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by Reese_Gover2K
Wed Dec 16, 2020 3:31 pm
Forum: General Science Questions
Topic: Grades
Replies: 22
Views: 286

Re: Grades

You can check CCLE or myUCLA but I have been told by professors and TA's in other classes that the myUCLA gradebook, which you can access by clicking on the classes tab and then exam/homework grades, is the more reputable source.
by Reese_Gover2K
Wed Dec 16, 2020 3:25 pm
Forum: General Science Questions
Topic: Passing Grade
Replies: 34
Views: 231

Re: Passing Grade

I originally thought that it meant 50% of Chem community and homework but if what everyone else is saying is true, which I think it is as somebody said their TA confirmed it, then it should just be a 50% overall.
by Reese_Gover2K
Wed Dec 16, 2020 3:23 pm
Forum: Administrative Questions and Class Announcements
Topic: Chem community points
Replies: 16
Views: 118

Re: Chem community points

They haven't counted everyone's posts yet because Professor Lavelle extended the deadline so it should be in once the deadlines over or by the latest Saturday as Professor Lavelle said he'd hopefully have grades finalized by Saturday.
by Reese_Gover2K
Wed Dec 16, 2020 3:21 pm
Forum: Properties & Structures of Inorganic & Organic Acids
Topic: Why isn't HF a strong acid?
Replies: 23
Views: 138

Re: Why isn't HF a strong acid?

It's because since F is such a small atom the bond length would be much smaller between H and F than between H and Cl so since HF has just a small enough bond length it would not be an acid.
by Reese_Gover2K
Wed Dec 16, 2020 3:19 pm
Forum: Properties & Structures of Inorganic & Organic Acids
Topic: Week 10 Sapling Q10
Replies: 5
Views: 47

Re: Week 10 Sapling Q10

Ca(OH)2 would be the stronger base because it would produce more OH- ions.
by Reese_Gover2K
Sun Dec 06, 2020 11:23 am
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Oxidation Number
Replies: 4
Views: 48

Re: Oxidation Number

HilaGelfer_3I wrote:Hi
I found this sapling link with oxidation number rules really helpful!
https://sites.google.com/site/chempendix/oxidation

This looks super helpful thanks for sharing!
by Reese_Gover2K
Sun Dec 06, 2020 11:22 am
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Sapling Week 9 #4
Replies: 5
Views: 44

Re: Sapling Week 9 #4

I think ligands are like a subset of a Lewis base as they act a similar way but ligands are more specific than Lewis bases. I've been thinking about it like: All ligands are Lewis bases but not all Lewis bases are ligands.
by Reese_Gover2K
Sun Dec 06, 2020 11:19 am
Forum: Naming
Topic: Order of Ligands/naming
Replies: 28
Views: 138

Re: Order of Ligands/naming

As everyone else is saying, put the ligands in alphabetical order (excluding prefixes) and then add the transition metal at the end.
by Reese_Gover2K
Sun Dec 06, 2020 11:17 am
Forum: Naming
Topic: Helpful Videos for Naming
Replies: 22
Views: 123

Re: Helpful Videos for Naming

Thank you so much! This is something I'm having a hard time memorizing so I'll be sure to check those out!
by Reese_Gover2K
Sun Dec 06, 2020 11:16 am
Forum: Naming
Topic: Correct name for Na[Co(NH3)3Cl3]?
Replies: 8
Views: 6463

Re: Correct name for Na[Co(NH3)3Cl3]?

darchen3G wrote:This is a question from many years ago...

But yes the coordination compound itself is Triamminetrichlorocobaltate (II) and the name of the entire compound is Sodium Triamminetrichlorocobaltate (II)


Thanks! This really helped me understand why that's the answer.
by Reese_Gover2K
Sun Nov 29, 2020 12:03 pm
Forum: Hybridization
Topic: sapling #11
Replies: 11
Views: 64

Re: sapling #11

So finding hybridization is just finding the # of regions of electron density. For example, if a Carbon is bound to 3 Hydrogens and has a lone pair, it has 4 regions of electron density which corresponds to an sp3 orbital. Here's a list of the number of regions and what hybridization they correspond...
by Reese_Gover2K
Sun Nov 29, 2020 11:59 am
Forum: Hybridization
Topic: Multiple Bonds with Hybridization
Replies: 6
Views: 27

