Search found 102 matches
- Fri Mar 12, 2021 12:55 pm
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: Sapling #15
- Replies: 4
- Views: 337
Re: Sapling #15
This is how I did #15! Hope this helps!!
- Fri Mar 12, 2021 12:52 pm
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: Sapling #14
- Replies: 2
- Views: 159
Re: Sapling #14
This is how I did it! Hope this helps!!
- Fri Mar 12, 2021 12:51 pm
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: sapling week 9/10 #15
- Replies: 3
- Views: 295
Re: sapling week 9/10 #15
This is how I did it! Hope this helps!!
- Fri Mar 12, 2021 12:50 pm
- Forum: Reaction Mechanisms, Reaction Profiles
- Topic: Sapling Week 9/10 #16
- Replies: 13
- Views: 696
Re: Sapling Week 9/10 #16
Here is how I did it! Hope this helps!
- Fri Mar 12, 2021 12:47 pm
- Forum: Reaction Mechanisms, Reaction Profiles
- Topic: Sapling #13 Weeks 9/10
- Replies: 7
- Views: 458
Re: Sapling #13 Weeks 9/10
Here is how I did it! Hope this helps.
- Sun Mar 07, 2021 11:54 am
- Forum: General Rate Laws
- Topic: Youtube Review
- Replies: 17
- Views: 979
Re: Youtube Review
I really like Khan Academy!
- Sun Mar 07, 2021 11:53 am
- Forum: Balancing Redox Reactions
- Topic: Balancing Reactions Help
- Replies: 5
- Views: 328
Re: Balancing Reactions Help
I had trouble balancing as well and I just watched a youtube video on how to do it and just did a bunch of practice problems. Hope this helps!
- Sun Mar 07, 2021 11:52 am
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Combining K's
- Replies: 7
- Views: 496
Re: Combining K's
You add when they are state properties, but since K or Q arent, then you cannot just add, it is more complicated than that since the path taken MATTERS. Hope this helps!
- Sun Mar 07, 2021 11:50 am
- Forum: Method of Initial Rates (To Determine n and k)
- Topic: graphs and order
- Replies: 19
- Views: 939
Re: graphs and order
And you just tell if it is either of the three orders by looking at the graph and seeing which type of graph it is?
- Sun Mar 07, 2021 11:48 am
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: Concentration Cells at Equilibrium
- Replies: 7
- Views: 395
Re: Concentration Cells at Equilibrium
No, they aren't always at equilibrium, as they create a voltage when reaching equilibrium.
- Sun Feb 28, 2021 1:02 pm
- Forum: Balancing Redox Reactions
- Topic: Sapling 7/8 #17
- Replies: 8
- Views: 505
Re: Sapling 7/8 #17
Remember that the standard cell potential is zero for S.H.E! Hope this helps.
- Sun Feb 28, 2021 1:00 pm
- Forum: Balancing Redox Reactions
- Topic: Sapling #5
- Replies: 9
- Views: 583
Re: Sapling #5
Make sure your zeros are not Os because that is what got me stuck. Hope this helps!!
- Sun Feb 28, 2021 12:58 pm
- Forum: Balancing Redox Reactions
- Topic: Sapling week 7/8 #4
- Replies: 9
- Views: 519
Re: Sapling week 7/8 #4
Hi, this is how I was able to solve it! Hope this helps!
- Sun Feb 28, 2021 12:54 pm
- Forum: Balancing Redox Reactions
- Topic: Homework question 3
- Replies: 2
- Views: 186
Re: Homework question 3
I had a different reaction than you but this is what I did for question 3. Hope this helps!
- Sun Feb 28, 2021 12:48 pm
- Forum: Balancing Redox Reactions
- Topic: Sapling Week 8 #18
- Replies: 5
- Views: 328
Re: Sapling Week 8 #18
You are very close. The answer is 4Fe+3O2+6H2O⟶2Fe2O3∙3H2O. Hope this helps!!
