Search found 100 matches
- Mon Mar 07, 2022 2:38 am
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: pKa and pH [ENDORSED]
- Replies: 33
- Views: 4102
Re: pKa and pH [ENDORSED]
pH really only factors in the H+ concentration while the pKA will look at the entire equilibrium reaction.
- Mon Mar 07, 2022 2:36 am
- Forum: Kinetics vs. Thermodynamics Controlling a Reaction
- Topic: Checking-In :)
- Replies: 34
- Views: 1361
Re: Checking-In :)
Horrible!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Cannot wait for general chemistry to be over.
- Mon Mar 07, 2022 2:34 am
- Forum: Balancing Redox Reactions
- Topic: Basic Solution
- Replies: 22
- Views: 787
Re: Basic Solution
You actually don't balance H+, you balance the OH- (a good tip of balancing is make sure that the OH- is double the H20 amount)
- Mon Mar 07, 2022 2:29 am
- Forum: Balancing Redox Reactions
- Topic: Oxidized v Reduced
- Replies: 79
- Views: 3228
Re: Oxidized v Reduced
You have to write out the half reactions but if you want to remember really easily
RE-duction has electrons on the side of the RE-actants.
RE-duction has electrons on the side of the RE-actants.
- Mon Mar 07, 2022 2:25 am
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: galvanic cell diagrams
- Replies: 6
- Views: 297
Re: galvanic cell diagrams
When writing in shorthand I believe that you separate all on one side of a salt bridge with a solid line and the salt bridge is a double solid. I don't really understand where the commas play in to be honest though...
- Mon Mar 07, 2022 2:20 am
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: q=mCΔT vs q=nCΔT
- Replies: 62
- Views: 4031
Re: q=mCΔT vs q=nCΔT
It's the same thing! Just make sure that you are sure of the units that are being used, n usually refers more to molarity and concentration while m usually refers to mass, which would be in grams. As long as the units for the specific heat matches, you are good.
- Mon Mar 07, 2022 2:12 am
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Extensive Property
- Replies: 40
- Views: 1552
Re: Extensive Property
Extensive property describes something that is affected by the amount of something. Enthalpy and entropy are examples of extensive properties. Electrical potentials are not extensive.
- Mon Mar 07, 2022 2:11 am
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: galvanic versus voltaic
- Replies: 26
- Views: 1185
Re: galvanic versus voltaic
They are the same thing as each other! Galvanic = Voltaic
- Mon Mar 07, 2022 2:10 am
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Spontaneous vs nonspont
- Replies: 45
- Views: 2297
Re: Spontaneous vs nonspont
You can calculate G or you can look at the components of G, which are the enthalpy and the entropy and the temperature.
- Mon Mar 07, 2022 2:09 am
- Forum: Phase Changes & Related Calculations
- Topic: heat of vaporization vs melting
- Replies: 13
- Views: 611
Re: heat of vaporization vs melting
The steam is at a much higher temperature, and has much more energy than water, and thus can cause much more severe burns.
- Mon Mar 07, 2022 2:07 am
- Forum: Phase Changes & Related Calculations
- Topic: clarification
- Replies: 12
- Views: 689
Re: clarification
Water can be held at 100 degrees C without turning into its gaseous form. It can then be turned into gas with the addition of more heat (enthalpy of vaporization).
- Mon Mar 07, 2022 1:59 am
- Forum: General Science Questions
- Topic: Exam Format
- Replies: 16
- Views: 704
Re: Exam Format
It'll be pretty much the same exact thing as last quarter! Online and on zoom.
- Mon Mar 07, 2022 1:58 am
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Bomb calorimeter
- Replies: 17
- Views: 747
Re: Bomb calorimeter
Bomb Calorimeters are isolated systems and have their own heat capacities! That latter part took me a while to figure out.
- Mon Mar 07, 2022 1:57 am
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Positive and Negative signs
- Replies: 20
- Views: 1144
Re: Positive and Negative signs
Work: neg = work done by system, pos = work done on system
Gibbs Free Energy: neg = spontaneous, pos = not spontaneous
Enthalpy: neg = exothermic, pos = endothermic
Potential: neg = not spontaneous, pos = spontaneous
If there are any that I missed let me know!
Gibbs Free Energy: neg = spontaneous, pos = not spontaneous
Enthalpy: neg = exothermic, pos = endothermic
Potential: neg = not spontaneous, pos = spontaneous
If there are any that I missed let me know!