Re: Multiple Bonds with Hybridization

Like everyone else is saying hybridization is affected by regions of electron density. A double bond or a triple bond are both considered one region of density just like a single bond is. Hope this helps :)
by Reese_Gover2K
Sun Nov 29, 2020 11:56 am
Forum: Hybridization
Topic: Sapling #12
Replies: 27
Views: 182

Re: Sapling #12

So finding the hybridization of the oxygen is, like everyone else is saying, the same idea as finding the hybridization of the carbon. So look at your structure and count all the regions of electron density that Oxygen has, and then pick the hybridization that matches that number of regions. Hope th...
by Reese_Gover2K
Sun Nov 29, 2020 11:53 am
Forum: Hybridization
Topic: sp and sp2
Replies: 7
Views: 59

Re: sp and sp2

So the hybridization corresponds to the # of regions of electron density. So an sp3 orbital has 4 regions of electron density, and sp2 has 3 regions, and an sp has 2 regions. Knowing what they look like is pretty much just knowing the shape. For example, an sp3 orbital has 4 regions of electron dens...
by Reese_Gover2K
Sun Nov 29, 2020 11:49 am
Forum: Hybridization
Topic: Lecture #23
Replies: 13
Views: 115

Re: Lecture #23

Yes some electrons are delocalized meaning that they are shared between the atoms
by Reese_Gover2K
Sun Nov 22, 2020 1:22 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Week 7 Sapling: #5
Replies: 4
Views: 26

Re: Week 7 Sapling: #5

Axial atoms are on the vertical axis of the atom and the equatorial atoms are on the horizontal axis of the atom. A way I remember these is that an equal sign is comprised of 2 horizontal lines and likewise equatorial atoms are on the horizontal axis of the atom and axial atoms are on the opposite a...
by Reese_Gover2K
Sun Nov 22, 2020 1:18 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Lone Pair E-
Replies: 47
Views: 263

Re: Lone Pair E-

Yes they do count as a region of electron density.
by Reese_Gover2K
Sun Nov 22, 2020 1:16 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Tips for memorizing different molecular shapes
Replies: 9
Views: 76

Re: Tips for memorizing different molecular shapes

Hi, I don't have any ways to memorize it yet myself, but I found this cool Youtube video that breaks it down and uses the an example of remembering it like a BLT sandwich. I hope that helps! https://www.youtube.com/watch?v=GnXSGR-UEDI&feature=emb_title Thank you so much! I am also having troubl...
by Reese_Gover2K
Sun Nov 22, 2020 1:10 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Sapling HW Smallest Bond Angle
Replies: 4
Views: 38

Re: Sapling HW Smallest Bond Angle

You can approximate by determining how many regions of electron density there are and how many lone pairs there are. From there you know that the bond angle is less than the bond angle of a typical molecule with that many regions of electron density and the more lone pairs the smaller/less than the ...
by Reese_Gover2K
Sun Nov 22, 2020 1:05 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Lecture 20 VSEPR
Replies: 6
Views: 29

Re: Lecture 20 VSEPR

You'd use the Lewis structure with the lone pair as the molecule SO3 has a charge of -2 and since S can have an extended octet the lone pair would be on the S.
by Reese_Gover2K
Sat Nov 14, 2020 5:49 pm
Forum: Formal Charge and Oxidation Numbers
Topic: Clarification
Replies: 8
Views: 37

Re: Clarification

Yes! The overall charge of a molecule is the sum of all the formal charges.
by Reese_Gover2K
Sat Nov 14, 2020 5:47 pm
Forum: Lewis Structures
Topic: Nitrite vs Nitrate
Replies: 17
Views: 141

Re: Nitrite vs Nitrate

The difference between Nitrite and Nitrate is the number of Oxygen atoms they have. Nitrate=NO3 and Nitrite=NO2 both have a charge of -1. I don't know for sure whether we'll need it memorized, but he hasn't said we need to memorize it so I don't believe we do.
by Reese_Gover2K
Sat Nov 14, 2020 5:42 pm
Forum: Ionic & Covalent Bonds
Topic: Sapling HW Question 13
Replies: 3
Views: 32