- Sat Feb 20, 2021 3:38 pm
- Forum: Concepts & Calculations Using Second Law of Thermodynamics
- Topic: Sapling (week 5 and 6) #2
- Replies: 7
- Views: 540
Re: Sapling (week 5 and 6) #2
You first have to convert J/s to J/Hr and then divide (J/Hr)/(Degree in C + 273K) to get the units J/K*Hr. Hope this helps!
- Sat Feb 20, 2021 3:22 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Solids and Liquids?
- Replies: 26
- Views: 1484
Re: Solids and Liquids?
I had this same question too and was told it's only gases, not aqueous solutions too.
- Sat Feb 20, 2021 3:18 pm
- Forum: Balancing Redox Reactions
- Topic: Chemical Reactions and Electrical Energy
- Replies: 6
- Views: 347
Re: Chemical Reactions and Electrical Energy
How I like to think about this is that it is a battery and there is an exchange of electrons, and, therefore this movement of electrons is electricity. Hope this helps!
- Sat Feb 20, 2021 3:14 pm
- Forum: Balancing Redox Reactions
- Topic: Sapling #3
- Replies: 4
- Views: 392
Re: Sapling #3
I was wondering the same thing! I'm not sure if we need to know this or not.
- Sun Feb 14, 2021 1:07 pm
- Forum: Concepts & Calculations Using Second Law of Thermodynamics
- Topic: Sapling Week 6 Question 1
- Replies: 6
- Views: 373
Re: Sapling Week 6 Question 1
Molecules that are polar have entropy! Hope this helps.
- Fri Feb 12, 2021 12:50 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Sapling #14
- Replies: 6
- Views: 285
Re: Sapling #14
Make sure you convert the 57.91 J·mol−1·K−1 to kJ/mol*k and then plug it into the T=deltaH/deltaS equation to solve to T. Then since the answer is in K, you have to subtract 273K to get the final answer in Celsius. Hope this helps!
- Fri Feb 12, 2021 12:46 pm
- Forum: Calculating Work of Expansion
- Topic: R constant
- Replies: 4
- Views: 213
Re: R constant
I would use what is on the constants sheet to be safe! Hope this helps!
- Fri Feb 12, 2021 12:45 pm
- Forum: Entropy Changes Due to Changes in Volume and Temperature
- Topic: Question about Sapling #6 Week 5/6
- Replies: 6
- Views: 305
Re: Question about Sapling #6 Week 5/6
How I thought about it is that there are two things happening, the first is a change in volume and also a temperature change. The total entropy is equal to Sv+St. Hope this helps!
- Fri Feb 12, 2021 12:43 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Sapling Week 5 and 6 #19
- Replies: 4
- Views: 290
Re: Sapling Week 5 and 6 #19
Remember that Q=[products]^coefficient/[reactants][reactants]^coefficient. And then use the equation deltaG=RTlnQ+deltaGstandard! Hope this helps. Also, watch out for the units.
- Sun Feb 07, 2021 1:07 pm
- Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
- Topic: Sapling #16
- Replies: 6
- Views: 345
Re: Sapling #16
You know that deltaE is equal to q-w(w is neg bc work out of system). You then convert kcal to kJ to find q, then you do q-w(which is what was given to you). Hope this helps!
- Sat Feb 06, 2021 3:21 pm
- Forum: Concepts & Calculations Using Second Law of Thermodynamics
- Topic: Entropy = 0
- Replies: 6
- Views: 253
Re: Entropy = 0
Yes, I assumed that when he said O2, he also meant that other diatomic particles would approach zero since there are 2 identical elements and there cannot be a lot of variations in their reactions. Hope this helps!
- Sat Feb 06, 2021 3:17 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Can heat capacities be negative?
- Replies: 52
- Views: 13993
Re: Can heat capacities be negative?
I was wondering the same thing because when I looked it up online it said "Negative heat capacity would mean that when a system loses energy, its temperature decreases", so it is possible? I'm not really sure if that is the correct answer though!
- Sat Feb 06, 2021 3:13 pm
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: Phase Change
- Replies: 6
- Views: 257
Re: Phase Change
Yes, I think it can be both! It just depends on what the system is and what is happening. Hope this helps!