- Mon Mar 07, 2022 1:55 am
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: n
- Replies: 93
- Views: 3878
Re: n
It's just the number of (moles of) electrons
- Mon Mar 07, 2022 1:52 am
- Forum: Balancing Redox Reactions
- Topic: Under acidic conditions
- Replies: 16
- Views: 735
Re: Under acidic conditions
It's just that you use H+ ions instead of OH- ions to balance the half reactions!
- Mon Mar 07, 2022 1:51 am
- Forum: Calculating Work of Expansion
- Topic: Isothermal Expansion Work Equation
- Replies: 8
- Views: 405
Re: Isothermal Expansion Work Equation
The negative sign is always there! Just make sure that you put the right volumes where they're supposed to be! The final should always be above the initial
- Mon Mar 07, 2022 1:45 am
- Forum: Phase Changes & Related Calculations
- Topic: q=-q
- Replies: 91
- Views: 6148
Re: q=-q
I also remember that a lot of the times that we use this reaction, we're talking about how the increase of temp in one system affects the other. Example: when you add cold water to hot water and want to see the final temperature you have to use the qc=-qh equation.
- Sat Mar 05, 2022 5:51 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Why does Vaporization have a positive Enthalpy?
- Replies: 12
- Views: 949
Re: Why does Vaporization have a positive Enthalpy?
Think of it in the direction that you're moving, vaporization moves upwards since its getting hotter, which means that the enthalpy is positive.
- Sat Mar 05, 2022 5:50 pm
- Forum: Ideal Gases
- Topic: Which R to Use? [ENDORSED]
- Replies: 30
- Views: 1825
Re: Which R to Use? [ENDORSED]
Whenever pressure comes into play, make sure you're using the 0.08206 with atm, but if not, it is usually referring to 8.314 value. Just make sure to look at the units and seeing if they properly cancel each other out. I know it seems like a lot of work but it does help make you gain confidence.
- Sat Mar 05, 2022 5:48 pm
- Forum: Balancing Redox Reactions
- Topic: Oxidized agent
- Replies: 38
- Views: 1329
Re: Oxidized agent
The oxidizing agent is in the reduction reaction, which means that the compound that gains electrons is the oxidizing agent (because it technically oxidizes the other half reaction).
- Sat Mar 05, 2022 5:46 pm
- Forum: Administrative Questions and Class Announcements
- Topic: A Glitch Email? [ENDORSED]
- Replies: 4
- Views: 489
Re: A Glitch Email? [ENDORSED]
Yeah haha every person I know got that email, I'm not sure what it is but I guess just don't click on it?
- Sat Mar 05, 2022 5:45 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: finding value of K
- Replies: 12
- Views: 678
Re: finding value of K
You manipulate K! So however the equation is "multiplied" that is the exponent that you apply to the K value. In this case, assume that multiplying something by a negative flips it.
- Sat Mar 05, 2022 5:38 pm
- Forum: Balancing Redox Reactions
- Topic: anode vs cathode
- Replies: 77
- Views: 2897
Re: anode vs cathode
Anode is Oxidized, Cathode is reduced! if you need something to think, just remember that the vowels stick together. Also Reduced starts with R which is why it is on the RIGHT side of the R-L equation
- Sat Mar 05, 2022 5:38 pm
- Forum: Balancing Redox Reactions
- Topic: anode vs cathode
- Replies: 77
- Views: 2897
Re: anode vs cathode
Anode is Oxidized, Cathode is reduced! if you need something to think, just remember that the vowels stick together. Also Reduced starts with R which is why it is on the RIGHT side of the R-L equation
- Sat Mar 05, 2022 5:37 pm
- Forum: Balancing Redox Reactions
- Topic: Balancing O and H
- Replies: 19
- Views: 890
Re: Balancing O and H
They'll specify for you if it is basic or if it is acidic but just know that for acidic, add as many water molecules as oxygen you need on one side, and then just balance the other side with H+ ions. For basic solutions, add twice as much OH- that you need on the side that doesn't have enough oxygen...
- Sat Mar 05, 2022 5:34 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: What is the Le Chatelier's Principle
- Replies: 30
- Views: 1047
Re: What is the Le Chatelier's Principle
Think of it like equilibrium, if I add something to one side, the other side is going to have a boost in production, and the concentration for the reactants on the same side will be lower in comparison.
