Reaction Entropies (e.g. , Using Standard Molar Entropies)
- Topic: Is spontaneity determined by entropy or free energy?
- Replies: 9
- Views: 1905
Re: Is spontaneity determined by entropy or free energy?
Spotaneity is determined by both as presented in the chart above, but either could be used in order to see whether a reaction is spontaneous or not
- Mon Feb 17, 2020 5:35 pm
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: Constant R
- Replies: 15
- Views: 1028
Re: Constant R
You can find the units used on the equation sheet
Just look for what units the problem gives you and what you are trying to get. Using R with the right units allows you to cancel out the things you don't need in order to get what you want
Just look for what units the problem gives you and what you are trying to get. Using R with the right units allows you to cancel out the things you don't need in order to get what you want
- Mon Feb 17, 2020 5:33 pm
- Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
- Topic: Reversible vs Irreversible
- Replies: 7
- Views: 436
Re: Reversible vs Irreversible
It's also important to note that reversible does the most amount of work.
- Mon Feb 17, 2020 5:32 pm
- Forum: Calculating Work of Expansion
- Topic: Work Equation
- Replies: 6
- Views: 589
Re: Work Equation
Irreversible uses w=-Pex * deltaV
Reversible uses w=-nRTln(V2/V1) (Does the most work)
Usually the problem will be explicit in whether a reaction is reversible or irreversible
Reversible uses w=-nRTln(V2/V1) (Does the most work)
Usually the problem will be explicit in whether a reaction is reversible or irreversible
- Mon Feb 17, 2020 5:27 pm
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: isothermal reactions
- Replies: 8
- Views: 588
Re: isothermal reactions
For isothermal, there is no change in temperature therefore there is no change in internal energy
- Mon Feb 17, 2020 5:25 pm
- Forum: Entropy Changes Due to Changes in Volume and Temperature
- Topic: Cv vs Cp
- Replies: 17
- Views: 939
Re: Cv vs Cp
Cv is constant volume and Cp is constant pressure
- Mon Feb 17, 2020 5:24 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Midterm Curve
- Replies: 45
- Views: 2165
Re: Midterm Curve
I don't think the midterm itself is curved
- Sun Feb 09, 2020 11:45 pm
- Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
- Topic: DeltaH
- Replies: 2
- Views: 122
Re: DeltaH
Delta H stands for Change in Enthalpy
H - Enthalpy
Delta - Change in
H - Enthalpy
Delta - Change in
- Sun Feb 09, 2020 11:43 pm
- Forum: Ideal Gases
- Topic: Gas constant
- Replies: 10
- Views: 514
Re: Gas constant
Choosing which R to use depends on what units you are trying to cancel out in order to solve for your specific answer.
- Sun Feb 09, 2020 9:02 pm
- Forum: Concepts & Calculations Using Second Law of Thermodynamics
- Topic: Constant T,P,V
- Replies: 4
- Views: 171
Re: Constant T,P,V
Most of these variables will be given in the question in order to solve.
There was also a list put up with some useful terms that describe whether some things are constant, like "isothermal" for constant temperature or "isochoric" for constant volume.
There was also a list put up with some useful terms that describe whether some things are constant, like "isothermal" for constant temperature or "isochoric" for constant volume.
- Sun Feb 09, 2020 9:00 pm
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: First Law of Themordynamics
- Replies: 4
- Views: 232
Re: First Law of Themordynamics
I think for all intents and purposes they represent the same idea.
- Sun Feb 09, 2020 8:59 pm
- Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
- Topic: Useful Summary of Thermodynamic Definitions
- Replies: 55
- Views: 18397
Re: Useful Summary of Thermodynamic Definitions
Thank you!
I think we will need to know these terms for the test in order to interpret problems
I think we will need to know these terms for the test in order to interpret problems
- Sun Feb 09, 2020 8:57 pm
- Forum: Concepts & Calculations Using Second Law of Thermodynamics
- Topic: Difference between Cv and Cp?
- Replies: 8
- Views: 506
Difference between Cv and Cp?
Do they represent the same value or no?