- Sun Jan 31, 2021 6:56 pm
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: R Constant
- Replies: 91
- Views: 6377
Re: R Constant
I just look at the units and see what matches up with it from the constant sheet given to us! Hope this helps.
- Sun Jan 31, 2021 6:55 pm
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: Syllabus Problems
- Replies: 6
- Views: 194
Re: Syllabus Problems
I think the rest of the quarter will be on thermodynamics(so thermochemistry included) since that is the main topic we are covering in 14b. Hope this helps!
- Fri Jan 29, 2021 3:30 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Textbook problem 6.61
- Replies: 7
- Views: 311
Re: Textbook problem 6.61
Only gas and aqueous entities affect K. Liquids and Solids do not. Hope this helps.
- Fri Jan 29, 2021 3:26 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Making X negligible
- Replies: 34
- Views: 1470
Re: Making X negligible
It is the 5% rule, which is the same method as finding percent ionization! Hope this helps!
- Fri Jan 29, 2021 3:25 pm
- Forum: Phase Changes & Related Calculations
- Topic: when to assume x is insignificant
- Replies: 86
- Views: 7362
Re: when to assume x is insignificant
Use the 5% rule which is the same way of doing percent ionization! Hope this helps!
- Thu Jan 28, 2021 9:05 am
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: textbook 6A. 23
- Replies: 3
- Views: 191
Re: textbook 6A. 23
Since you need to know the concentration which is mol/liters, it will be .0025mol/.1L which is 0.025M. as the concentration of [Ba(OH2)] and [Ba+], the concentration of [OH-] is 2*.025M since there are two [OH-]. Hope this helps!
- Fri Jan 22, 2021 10:55 am
- Forum: Phase Changes & Related Calculations
- Topic: Vapor vs gas
- Replies: 121
- Views: 11713
Re: Vapor vs gas
Yes, they are the same thing and are used interchangeably! Hope this helps.
- Fri Jan 22, 2021 10:53 am
- Forum: Phase Changes & Related Calculations
- Topic: State Property
- Replies: 71
- Views: 3227
Re: State Property
An example of a state property is delta H, as it doesn't depend on the path to get this change, but rather the initial and final. Hope this helps!
- Fri Jan 22, 2021 10:50 am
- Forum: Phase Changes & Related Calculations
- Topic: Constant Temperature
- Replies: 20
- Views: 816
Re: Constant Temperature
Yes, so even though there is heat being added, the temperature does not change since the heat added is breaking the bonds. Hope this helps!
- Tue Jan 19, 2021 6:28 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Verify assumption
- Replies: 3
- Views: 256
Re: Verify assumption
It is called the "5% rule" where it is (concentration you found/given)*100% (has to be less than 5% in order to use the assumption), which is the same process as finding the percent ionization. Hope this helps!
- Tue Jan 19, 2021 6:25 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Comparing pKb Values
- Replies: 4
- Views: 178
Re: Comparing pKb Values
A lower pKb value indicates a stronger base! Hope this helps!
- Sun Jan 17, 2021 1:37 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Adding together two equilibrium equations
- Replies: 5
- Views: 396
Re: Adding together two equilibrium equations
They are added together. The examples we had in sapling added together 1/K or K^2 to show how if you reverse the reaction or double its moles then it still be added all together, but in a trickier way! Hope this helps.
- Sun Jan 17, 2021 1:29 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: Q > K, Q< K
- Replies: 25
- Views: 846
Re: Q > K, Q< K
K is the equilibrium constant and is present at equilibrium. However, when solving for Q, it can be happening at any point, hence why it can be greater, less, or equal to K. If it is less or greater than K then you know it is NOT at equilibrium yet. Hope this helps!
- Sun Jan 17, 2021 1:25 pm
- Forum: Ideal Gases
- Topic: Inverse Kc [ENDORSED]
- Replies: 41
- Views: 2187
Re: Inverse Kc [ENDORSED]
How I like to think about it is that if it is aA+bB<---->cC+dD then it is Kc, if it is cC+dD<---->aA+bB then it is 1/Kc (this is the inverse). Hope this helps!