- Sat Mar 05, 2022 5:32 pm
- Forum: Concepts & Calculations Using Second Law of Thermodynamics
- Topic: 5/2 R and 3/2R
- Replies: 37
- Views: 1935
Re: 5/2 R and 3/2R
Yeah you're right, we only really use them for ideal gases, and they also must be monatomic too since diatomic is 7/2R and 5/2R instead.
- Sat Mar 05, 2022 5:30 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: Entropy between two molecules
- Replies: 5
- Views: 271
Re: Entropy between two molecules
Polyethylene is a solid!
It's basically like explaining that ice or rock has a lower entropy than water vapor or air, the gas is more "disordered" and thus has a higher entropy
It's basically like explaining that ice or rock has a lower entropy than water vapor or air, the gas is more "disordered" and thus has a higher entropy
- Sat Mar 05, 2022 5:29 pm
- Forum: Balancing Redox Reactions
- Topic: oxidation numbers
- Replies: 25
- Views: 1733
Re: oxidation numbers
You just look at the atoms attached to it and set the charges = 0 (or whatever the charge of the molecule is)
MgO2 would be like (x) - (2*O2) = 0
and we know O2 = -2, so Mg's oxidation number must be 4
MgO2 would be like (x) - (2*O2) = 0
and we know O2 = -2, so Mg's oxidation number must be 4
- Sat Mar 05, 2022 5:27 pm
- Forum: Calculating Work of Expansion
- Topic: Reversible/irreversible
- Replies: 6
- Views: 268
Re: Reversible/irreversible
It honestly is just kind of what it sounds like, reversible would usually be done in an isolated system where nothing can leave or be added and so everything stays the exact same as it is initially, whereas irreversible can also be like in this environment, but usually is less efficient and faster.
- Sat Mar 05, 2022 5:25 pm
- Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
- Topic: What does "n" stand for
- Replies: 78
- Views: 4088
Re: What does "n" stand for
n stands for the number of moles but for electrochemistry, it stands for the amount of electrons used up in each half reaction
- Sat Mar 05, 2022 5:24 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Enthalpy
- Replies: 8
- Views: 428
Re: Enthalpy
It ALWAYS helps me to look at the units of the calculation and see what I should be having as a result, it shows me which numbers I can plug into where, which has shown me which equations I should use to calculate problems.
- Sat Mar 05, 2022 5:22 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Inert Gas
- Replies: 15
- Views: 767
Re: Inert Gas
Inert is just a filler gas that doesn't really react, and thus doesn't contribute anything to the reaction
- Sat Mar 05, 2022 5:21 pm
- Forum: Balancing Redox Reactions
- Topic: Oxidizing and Reducing Agent
- Replies: 18
- Views: 797
Re: Oxidizing and Reducing Agent
I always found it just the easiest to see the reactant of the reduction (oxidizing agent) and the reactant of the oxidation (reducing agent). It's just an opposite thing.
- Sat Mar 05, 2022 5:20 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: How voume increase effects reaction
- Replies: 13
- Views: 573
Re: How voume increase effects reaction
If you decrease the volume, the reaction with more moles will start working overtime, and thus the reaction that produces less moles will actually have an increase. Vice versa
- Sat Mar 05, 2022 5:18 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Summary of Le Chatelier's Principle
- Replies: 4
- Views: 482
Re: Summary of Le Chatelier's Principle
Thanks! I keep on forgetting how affecting the concentrations will make differences, so this broke that concept down really well!
- Sat Mar 05, 2022 5:17 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: SHE explanation
- Replies: 5
- Views: 265
Re: SHE explanation
an SHE is basically just what you use to find the voltage/potential of a specific reaction. You use it with another half reaction because it will make it so that you only have to focus on the one you're looking for (in like a laymans term)
- Sat Mar 05, 2022 5:16 pm
- Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
- Topic: spontaneity
- Replies: 43
- Views: 1701
Re: spontaneity
Yep! If delta G is negative, that means there's an excess of energy that can be used, which means that it was spontaneous, and because of the equation G=-nfE, E must also be positive for it to be spontaneous
- Mon Jan 17, 2022 7:27 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Ka vs pKa
- Replies: 16
- Views: 670
Re: Ka vs pKa
Ka is the actual constant and pKA is the negative log of that
- Mon Jan 17, 2022 7:26 pm
- Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
- Topic: Achieve #5 - how to calculate concentration of initial base
- Replies: 2
- Views: 201
Re: Achieve #5 - how to calculate concentration of initial base
This is because if you set up your icebox, you will find that the initial concentration of the reactant usually gets 'x' subtracted from it to show how it was used up during the reaction toward equilibrium. That is why when you find the final equilibrium concentration, you have to add the amount tha...