I looked some stuff up and what I've seen has varied
I looked some stuff up and what I've seen has varied
- Wed Jan 29, 2020 5:36 pm
- Forum: Calculating Work of Expansion
- Topic: Converting gas volume to mols
- Replies: 2
- Views: 87
Converting gas volume to mols
When you convert a gas to mols, they said you turn it from Liters to Mols through the conversion factor of:
1mol/22.4
but I'm not entirely certain if this is accurate or not
1mol/22.4
but I'm not entirely certain if this is accurate or not
- Fri Jan 24, 2020 9:47 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: pKa and pKb
- Replies: 17
- Views: 873
Re: pKa and pKb
pKa + pKa = Kw (autoprotolysis constant) = 14
This equation can be flipped around respectively to find a value you need.
This equation can be flipped around respectively to find a value you need.
- Fri Jan 24, 2020 9:45 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Le Chatelier's Principle
- Replies: 19
- Views: 1651
Re: Le Chatelier's Principle
Le Chatelier's Principle applies whenever a system is "disturbed" in the sense that reactants or products are added/removed.
- Fri Jan 24, 2020 9:44 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Temperature
- Replies: 6
- Views: 205
Re: Temperature
Increasing and decreasing temperature changes the value of K because it acts as either a product or reactant (exothermic or endothermic respectively)
- Fri Jan 24, 2020 9:43 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: exothermic reactions
- Replies: 19
- Views: 1937
Re: exothermic reactions
Adding heat to an exothermic reaction favors reactants because heat is a product, so thereby increasing the product, it favors the formation of reactants
- Fri Jan 24, 2020 9:41 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: definition of a buffer
- Replies: 8
- Views: 403
Re: definition of a buffer
A buffer solution is an aqueous solution consisting of a mixture of a weak acid and its conjugate base, or vice versa. Its pH changes very little when a small amount of strong acid or base is added to it.
- Fri Jan 24, 2020 9:39 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: solvent
- Replies: 10
- Views: 388
Re: solvent
Only include (aq) and (g) in your equilibrium, as solids and liquids/solvents like H2O are not.
- Fri Jan 24, 2020 9:36 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: suggestions
- Replies: 16
- Views: 547
Re: suggestions
I always use Khan academy
- Fri Jan 24, 2020 9:35 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Q and K
- Replies: 4
- Views: 157
Re: Q and K
K the point of equilibrium while Q is a reaction quotient by which the reaction is not at equilibrium yet
The value of Q relative to K can give you clues towards which way the reaction is going
The value of Q relative to K can give you clues towards which way the reaction is going
- Fri Jan 24, 2020 9:33 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: k<10^-3
- Replies: 9
- Views: 340
Re: k<10^-3
I think it's just a given concept but not necessarily set in stone for identification purposes
- Fri Jan 24, 2020 9:32 pm
- Forum: Ideal Gases
- Topic: Kc vs Kp
- Replies: 109
- Views: 4414
Re: Kc vs Kp
You use Kp unless it specifically asks for Kc
- Sun Jan 12, 2020 4:53 pm
- Forum: Ideal Gases
- Topic: Kc and Kp
- Replies: 8
- Views: 260
Re: Kc and Kp
I believe Kc deals with Equilibrium Constant concentrations while Kp deals with Equilibrium Constant partial pressures
- Sun Jan 12, 2020 4:51 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Kc vs Kp
- Replies: 10
- Views: 256
Re: Kc vs Kp
Tanmay Singhal 1H wrote:I'm confused on why water isn't counted in the K/Q equation.
Water is not counted because water is a liquid
Solids and liquids are not included in the equilibrium constant expressions (K=P/R)
- Sun Jan 12, 2020 4:50 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: Situations in which Q=K
- Replies: 7
- Views: 337
Re: Situations in which Q=K
When Q=K, then the reaction is at equilibrium
- Sun Jan 12, 2020 4:49 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Different types of K
- Replies: 9
- Views: 262
Re: Different types of K
K = Kc = Kp
They are just different notations for whatever phase your equation is dealing with (e.g. gas w/ pressure)
Similarly, K = Q = Qc = Qp
They are just different notations for whatever phase your equation is dealing with (e.g. gas w/ pressure)
Similarly, K = Q = Qc = Qp
- Sun Jan 12, 2020 4:47 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: Equilibrium vs. Non-Equilibrium
- Replies: 4
- Views: 150
Re: Equilibrium vs. Non-Equilibrium
If Q does not equal K or vice versa, then I believe you would have to solve for either respectively. If Q is the same value calculated, then the reaction is at equilibrium
- Sun Jan 12, 2020 4:45 pm
- Forum: Ideal Gases
- Topic: Conditions for Ideal Gases
- Replies: 5
- Views: 565
Re: Conditions for Ideal Gases
The ideal gas law assumes that conditions of measurement are perfect, but in the experimental sense, they aren't.