- Sun Jan 17, 2021 12:46 pm
- Forum: Properties & Structures of Inorganic & Organic Acids
- Topic: Kw usage
- Replies: 6
- Views: 397
Re: Kw usage
I believe that if the temperature is not 25 degrees Celsius then the Kw is not 10^-14. Hope this helps!
- Sun Jan 17, 2021 12:43 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: quadratic equations to solve for X
- Replies: 7
- Views: 421
Re: quadratic equations to solve for X
How I like to think about it if when plugging in the two positive x concentrations into the actual concentration of a molecule, if it is negative then that does not make sense and therefore you will be needing to use the one that makes a positive concentration since concentration cannot be negative....
- Sun Jan 17, 2021 12:41 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Using the ICE table
- Replies: 36
- Views: 1442
Re: Using the ICE table
Using ICE tables are applicable to both partial pressures and concentrations as you use Kp and Kc the same way([products]/[reactions]). Hope this helps!
- Fri Jan 08, 2021 11:55 am
- Forum: Administrative Questions and Class Announcements
- Topic: Chemistry Community Quota
- Replies: 16
- Views: 1125
Re: Chemistry Community Quota
I feel as though the TAs will be looking for posts made in 2021 so that it is fair throughout the class! Hope this helps.
- Fri Jan 08, 2021 11:54 am
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: ICE tables
- Replies: 11
- Views: 559
Re: ICE tables
Is an ICE table to only way to solve questions when missing one of the concentration values?
- Fri Jan 08, 2021 11:52 am
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Pure Water
- Replies: 2
- Views: 157
Re: Pure Water
Yes, I did some research and found that the K value of pure water at 25*C is 1x10^-14! Hope this helps.
- Fri Jan 08, 2021 11:49 am
- Forum: Ideal Gases
- Topic: Units of Temperature
- Replies: 82
- Views: 3825
Re: Units of Temperature
You will always be using Kelvin since when looking at the other units in PV=nRT, there is only kelvin being used, so if using celsius for example, the units will not cancel out. Hope this helps!
- Fri Jan 08, 2021 11:46 am
- Forum: Ideal Gases
- Topic: PV=nRT and concentration
- Replies: 27
- Views: 1612
Re: PV=nRT and concentration
Molarity is given by doing (mol/volume). n is the number of moles, while V stands for volume so by doing n/V, it gives molarity, which is equivalent to the concentration(why we include molarity inside [] not only moles! Hope this helps!
- Tue Dec 08, 2020 5:26 pm
- Forum: Interionic and Intermolecular Forces (Ion-Ion, Ion-Dipole, Dipole-Dipole, Dipole-Induced Dipole, Dispersion/Induced Dipole-Induced Dipole/London Forces, Hydrogen Bonding)
- Topic: hydrogen bonding and melting points
- Replies: 3
- Views: 250
Re: hydrogen bonding and melting points
H-bonding is a type of intermolecular force and is the strongest intermolecular force out of D-D and LDF, therefore when a molecule is present in water(ie. intermolecular forces are between two molecules), it is the hardest to break, and therefore has a higher boiling point. Hope this helps!
- Tue Dec 08, 2020 5:22 pm
- Forum: Properties & Structures of Inorganic & Organic Bases
- Topic: Oxides
- Replies: 3
- Views: 296
Re: Oxides
O2- is a very strongly basic anion due to its very small size and high charge. Hope this helps!
- Tue Dec 08, 2020 5:11 pm
- Forum: Hybridization
- Topic: Lone pairs and multiple bonds
- Replies: 3
- Views: 322
Re: Lone pairs and multiple bonds
Yes, I just think that a pair of electrons, a single bond, double bond, and triple bond are each just ONE region of electron density.
- Sun Dec 06, 2020 10:19 pm
- Forum: Hybridization
- Topic: Focus 2 Exercise 45
- Replies: 2
- Views: 219
Re: Focus 2 Exercise 45
I drew out the different orbitals to help me with this problem! Hope this helps!