- Mon Jan 17, 2022 7:24 pm
- Forum: General Science Questions
- Topic: Midterm 1 [ENDORSED]
- Replies: 69
- Views: 5406
Re: Midterm 1 [ENDORSED]
the first midterm is said to be on wednesday, feb 2nd
- Mon Jan 17, 2022 7:23 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: ICE tables
- Replies: 8
- Views: 587
Re: ICE tables
No you omit H20 in the ICE tables because it is almost always in excess and so it will not contribute to the reaction's concentrations
- Mon Jan 17, 2022 7:21 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: K to pH
- Replies: 10
- Views: 595
Re: K to pH
-log[Ka] = pH
-log[Kb] = pOH
-log[Kc] = pH or pOH (depends on whether it is a weak acid or base reaction
-log[Kb] = pOH
-log[Kc] = pH or pOH (depends on whether it is a weak acid or base reaction
- Sun Jan 09, 2022 5:28 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: How do you know which ions to include in fully dissociated ionic compounds in the equilibrium constant?
- Replies: 3
- Views: 163
Re: How do you know which ions to include in fully dissociated ionic compounds in the equilibrium constant?
Only the ones that are both aqueous as reactants AND as products can we say are "fully dissociated" and we use in the constant calculation
- Sun Jan 09, 2022 5:26 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: When Q=K
- Replies: 73
- Views: 3531
Re: When Q=K
Yep! When the reaction quotient is the same thing as the equilibrium constant, then the reaction is at equilibrium.
- Sun Jan 09, 2022 5:25 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Basic Definition of Le Chatelier's Principle?
- Replies: 20
- Views: 1466
Re: Basic Definition of Le Chatelier's Principle?
Le Chatelier's principle is pretty simple overall, it just describes that in a closed system, manipulation to a part of the reaction (whether forward or backward) will somehow affect another aspect, since nothing can really be added or taken away in that reaction.
- Sun Jan 09, 2022 5:18 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Q vs. K
- Replies: 36
- Views: 1292
Re: Q vs. K
Q refers to the overall reaction quotient BUT does not refer to the equilibrium constant. Think of Q as K, but without having actually gotten to equilibrium, thus the number that you get wouldn't be the equilibrium constant. Since this is the case though, it can be calculated at any point in the rea...
- Sun Jan 09, 2022 5:15 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Achieve #3
- Replies: 4
- Views: 187
Re: Achieve #3
Also a tip if you've already worked through it or not, make sure that the (2x) is squared, so it should be 4x^2 or (2x)^2 rather than just 2x^2. Hope this also helps
- Thu Dec 02, 2021 4:08 pm
- Forum: Hybridization
- Topic: sp^3 vs 2sp^3
- Replies: 28
- Views: 1368
Re: sp^3 vs 2sp^3
You could have a different number in front of the hybridization, but since we're really only dealing with group 2 most of the time, you don't really need to add it in front. It's just more for specificity.
- Thu Dec 02, 2021 4:06 pm
- Forum: Bronsted Acids & Bases
- Topic: HF
- Replies: 5
- Views: 286
Re: HF
Well technically CH2FCOOH is also a weak acid too, so we're all talking about in terms of weak acids. However, the Flourine in CH2FCOOH delocalizes the electrons further so that in the conjugate base, when the H is taken off, the structure is more stable and its electrons are delocalized more.
- Thu Dec 02, 2021 4:04 pm
- Forum: Lewis Acids & Bases
- Topic: pKa
- Replies: 31
- Views: 1425
Re: pKa
With pKa, it's similar to pH in the sense of its trends. The lower the pH and pKa, the stronger the acid and higher the [H3O+] for pH and higher the [Ka] for pKa.
- Thu Dec 02, 2021 4:02 pm
- Forum: Conjugate Acids & Bases
- Topic: Final [ENDORSED]
- Replies: 6
- Views: 483
Re: Final [ENDORSED]
I'm not exactly sure this time around but apparently in years prior, our TA told us that it was 30 6-point questions and was out of 180 points. For us, it's out of 140 but I'm assuming that we might also have around 30 questions that are mixed with 4 and 8 points? Or maybe 25. It could very well be ...