- Sun Jan 12, 2020 4:43 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Finding K: liquids and aqueous
- Replies: 7
- Views: 229
Re: Finding K: liquids and aqueous
While liquids do not have a defined concentration (molarity), aqueous solutions do.
- Sun Jan 12, 2020 4:40 pm
- Forum: Ideal Gases
- Topic: Bars vs atmospheres
- Replies: 13
- Views: 327
Re: Bars vs atmospheres
Both work as their respective units of measurement, mostly dealing with gasses and pressure
- Sun Jan 12, 2020 4:38 pm
- Forum: Ideal Gases
- Topic: R in PV=nRT
- Replies: 34
- Views: 5953
Re: R in PV=nRT
R is the gas constant, should be found on the equations sheet
- Sun Nov 17, 2019 6:02 pm
- Forum: Ionic & Covalent Bonds
- Topic: Character of Bonds
- Replies: 7
- Views: 487
Re: Character of Bonds
Maddie wrote:Will he give us the actual electronegativity values on the tests though?
We won't be getting electronegativity values, so we have to know the trend on the periodic table.
- Sun Nov 17, 2019 6:01 pm
- Forum: Ionic & Covalent Bonds
- Topic: London Dispersion
- Replies: 13
- Views: 653
Re: London Dispersion
Anokhi Patel 4G wrote:what exactly is london dispersion?
London dispersion is another name for Van der Waals forces, which is essentially really weak and temporary polarizations occurring due to the random movement of electrons in a molecule. It is the weakest intermolecular force and may occur on all molecules.
- Sun Nov 17, 2019 5:59 pm
- Forum: Lewis Structures
- Topic: Carbon Monoxide
- Replies: 4
- Views: 329
Re: Carbon Monoxide
Having a triple bond in CO fulfills the octet rule for Carbon has Carbon would want to have an octet.
Satisfying the octet rule precedes Formal charges
Satisfying the octet rule precedes Formal charges
- Sun Nov 17, 2019 5:56 pm
- Forum: Bond Lengths & Energies
- Topic: Strongest Bonds
- Replies: 11
- Views: 884
Re: Strongest Bonds
Intermolecular strengths are: Ion-dipole, H-bond, Dipole-Dipole, Ion-induced dipole, Dipole-induced dipole, and London Forces
- Sun Nov 17, 2019 5:54 pm
- Forum: Octet Exceptions
- Topic: Octet expansion
- Replies: 6
- Views: 532
Re: Octet expansion
Elements after the 3rd period may have expanded octets due to their access to the 3d subshell.
- Sun Nov 17, 2019 5:52 pm
- Forum: Formal Charge and Oxidation Numbers
- Topic: Calculating formal charge
- Replies: 8
- Views: 629
Re: Calculating formal charge
Doesn't matter where you start as long as the overall FC of the molecule matches what is given or is at the most favorable FC which is 0.
- Sat Nov 09, 2019 10:17 pm
- Forum: Formal Charge and Oxidation Numbers
- Topic: Formal Charge
- Replies: 9
- Views: 336
Re: Formal Charge
You try to make the formal charge 0 where possible as long as the octet rule is satisfied. If not, you aim for the lowest energy structure possible that satisfies the octet rule, which involves having the lowest number of formal charges, especially with the central atom.
- Sat Nov 09, 2019 10:16 pm
- Forum: Octet Exceptions
- Topic: octet exceptions
- Replies: 11
- Views: 566
Re: octet exceptions
Usually any element under the 3rd period may have an expanded octet due to having the whole of the d-block possible in their electron configuration
- Sat Nov 09, 2019 10:14 pm
- Forum: Resonance Structures
- Topic: Resonance Structures
- Replies: 18
- Views: 1059
Re: Resonance Structures
Resonance structures essentially combine into a resonance hybrid. Each resonance structure describes how possible delocalized electrons may form bonds.