- Sun Dec 06, 2020 10:17 pm
- Forum: Hybridization
- Topic: Focus Question 2.45
- Replies: 3
- Views: 267
Re: Focus Question 2.45
I drew out the different orbitals to help me with this problem! Hope this helps (sorry that it is a little messy)
- Sun Dec 06, 2020 8:00 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Textbook Problem 2E.21) d.
- Replies: 3
- Views: 132
Textbook Problem 2E.21) d.
N2H4 makes the trigonal pyramidal shape, which should have an angle of <109.5 degrees, however in the answer key, it says that the angle is 107 degrees. How should we know the exact degrees for this molecule? Thank you!
- Wed Dec 02, 2020 10:49 am
- Forum: Naming
- Topic: Memorizing ligand names
- Replies: 6
- Views: 313
Re: Memorizing ligand names
I just had the discussion section and I think my TA said something similar to Table 9C.1 would be provided(which gives common ligands and their formulas). Please correct me if I'm wrong. Hope this helps!
- Wed Dec 02, 2020 10:40 am
- Forum: Student Social/Study Group
- Topic: Final Exam Study Tips
- Replies: 48
- Views: 2543
Re: Final Exam Study Tips
Do the TEXTBOOK problems, especially since Dr, Lavelle wrote that in the document with the description about the final.
- Wed Dec 02, 2020 10:37 am
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Oxidation Numbers
- Replies: 3
- Views: 125
Re: Oxidation Numbers
Yes, so the charge of the total oxygen atoms would be -8 since there are 4 oxygens, each with a -2 charge. Hope this helps!
- Tue Dec 01, 2020 5:26 pm
- Forum: Coordinate Covalent Bonds
- Topic: Polydentate Ligands
- Replies: 8
- Views: 498
Re: Polydentate Ligands
This helped me a lot to understand the differences between the types of ligands. Hope this helps!
- Tue Dec 01, 2020 5:21 pm
- Forum: Naming
- Topic: Ferrate vs iron
- Replies: 5
- Views: 259
Re: Ferrate vs iron
I think we use ferrate for coordination compounds. Hope that helps!
- Thu Nov 26, 2020 10:36 am
- Forum: Resonance Structures
- Topic: Resonance
- Replies: 9
- Views: 645
Re: Resonance
How I like to think about it is if it is an odd number of bonds attached to the central atom (ex. 3) and the central atom can have a full octet, then usually it has resonance. Resonance in terms of the bond strength is the average of the different identical ways of making the lewis structure. Hope t...
- Thu Nov 26, 2020 10:32 am
- Forum: Lewis Structures
- Topic: Most Stable Structure
- Replies: 23
- Views: 3609
Re: Most Stable Structure
To add to the posts above, a triple bond is more stable than a double, and then a double bond is more stable than a single bond. Hope this helps!
- Thu Nov 26, 2020 10:30 am
- Forum: Electronegativity
- Topic: How is electronegativity calculated?
- Replies: 4
- Views: 298
Re: How is electronegativity calculated?
Yes, I also agree that Dr. Lavelle does not expect us to know how to calculate EN. Just know the trends of EN! Hope this helps.
- Thu Nov 26, 2020 10:28 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: H2O VSEPR
- Replies: 27
- Views: 1327
Re: H2O VSEPR
H2O has an AX2E general formula, which is a bent shape! Hope that helps.
- Fri Nov 20, 2020 10:48 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: LiCO3 missing parts
- Replies: 2
- Views: 136
Re: LiCO3 missing parts
I think since it is Li^+ and O^2-, I would assume it comes from the oxygen since the overall charge of Li2CO3 is zero! Hope that helps.
- Fri Nov 20, 2020 10:43 am
- Forum: Bond Lengths & Energies
- Topic: 2D #13a
- Replies: 3
- Views: 124
Re: 2D #13a
When doing this problem, the biggest thing to remember is how in CO3^2- it has resonance meaning the double bond and 2 single bonds average out, making it still longer than the CO2 and CO! Which makes it easier to understand how to rank the molecules. Hope that helps!