- Thu Dec 02, 2021 4:00 pm
- Forum: Conjugate Acids & Bases
- Topic: Conjugate meaning
- Replies: 12
- Views: 632
Re: Conjugate meaning
The conjugate acid of a base, is for example NH3. If NH3 were to be put in a reaction with water, it would form NH4+ and OH-. The NH4+ is a conjugate acid, since it is the acid that forms from the base NH3 in water.
Hope that makes sense!
Hope that makes sense!
- Mon Nov 22, 2021 6:59 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Ligands
- Replies: 6
- Views: 267
Re: Ligands
Hello! Ligands are simply just things that bind to a central atom. They are just used as ligands because they may have multiple binding sites and also because they are full molecules. Mostly though it's just jargon.
- Mon Nov 22, 2021 6:57 pm
- Forum: Lewis Acids & Bases
- Topic: hybridization
- Replies: 8
- Views: 464
Re: hybridization
The hybridization of BeCl2 is SP
- Mon Nov 22, 2021 6:46 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Pi bonds
- Replies: 46
- Views: 1789
Re: Pi bonds
Sigma bond = single bonds
Pi bonds = anything thats more than that.
AKA
Single bond = 1 sigma bond
Double bond = 1 sigma bond + 1 pi bond
Triple bond = 1 sigma bond + 2 pi bonds
Quadruple bond = 1 sigma bond + 3 pi bonds
Pi bonds = anything thats more than that.
AKA
Single bond = 1 sigma bond
Double bond = 1 sigma bond + 1 pi bond
Triple bond = 1 sigma bond + 2 pi bonds
Quadruple bond = 1 sigma bond + 3 pi bonds
- Mon Nov 22, 2021 6:44 pm
- Forum: Student Social/Study Group
- Topic: Fave food
- Replies: 266
- Views: 55744
Re: Fave food
I love french onion soup. I will die for it. Literally.
- Mon Nov 22, 2021 6:44 pm
- Forum: Calculating the pH of Salt Solutions
- Topic: pH formula?
- Replies: 69
- Views: 4900
Re: pH formula?
you just use the logarithm equation he gave us in class today! make sure you use the negative though since we're taking the log of a concentration which is really small, so it would be at a negative power.
- Sun Nov 14, 2021 5:10 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: LDF
- Replies: 19
- Views: 1661
Re: LDF
Bigger atoms = more electrons = stronger LDF because that's how they interact.
- Sun Nov 14, 2021 5:09 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Achieve HW #10
- Replies: 18
- Views: 649
Re: Achieve HW #10
F is the most electronegative, and so they would attract the electrons the most, meaning that they have the most negative charge within the molecule.
- Sun Nov 14, 2021 5:08 pm
- Forum: Resonance Structures
- Topic: multiple resonance structures
- Replies: 9
- Views: 451
Re: multiple resonance structures
Most of the time it depends, if we are talking about hypervalent models, then you try to go for many different combinations, but still try to minimize formal charges. With regular octet structures you try to make it so that the central atom does not have any formal charges. A good rule of thumb is j...
- Sun Nov 14, 2021 5:02 pm
- Forum: Ionic & Covalent Bonds
- Topic: Bond strengths
- Replies: 9
- Views: 414
Re: Bond strengths
Ionic bonds form through positively and negatively charged ions. Thus, because it is just by that rule, it is easier to create networks of ionic bonds. This lattice is overall stronger than the covalent bonds, and is harder to break.
- Sun Nov 14, 2021 4:59 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: AXE Notation
- Replies: 33
- Views: 1875
Re: AXE Notation
A will almost always be one, so it is just denoted by A since there is no point in writing A1.
X denotes the amount of bonding pairs on the central atom.
E denotes the amount of lone pairs on the central atom.
Hope this helps!
X denotes the amount of bonding pairs on the central atom.
E denotes the amount of lone pairs on the central atom.
Hope this helps!
- Sun Nov 07, 2021 12:36 pm
- Forum: Electronegativity
- Topic: Achieve #15
- Replies: 4
- Views: 273
Re: Achieve #15
Halides are just the second to last group (column), right before noble gases, in the periodic table.
- Sun Nov 07, 2021 12:35 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Bent vs Linear
- Replies: 23
- Views: 2072
Re: Bent vs Linear
To add on, the bent shape is created because of its tetrahedral properties, so you can think of bent to have that similar shape. Pretend you were to take off two molecules in a tetrahedral shape, no matter where you did it, it would look like a bent molecule.