- Sat Nov 09, 2019 10:11 pm
- Forum: Lewis Structures
- Topic: Drawing Lewis Structures
- Replies: 18
- Views: 639
Re: Drawing Lewis Structures
When you draw Lewis structures, you just try to get the lowest energy structure possible, typically with a 0 formal charge where possible. If not, I think you just make the entire charge of the atom match what is given.
- Sat Nov 09, 2019 10:09 pm
- Forum: Ionic & Covalent Bonds
- Topic: C, N, O, and F
- Replies: 13
- Views: 609
Re: C, N, O, and F
These four elements C, N, O, F follow the Octet guideline as they do not have access to the expanded octets found with the d block
- Sun Nov 03, 2019 11:23 pm
- Forum: DeBroglie Equation
- Topic: When to use the DeBroglie equation?
- Replies: 6
- Views: 353
Re: When to use the DeBroglie equation?
I think you use De Broglie's for any time you are given any values toward the variables for conversions between them.
- Sun Nov 03, 2019 11:21 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Order of removing electrons
- Replies: 4
- Views: 244
Re: Order of removing electrons
Once 4s is filled, it has a higher energy than the 3d orbital, so the electrons removed are from 4s, the outermost shell.
- Sun Nov 03, 2019 11:20 pm
- Forum: Trends in The Periodic Table
- Topic: Midterm Question Regarding Metals, Nonmetals, etc
- Replies: 2
- Views: 79
Re: Midterm Question Regarding Metals, Nonmetals, etc
I think we just need to know how the concept relates to whatever question is being asked as opposed to actually naming them.
- Sun Nov 03, 2019 11:17 pm
- Forum: Trends in The Periodic Table
- Topic: Does H have the highest ionization energy?
- Replies: 4
- Views: 149
Re: Does H have the highest ionization energy?
Flourine has the highest ionization energy, as it requires the most energy in order to lose an electron.
I believe Noble gases are excluded in this case but I'm not too sure.
I believe Noble gases are excluded in this case but I'm not too sure.
- Sun Nov 03, 2019 11:14 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: Degenerate orbitals
- Replies: 4
- Views: 262
Re: Degenerate orbitals
"Degenerate" is just a term used to describe the spdf orbitals having the same energy; This applies to a single-electron atom like Hydrogen.
I'm not sure if this was mentioned in lecture but I know for sure that it was mentioned at a review session
I'm not sure if this was mentioned in lecture but I know for sure that it was mentioned at a review session
- Sun Nov 03, 2019 11:11 pm
- Forum: Properties of Electrons
- Topic: Photoelectric effect
- Replies: 5
- Views: 447
Re: Photoelectric effect
Khan Academy and the module were extremely helpful in understanding the topic!
- Sun Oct 27, 2019 9:05 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: Useful YouTube videos?
- Replies: 6
- Views: 258
Re: Useful YouTube videos?
Khan Academy's article was really helpful in explaining the building-up principle.
- Sun Oct 27, 2019 9:03 pm
- Forum: Trends in The Periodic Table
- Topic: Ionization energy
- Replies: 12
- Views: 584
Re: Ionization energy
I don't think we have to know the actual equation but rather just the general trend of Ionization Energy in the periodic table.
- Sun Oct 27, 2019 12:21 am
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: HW 1D.23
- Replies: 4
- Views: 313
Re: HW 1D.23
For part c, when n=2, it has 2s and 2p are valid orbitals
in which 2s contains 1 subshell orbital (mL=0) and 2p contains 3 subshell orbitals (mL=-1,0,+1)
in which 2s contains 1 subshell orbital (mL=0) and 2p contains 3 subshell orbitals (mL=-1,0,+1)
- Sun Oct 20, 2019 11:06 pm
- Forum: Einstein Equation
- Topic: When do we use the Einstein Equation?
- Replies: 14
- Views: 761
Re: When do we use the Einstein Equation?