- Fri Nov 20, 2020 10:38 am
- Forum: *Liquid Structure (Viscosity, Surface Tension, Liquid Crystals, Ionic Liquids)
- Topic: Boiling and Melting point
- Replies: 24
- Views: 3037
Re: Boiling and Melting point
Yes! How I like to think about it is that the molecules that have higher BP and MP are "stronger"(they can withstand dramatic temperatures) than molecules that have lower BP and MP. Hope that helps!
- Fri Nov 20, 2020 10:34 am
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Exercise 2A.15 a
- Replies: 4
- Views: 359
Re: Exercise 2A.15 a
I also agree that that is correct! Also, I like to look at the periodic table and know that for that column, the charge is 2-, because then it gets to that full octet! Hope that helps.
- Fri Nov 20, 2020 10:29 am
- Forum: Interionic and Intermolecular Forces (Ion-Ion, Ion-Dipole, Dipole-Dipole, Dipole-Induced Dipole, Dispersion/Induced Dipole-Induced Dipole/London Forces, Hydrogen Bonding)
- Topic: hydrogen bonding
- Replies: 7
- Views: 390
Re: hydrogen bonding
Also remember that Hydrogen bonding is a type of intermolecular force, which means that if it is given only one molecule, you have to assume that it H-bonds with another identical molecule, so now there are two identical molecules in play! Hope that helps!
- Sun Nov 15, 2020 5:42 pm
- Forum: Lewis Structures
- Topic: Textbook Problem 2D.3
- Replies: 2
- Views: 166
Textbook Problem 2D.3
How come Ba-Br has a greater EN difference than Be-Br? Since EN increases when going up the periodic table, I am thinking that Be has a greater EN and therefore a bigger EN difference between Be-Br, but that is incorrect since the textbook says that the EN difference is greater for Ba-Br.
- Sat Nov 14, 2020 5:47 pm
- Forum: Ionic & Covalent Bonds
- Topic: 2A.15
- Replies: 3
- Views: 221
Re: 2A.15
Yes, that looks correct. Since losing three electrons is easier than gaining 5, it seems as though it will be Ga+3. Hope this helps!
- Sat Nov 14, 2020 5:44 pm
- Forum: Ionic & Covalent Bonds
- Topic: Textbook 2A #9
- Replies: 3
- Views: 208
Re: Textbook 2A #9
So the M2+ ions (where M is a metal) makes it very simple to find since you take away from the 4s2, however when it is M3+ ions (where M is a metal), you have to take away 4s2 and 3d1. Hope this helps!
- Sat Nov 14, 2020 5:42 pm
- Forum: Dipole Moments
- Topic: Boiling/Melting Points
- Replies: 15
- Views: 1301
Re: Boiling/Melting Points
When looking at boiling points or melting points, you want to be using INTERmolecular forces NOT INTRAmolecular forces. This helped me a lot when figuring out how to solve this type of problem. Hope this helps!
- Sat Nov 14, 2020 5:39 pm
- Forum: Lewis Structures
- Topic: Drawing Lewis Structures on Midterm
- Replies: 31
- Views: 1228
Re: Drawing Lewis Structures on Midterm
Yes, since when drawing the lewis structures, the most accurate ones are the ones that are the most stable. The closes to zero the lewis structure are the more stable it is! Hope this helps!
- Sun Nov 08, 2020 11:53 am
- Forum: Lewis Structures
- Topic: question about BCl3
- Replies: 2
- Views: 138
question about BCl3
How come in the molecule, BCl3, boron does not follow the octet rule(ie. it has 6 shared electrons, not 8). I thought the only exceptions are H, He, Li, and Be. Thanks!
- Sat Nov 07, 2020 6:00 pm
- Forum: Octet Exceptions
- Topic: Octet Exception for H, He, Li, and Be
- Replies: 5
- Views: 179
Re: Octet Exception for H, He, Li, and Be
Yes, your reasoning is correct because they can only hold a maximum of two electrons in its valence level, which defies the octet rule! Hope this helps.