- Sun Nov 07, 2021 12:33 pm
- Forum: Ionic & Covalent Bonds
- Topic: HW Weeks 5 & 6 Achieve #20
- Replies: 6
- Views: 281
Re: HW Weeks 5 & 6 Achieve #20
Yep, all molecules have London Dispersion Forces, and can then have different ones like dipole-dipole or ionic or etc.
- Sun Nov 07, 2021 12:29 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Final
- Replies: 6
- Views: 350
Re: Final
I'm unsure, I think it might be similar to how the midterms are administered, but I also remember that the final is being taken at the same time by everyone, so it might be online on zoom. Probably just email or ask your TA though, they should be able to give you the best answer.
- Mon Nov 01, 2021 4:06 pm
- Forum: Bond Lengths & Energies
- Topic: How to Determine Bond Length
- Replies: 11
- Views: 1534
Re: How to Determine Bond Length
You honestly don't know accurately so you kind of just have to use your intuition about what you already know about those atoms according to their nuclear charge and radius.
- Mon Nov 01, 2021 4:04 pm
- Forum: Student Social/Study Group
- Topic: Halloween!!!
- Replies: 73
- Views: 5119
Re: Halloween!!!
I dressed up as wet floor sign and poured water on the floor with my squirt guns/water bottle. Incredible costume. Got many compliments.
- Mon Nov 01, 2021 4:03 pm
- Forum: Student Social/Study Group
- Topic: Study music
- Replies: 59
- Views: 8133
Re: Study music
This sounds stupid, but work with someone who will keep you accountable while using a modified version of the pomodoro method. Set a timer for each other and don't speak, and then talk for a bit, and then set another timer. If I stick to it, it always works for me and I feel like I get a lot of work...
- Mon Nov 01, 2021 4:02 pm
- Forum: Ionic & Covalent Bonds
- Topic: How do intermolecular forces lead to liquid and solid formations?
- Replies: 2
- Views: 186
Re: How do intermolecular forces lead to liquid and solid formations?
More electrons usually mean that there will be more van der waals forces, which creates a stronger and more tightly compact atom/molecule. That's why the larger atoms with more electrons tend to be solids.
- Mon Nov 01, 2021 3:57 pm
- Forum: Bond Lengths & Energies
- Topic: London Dispersion Forces
- Replies: 8
- Views: 490
Re: London Dispersion Forces
I don't know if you remember the example he gave, but N2 is a really good one that represents induced dipole-induced dipole bonds.
- Mon Nov 01, 2021 3:56 pm
- Forum: Bond Lengths & Energies
- Topic: Bond length in double vs single [ENDORSED]
- Replies: 57
- Views: 3722
Re: Bond length in double vs single [ENDORSED]
Hello! We covered this in lecture today, but shorter bond lengths mean that there is a stronger attraction, while longer ones usually tend to mean that they are weaker. Also double bonds are rarely broken for reactions, while longer and single ones are. And don't forget, electron electron repulsion ...
- Mon Nov 01, 2021 3:54 pm
- Forum: Lewis Structures
- Topic: Memorizing Acids/Bases?
- Replies: 7
- Views: 289
Re: Memorizing Acids/Bases?
You can just think of any resultant anion as an acid "A to A" and cation to base (no mnemonic for that but it's just there). Other than the extent of that though, you don't really have to memorize the lewis acids and bases.
- Mon Nov 01, 2021 3:52 pm
- Forum: Formal Charge and Oxidation Numbers
- Topic: Lone Pairs
- Replies: 6
- Views: 317
Re: Lone Pairs
I get that it's a little confusing, but most of the times, in an equation, you refer to the amount of electrons that are lone pairs. Also they kind of just call it that because it's almost always found as pairs (if they weren't it'd be pretty unstable like how it would be in a radical).
- Mon Nov 01, 2021 3:48 pm
- Forum: Ionic & Covalent Bonds
- Topic: Delocalized
- Replies: 6
- Views: 375
Re: Delocalized
It is simply referring to the electron within an atom with resonance. You can't really "localize" it, which is why it's called that
- Mon Nov 01, 2021 3:47 pm
- Forum: Ionic & Covalent Bonds
- Topic: Dipole-Dipole Bonds
- Replies: 5
- Views: 395
Re: Dipole-Dipole Bonds
In the same way, a hydrogen bond is technically a dipole-dipole bond, but just especially between hydrogens. The concept remains the same though, if that helps you visualize it in your head.