E = hv is used to solve for the energy of an electron.
Sometimes you are not given v (frequency) therefore you must use c = λν, substituting the v in E=hv for v = c/ λ:
so E = hc/ λ
Sometimes you are not given v (frequency) therefore you must use c = λν, substituting the v in E=hv for v = c/ λ:
so E = hc/ λ
- Sun Oct 20, 2019 11:04 pm
- Forum: Photoelectric Effect
- Topic: Speed of Light
- Replies: 29
- Views: 1511
Re: Speed of Light
The speed of light is constant at 2.998x10^8 m.s^-1
- Sun Oct 20, 2019 11:03 pm
- Forum: Heisenberg Indeterminacy (Uncertainty) Equation
- Topic: What does the H mean?
- Replies: 9
- Views: 778
Re: What does the H mean?
h is Planck's constant but h-bar is h/2pi
- Sun Oct 20, 2019 4:23 pm
- Forum: Properties of Light
- Topic: N levels
- Replies: 8
- Views: 468
Re: N levels
n levels are just the levels of energy for an electron in which n is a quantum number (n=1,2,3, etc.). When electrons increase in energy, the n increases.
- Sun Oct 20, 2019 4:20 pm
- Forum: Properties of Electrons
- Topic: Equations for Test
- Replies: 9
- Views: 329
Re: Equations for Test
I think all the equations are given to us, but we just have to know when to use them.
- Sun Oct 20, 2019 4:19 pm
- Forum: DeBroglie Equation
- Topic: De Broglie's Equation
- Replies: 17
- Views: 568
Re: De Broglie's Equation
Photons do not have mass, only momentum.
- Sat Oct 19, 2019 6:30 pm
- Forum: Heisenberg Indeterminacy (Uncertainty) Equation
- Topic: Homework Problem 1B.27
- Replies: 6
- Views: 283
Re: Homework Problem 1B.27
We use 10 for delta V
- Sat Oct 19, 2019 6:26 pm
- Forum: Heisenberg Indeterminacy (Uncertainty) Equation
- Topic: HW 1B #27
- Replies: 2
- Views: 183
Re: HW 1B #27
I used 5.00 value for delta v
Edit: Do not use 5.00 value for delta V:
Lavelle addressed this in his solution manual so we use 10 as delta v
https://lavelle.chem.ucla.edu/wp-conten ... rs_7Ed.pdf
Edit: Do not use 5.00 value for delta V:
Lavelle addressed this in his solution manual so we use 10 as delta v
https://lavelle.chem.ucla.edu/wp-conten ... rs_7Ed.pdf
- Wed Oct 16, 2019 9:19 am
- Forum: Properties of Light
- Topic: Next test
- Replies: 23
- Views: 1044
Re: Next test
I think we get an equation sheet
- Sat Oct 12, 2019 9:18 pm
- Forum: Einstein Equation
- Topic: Numbers to memorize [ENDORSED]
- Replies: 37
- Views: 4055
Re: Numbers to memorize [ENDORSED]
Helps a lot to memorize when you're doing practice problems but if you forget, there's always a cheat sheet he puts on the test for us to look at with all the constants!
- Sat Oct 12, 2019 9:17 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 3045083
Re: Post All Chemistry Jokes Here
Studying chem has shown me a lot of funny jokes
He He He
He He He
- Sat Oct 12, 2019 9:15 pm
- Forum: General Science Questions
- Topic: Rusty on High School Chem [ENDORSED]
- Replies: 347
- Views: 418704
Re: Rusty on High School Chem [ENDORSED]
I'm also really rusty but so far I think doing the practice problems he has on his Course Outlines (from the 14A website) have been extremely helpful in getting exposed to practice problems. His modules have also helped me a ton in understanding some things I haven't touched up on since 4 years ago!
- Sat Oct 12, 2019 9:12 pm
- Forum: Properties of Light
- Topic: Quantum Levels
- Replies: 9
- Views: 392
Re: Quantum Levels
I think there's a limit to how far an atom can be from the nucleus before it is lost as a "free electron."
I'm honestly not entirely sure though.
I'm honestly not entirely sure though.