- Sat Nov 07, 2020 5:51 pm
- Forum: Lewis Structures
- Topic: Negative Sign
- Replies: 12
- Views: 881
Re: Negative Sign
When finding the charge of the lewis dot structure, I first find the charge of each individual atom and then add up the charges to find the total charge! Hope this helps.
- Sat Nov 07, 2020 5:49 pm
- Forum: Ionic & Covalent Bonds
- Topic: Salts v. Ionic bonds
- Replies: 9
- Views: 330
Re: Salts v. Ionic bonds
Since this is general chemistry, I believe that most ionic compounds that will be given to us include Na+. And the reason Na+ makes an ionic compound is since the bonds formed between two ions of opposite charge makes it an ionic compound. Hope this helps!
- Sat Nov 07, 2020 5:43 pm
- Forum: Resonance Structures
- Topic: Separate and Identifiable Bonds
- Replies: 2
- Views: 122
Re: Separate and Identifiable Bonds
I think molecules with multiple resonance structures will be more stable than one with fewer resonance structures and some resonance structures contribute more to the stability of the molecule than others (ie. formal charges aid in determining this). So you are correct! Hope this helps.
- Sat Nov 07, 2020 5:39 pm
- Forum: Resonance Structures
- Topic: Oxidation Number
- Replies: 9
- Views: 319
Re: Oxidation Number
The oxidation number of a free element is always 0 and the oxidation number of a monatomic ion equals the charge of the ion, which is found in the periodic table.
- Sat Oct 31, 2020 5:44 pm
- Forum: Lewis Structures
- Topic: Drawing Lewis Structures
- Replies: 7
- Views: 587
Re: Drawing Lewis Structures
I don't think we need to know the difference between a ring and a chain bc that is more organic chemistry.
- Sat Oct 31, 2020 5:41 pm
- Forum: DeBroglie Equation
- Topic: Diffraction Pattern
- Replies: 9
- Views: 439
Re: Diffraction Pattern
^^^ yes I believe so since diffraction patterns are caused by waves! Hope this helps.
- Sat Oct 31, 2020 5:32 pm
- Forum: Trends in The Periodic Table
- Topic: Oxygen and Ionization Energy
- Replies: 9
- Views: 557
Re: Oxygen and Ionization Energy
I was going to ask this question on chemistry community too! All I know is that oxygen has lower ionization energy than fluorine, as fluorine is farther to the right on the periodic table and follows the trend that IE increases as you go right. However, the anomaly is that oxygen has lower ionizatio...
- Sat Oct 31, 2020 5:23 pm
- Forum: Trends in The Periodic Table
- Topic: Atomic Radius
- Replies: 3
- Views: 132
Re: Atomic Radius
This diagram helps me understand the trends in the periodic table and how they interplay with each other! Hope this helps!
- Sat Oct 31, 2020 5:20 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Excited Electron States
- Replies: 2
- Views: 159
Re: Excited Electron States
Yes, that is what I also got from the lectures. It makes sense because if you see that electrons have been "moved" to a higher orbital before filling the lower orbital, then that atom is in an excited state, which would be different than the ground-state electron configuration.
- Sat Oct 31, 2020 5:16 pm
- Forum: Properties of Electrons
- Topic: Sapling #28
- Replies: 4
- Views: 181
Re: Sapling #28
I ended with phosphorous too! So I think it is the correct reasoning!
- Sat Oct 24, 2020 11:45 am
- Forum: Heisenberg Indeterminacy (Uncertainty) Equation
- Topic: Showing our Work on the Midterm
- Replies: 10
- Views: 465
Re: Showing our Work on the Midterm
We use the periodic table that Dr. Lavelle provides us on his website! It is next to the equation sheet that is also going to be used in the midterm! Hope this helps.
- Fri Oct 23, 2020 7:13 pm
- Forum: Properties of Light
- Topic: Wavelength
- Replies: 14
- Views: 619
Re: Wavelength
I usually do nm, but it all depends on what the problem is asking you to convert to. I look at the word problem and also what unit the multiple-choice options are in! Hope this helps!