- Sat Oct 23, 2021 6:34 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: Amplitude and Energy
- Replies: 14
- Views: 768
Re: Amplitude and Energy
Stop because all I remember was that he said that the amplitude is directly proportional to the intensity AND THATS IT :-|||||||. I think amplitude squared is light intensity though
- Sat Oct 23, 2021 6:31 pm
- Forum: Trends in The Periodic Table
- Topic: Ionization Energy Periodic Trend
- Replies: 6
- Views: 319
Re: Ionization Energy Periodic Trend
ionization energy is simply how much energy it will take to remove an electron from an atom. Most of the time, in the cases of non-metals, it will be harder to take away an electron, mostly because they will try to gain one to fill their valence shells. This is all except for oxygen, between Nitroge...
- Sat Oct 23, 2021 6:27 pm
- Forum: Quantum Numbers and The H-Atom
- Topic: Degeneracy in elements
- Replies: 4
- Views: 442
Re: Degeneracy in elements
the only other degenerate ion would be He+ and that is because there is similarly only one electron in that atom, while still in the level one shell
- Sat Oct 23, 2021 6:26 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: Midterm Scores
- Replies: 16
- Views: 657
Re: Midterm Scores
Don't worry too much, we'll all probably be notified in the near future through email! Or you can just ask your TA in the discussion if he hasn't posted it by then
- Sat Oct 23, 2021 6:25 pm
- Forum: Properties of Light
- Topic: Achieve Hw #8
- Replies: 12
- Views: 580
Re: Achieve Hw #8
Hey! just use the equation frequency = R((1/nfinal^2)-(1/ninitial^2)), and remember, frequency is speed of light/wavelength!
- Sat Oct 23, 2021 6:18 pm
- Forum: Einstein Equation
- Topic: how to find eV
- Replies: 33
- Views: 1672
Re: how to find eV
I also agree with what everyone's saying, I would also just add that if you need any of these constants, or just need somewhere to find them, I would use the constants equation sheet that they gave us. it is all on there!
- Sun Oct 17, 2021 4:19 pm
- Forum: Properties of Light
- Topic: Respondus Question
- Replies: 17
- Views: 714
Re: Respondus Question
I believe the correct answer to the question is UV-A light, because longer wavelength is less energy. The smaller the wavelengths get in the EM spectrum, the more dangerous and hazardous they are to organic things because of their higher ionization energy. This means that a longer wavelength (UV-A) ...
- Sun Oct 17, 2021 4:16 pm
- Forum: Heisenberg Indeterminacy (Uncertainty) Equation
- Topic: Module Question
- Replies: 8
- Views: 379
Re: Module Question
Yeah, you would want to divide Avogadro's number!
- Sun Oct 17, 2021 4:13 pm
- Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
- Topic: Rydberg's constant
- Replies: 6
- Views: 720
Re: Rydberg's constant
It's just different based upon whether you're using the equation with c/lambda, or if you are setting it simply equal to lambda, because if you divide the 3.289e-15 constant by the speed of light, you should find the other constant value!
- Sun Oct 17, 2021 4:11 pm
- Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
- Topic: Equation
- Replies: 6
- Views: 334
Re: Equation
Yeah, agreeing with everyone else, you would find the value of E_5 and E_2 separately with the same equation, and then you would be able to subtract E_5 from E_2 and it would give you the answer!
- Sun Oct 17, 2021 4:09 pm
- Forum: DeBroglie Equation
- Topic: Achieve HW #17
- Replies: 4
- Views: 246
Re: Achieve HW #17
Kinda, the reason why it says to treat it as a particle is so that you divide the mass of the diatomic hydrogen by avogadro's number to find the final mass of ONE particle. Then you just have to make sure to convert that number into kg from g, and then you can plug it into lambda=h/(mv). Hope this h...
- Thu Oct 07, 2021 8:23 pm
- Forum: Properties of Light
- Topic: General Energy Question
- Replies: 8
- Views: 318
Re: General Energy Question
I don't know if this actually clarifies anything because I'm probably in the same boat as you are, but wouldn't representing energy graphically be the same, just with two variables? Instead of sketching only wavelength and frequency, you would represent them interacting with each other, which is wha...