- Sat Oct 12, 2019 9:10 pm
- Forum: Photoelectric Effect
- Topic: Planck's Constant
- Replies: 4
- Views: 159
Re: Planck's Constant
Online it says that he was able to derive this constant from experimental measurements from black-body radiation.
- Sat Oct 12, 2019 9:05 pm
- Forum: Einstein Equation
- Topic: E=hv
- Replies: 8
- Views: 231
Re: E=hv
h = Planck's constant (6.626*10^-34 J*s)
It'll be given to us on the front sheet of a test with all the constants, I think
It'll be given to us on the front sheet of a test with all the constants, I think
- Sat Oct 12, 2019 9:00 pm
- Forum: Properties of Light
- Topic: Speed of Light
- Replies: 41
- Views: 2746
Re: Speed of Light
The speed of light (3. 10^8 m/s) will always be a constant.
- Sat Oct 12, 2019 8:59 pm
- Forum: Properties of Electrons
- Topic: wavelike properties of an electron
- Replies: 4
- Views: 117
Re: wavelike properties of an electron
The detectors sense that the electrons had shifted to other points as opposed to a single point due to diffraction, which is demonstrated through the electron's wave-like properties.
- Sat Oct 12, 2019 8:56 pm
- Forum: DeBroglie Equation
- Topic: Concept of a wave
- Replies: 7
- Views: 523
Re: Concept of a wave
Also I believe wavelike properties are only demonstrated by objects that are extremely small.
While light does exhibit wavelike properties, the equation cannot be applied towards it.
While light does exhibit wavelike properties, the equation cannot be applied towards it.
- Sat Oct 12, 2019 8:53 pm
- Forum: Accuracy, Precision, Mole, Other Definitions
- Topic: Test 1 [ENDORSED]
- Replies: 107
- Views: 17660
Re: Test 1 [ENDORSED]
My TA said the test would be graded the same day so the grades might be up on ccle?
- Thu Oct 10, 2019 12:01 am
- Forum: Molarity, Solutions, Dilutions
- Topic: L37
- Replies: 3
- Views: 737
L37
(a) How would you prepare 1.00 L of 0.50 M HNO3 (aq) from “concentrated” (16 M) HNO3 (aq)?
(b) How many milliliters of 0.20 M NaOH(aq) could be neutralized by 100. mL of the diluted solution?
I'm not entirely sure how to begin solving this problem
(b) How many milliliters of 0.20 M NaOH(aq) could be neutralized by 100. mL of the diluted solution?
I'm not entirely sure how to begin solving this problem
- Thu Oct 03, 2019 11:27 pm
- Forum: SI Units, Unit Conversions
- Topic: Sig Fig Mistakes
- Replies: 17
- Views: 819
Re: Sig Fig Mistakes
I think you round the answer's sig fig to the smallest number at the calculation
- Thu Oct 03, 2019 11:23 pm
- Forum: Accuracy, Precision, Mole, Other Definitions
- Topic: Avogadro's Number?
- Replies: 16
- Views: 911
Re: Avogadro's Number?
Do you think we will have to memorize the Avogadro's Number for test? I am wondering if I will be given the Avogadro's Number when I get the questions that ask for atoms' number. I don't think we need to memorize the number for the test, I think Lavelle mentioned having a front sheet on tests with ...
- Thu Oct 03, 2019 11:19 pm
- Forum: Empirical & Molecular Formulas
- Topic: What decimal place to round to when taking masses from the Periodic Table?
- Replies: 19
- Views: 2928
Re: What decimal place to round to when taking masses from the Periodic Table?
Personally I use two to three decimal places but I feel like in test, we should use all of the decimals for extra accuracy in our calculation
- Thu Oct 03, 2019 11:17 pm
- Forum: Significant Figures
- Topic: How would sig figs be used in a problem?
- Replies: 7
- Views: 176
How would sig figs be used in a problem?
Would they ask "How many significant figures are in this number?"
I think I'm just confused about how this would be used practically in a problem?
I think I'm just confused about how this would be used practically in a problem?
- Thu Oct 03, 2019 11:13 pm
- Forum: SI Units, Unit Conversions
- Topic: which unit to use
- Replies: 9
- Views: 494
Re: which unit to use
I think we just use the ones called for by the problem