- Fri Oct 23, 2020 7:08 pm
- Forum: Heisenberg Indeterminacy (Uncertainty) Equation
- Topic: clarification: Δx
- Replies: 6
- Views: 262
Re: clarification: Δx
How I like to think about it is if the uncertainty is 10Å, then it is just 10 x10^-10 m, while if it gives you +/-10Å, it will be 10x10^-10 m in the positive direction and 10x10^-10 m in the negative direction as the uncertainty. Hope this helps!
- Fri Oct 23, 2020 6:59 pm
- Forum: Heisenberg Indeterminacy (Uncertainty) Equation
- Topic: Logic behind it
- Replies: 3
- Views: 220
Re: Logic behind it
Yes, I noticed that problem too in the module. In the lecture, there was a problem where something was greater than the speed of light(which is impossible) and it was clearly stated that this isn't logical. So I would definitely use logic over the answer you get! Hope this helps.
- Fri Oct 23, 2020 6:54 pm
- Forum: Heisenberg Indeterminacy (Uncertainty) Equation
- Topic: delta V
- Replies: 4
- Views: 226
Re: delta V
I was confused by that too! So you multiply it by 2 so that it can be within the entire spectrum of uncertainty, which accounts for the positive or negative uncertainty?
- Sun Oct 18, 2020 4:39 pm
- Forum: Properties of Electrons
- Topic: Wave Properties of Electrons
- Replies: 6
- Views: 321
Re: Wave Properties of Electrons
They were surprised that this diffraction pattern of the waves worked on a substance like crystal(ie. table salt) and what was flowing like a wave was the photons.
- Sun Oct 18, 2020 4:31 pm
- Forum: Einstein Equation
- Topic: workshop wk2question
- Replies: 2
- Views: 152
workshop wk2question
T/F, An increase in intensity means an increase in energy?
I am not sure what the answer to this is.
I am not sure what the answer to this is.
- Sun Oct 18, 2020 4:10 pm
- Forum: Properties of Light
- Topic: Study Advice
- Replies: 50
- Views: 2330
Re: Study Advice
I think there will be a step up session that will have a practice midterm. That's all I know so far though :/
- Sun Oct 18, 2020 4:08 pm
- Forum: Properties of Light
- Topic: Question regarding webcam
- Replies: 8
- Views: 417
Re: Question regarding webcam
My phone and Ipad worked well for this! Hope this helps!
- Sun Oct 18, 2020 4:07 pm
- Forum: Properties of Light
- Topic: Electron diffraction
- Replies: 5
- Views: 249
Re: Electron diffraction
To answer the multiple-choice question, the answer is electron diffraction (B). During Friday's lecture, Dr. Lavelle showed us that electrons have wave properties by visualizing the two types of diffraction patterns, constructive (waves in-phase) and destructive interference (waves out of phase). Th...
- Thu Oct 15, 2020 9:53 pm
- Forum: Properties of Light
- Topic: Balmer vs Lyman
- Replies: 12
- Views: 491
Re: Balmer vs Lyman
In the diagram that I posted above, it shows how the Balmer series is in the infrared region, while the Laymen series is in the UV region. The infrared region has less energy as it has a longer wavelength then the UV region which has a shorter wavelength and thus making it have a higher energy. This...
- Thu Oct 15, 2020 11:05 am
- Forum: Properties of Light
- Topic: Balmer vs Lyman
- Replies: 12
- Views: 491
Re: Balmer vs Lyman
Hi, here is a diagram Dr. Lavelle showed us in his lecture on Wednesday. This really helped me understand how the energy levels relate to the two different types of series.
- Thu Oct 15, 2020 11:02 am
- Forum: Properties of Light
- Topic: Sun Spectrum
- Replies: 3
- Views: 174
Re: Sun Spectrum
I think most of the Sun's light is in the infrared, visible, and ultraviolet parts of the electromagnetic spectrum but it emits shorter wavelengths like UV rays.