- Thu Oct 07, 2021 8:21 pm
- Forum: Photoelectric Effect
- Topic: Energy and frequency
- Replies: 11
- Views: 388
Re: Energy and frequency
Also! I don't know if anyone posted this already but make sure you remember that because of the equation E=hv, wavelength is INVERSELY proportional to the energy. Same with frequency. The longer the wavelength, the smaller the energy and vice versa. This goes the same as with frequency.
- Thu Oct 07, 2021 8:18 pm
- Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
- Topic: 1A #15
- Replies: 4
- Views: 238
Re: 1A #15
Hello! Going off of the previous answer, you also should use the equation [c/(lambda)]=[R(1/(n final)^2)-(1/(n initial)^2)]. That was kind of a disgusting equation but I swear it works! Also make sure to convert to the correct units. You should get the answer n=3, if you need further help just let m...
- Thu Oct 07, 2021 8:15 pm
- Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
- Topic: atomic spectra question
- Replies: 6
- Views: 299
Re: atomic spectra question
This isn't exactly an answer, more of another question.
What do the n values mean when we say they're jumping and dropping certain levels? Like what does n1, n2, n3, n4 actually mean? Or is this unimportant for us to know about?
Thank you!
What do the n values mean when we say they're jumping and dropping certain levels? Like what does n1, n2, n3, n4 actually mean? Or is this unimportant for us to know about?
Thank you!
- Thu Oct 07, 2021 8:04 pm
- Forum: Significant Figures
- Topic: Significant figures requirement
- Replies: 22
- Views: 1745
Re: Significant figures requirement
In terms of significant figures, you always want to take into account the smallest amount of significant figures a number will have in an equation. For example, 3.0m x 1.45678m = 4.37034 = 4.4 m^2 Why is this 4.4m^2 instead of 4.37034m or 4.37 m ? Looking at the 3.0, we can see there are 2 signific...
- Thu Oct 07, 2021 7:58 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Advice from a Medical Student - Part II [ENDORSED]
- Replies: 298
- Views: 366595
Re: Advice from a Medical Student - Part II [ENDORSED]
Hi Ashley! It feels so surreal actually typing this out, knowing that you might respond, while also believing that it could just get lost in the sea of all the other thirsty pre-meds who similarly (and shamelessly) need any help they can get. It seems so daunting and hard all the time, how do you c...
- Thu Sep 30, 2021 9:46 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Saying Thank You to Dr. Lavelle
- Replies: 490
- Views: 716154
Re: Saying Thank You to Dr. Lavelle
I have been in this class for a few days now but I thought it would be cool to write a letter of appreciation at the beginning, and then redo it for my final community post as well. To be quite frank, I thought the class would be so difficult to get to know someone's teaching style and personality, ...
- Thu Sep 30, 2021 9:43 pm
- Forum: Administrative Questions and Class Announcements
- Topic: 14B Enrollment [ENDORSED]
- Replies: 67
- Views: 20315
Re: 14B Enrollment [ENDORSED]
I'm a little lost on how this works, can someone explain how enrollment works in "non-orientation" style. Also, is it an acceptable thing to do 14b and 7a at the same time along with 30b and a cluster? Just wondering, thanks!
- Thu Sep 30, 2021 9:40 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Advice from a Medical Student - Part II [ENDORSED]
- Replies: 298
- Views: 366595
Re: Advice from a Medical Student - Part II [ENDORSED]
Hi Ashley! It feels so surreal actually typing this out, knowing that you might respond, while also believing that it could just get lost in the sea of all the other thirsty pre-meds who similarly (and shamelessly) need any help they can get. It seems so daunting and hard all the time, how do you co...
- Thu Sep 30, 2021 9:36 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 4108550
Re: Post All Chemistry Jokes Here
OK THIS IS GONNNA BE GOOD (I saw it on Reddit somewhere long time ago)
A photon walks into a hotel and the front desk manager asks it, "do you need any assistance with your luggage?"
the photon responds, "no, I'm travelling light"
A photon walks into a hotel and the front desk manager asks it, "do you need any assistance with your luggage?"
the photon responds, "no, I'm travelling light"
- Thu Sep 30, 2021 9:29 pm
- Forum: Student Social/Study Group
- Topic: Culinary Chemistry
- Replies: 239
- Views: 47857
Re: Culinary Chemistry
Hey All! I'm unsure if someone has said this already, or if this even relates, but a trick I do know in the kitchen is when it comes to preparing... (drumroll) ONIONS! It's incredibly easy to prevent the onslaught of tears, all you have to do is place a wet paper towel on your cutting board while yo...