Re: Sapling HW Question 13

So since a Hydrogen bond occurs between Hydrogen and N, O, and F we can look for these atoms in the molecule. Since Oxygen has 2 lone pairs meaning that it can form 2 Hydrogen bonds, and there are 2 Nitrogens each with 1 lone pair that is 2 Hydrogen bonds, and lastly there are 4 Hydrogen atoms that ...
by Reese_Gover2K
Sat Nov 14, 2020 5:37 pm
Forum: Ionic & Covalent Bonds
Topic: Sapling Hw Urea Question
Replies: 2
Views: 30

Re: Sapling Hw Urea Question

The number is 8 because, since Hydrogen bonds occur with N,O, and F atoms, the Oxygen can bond with 2 water molecules, the 4 Hydrogens can each bond with one water molecule, and each Nitrogen can bond with one molecule so if you add up all of those bonds you get 8.
by Reese_Gover2K
Sat Nov 14, 2020 5:32 pm
Forum: Ionic & Covalent Bonds
Topic: Metals and Nonmetals in p block
Replies: 3
Views: 32

Re: Metals and Nonmetals in p block

As the user above me said the line already exists on your table, but once the lockdown browser starts you can take a highlighter and emphasize the line.
by Reese_Gover2K
Sun Nov 08, 2020 11:40 am
Forum: Trends in The Periodic Table
Topic: Midterm 2 Study Group
Replies: 7
Views: 65

Re: Midterm 2 Study Group

This sounds great and will be super helpful! Also Thursday this week sounds good!
by Reese_Gover2K
Sun Nov 08, 2020 11:34 am
Forum: Administrative Questions and Class Announcements
Topic: Second Midterm Date
Replies: 9
Views: 73

Re: Second Midterm Date

It will be during your discussion during week 7 so you still have about 1-1.5 weeks to study depending on when your discussion is.
by Reese_Gover2K
Sun Nov 08, 2020 11:32 am
Forum: Quantum Numbers and The H-Atom
Topic: when n=5 and l=4
Replies: 16
Views: 156

Re: when n=5 and l=4

When n=5 the general rule is that l=n-1 but that isn't always the case as l could potentially be 0,1,2,etc. For Sapling questions though, unless they give you a specific element, I would use the general rule for determination and l=4 corresponds to the letter g.
by Reese_Gover2K
Sun Nov 08, 2020 11:27 am
Forum: Trends in The Periodic Table
Topic: Sapling Question (Radius)
Replies: 10
Views: 65

Re: Sapling Question (Radius)

The C- would have the largest radius as it has an extra electron that repels the others therefore increasing the radius, then is C, and finally C+ because since it is missing an electron it has a smaller radius.
by Reese_Gover2K
Sun Nov 08, 2020 11:25 am
Forum: Electron Configurations for Multi-Electron Atoms
Topic: F orbitals?
Replies: 21
Views: 109

Re: F orbitals?

I believe Dr Lavelle said in lecture that we won't need to know f orbitals so don't worry to much about it :)
by Reese_Gover2K
Sun Nov 01, 2020 2:52 pm
Forum: Administrative Questions and Class Announcements
Topic: Midterm grades
Replies: 19
Views: 210

Re: Midterm grades

I don't know I had the same question. Someone else had a question about whether doctor Lavelle was curving the test or not and someone in the comments wrote that he wasn't but since he's offering partial credit on questions it's taking some time. Maybe ask your TA in discussion?
by Reese_Gover2K
Sun Nov 01, 2020 2:49 pm
Forum: Properties of Light
Topic: How to remember what v is in equations
Replies: 46
Views: 261

Re: How to remember what v is in equations

The best way is to look at how they are written velocity is a regular v and for frequency it is a swoopy kinda cursive like v which is the greek letter nu.
by Reese_Gover2K
Sun Nov 01, 2020 2:46 pm
Forum: Photoelectric Effect
Topic: Sapling Problem #6
Replies: 7
Views: 122

Re: Sapling Problem #6

Yea that's exactly it. The number of possible transitions is the number of spectral lines so 7->6 is a spectral line and 7->5 is another spectral line as so on until you reach 7->1 and get a total of 6 spectral lines.
by Reese_Gover2K
Sun Nov 01, 2020 2:40 pm
Forum: Photoelectric Effect
Topic: Sapling HW #11
Replies: 5
Views: 55

Re: Sapling HW #11

I had trouble with that same problem, my problem was forgetting to convert from nm to meters. But once you do that you just solve for the frequency and then input that into the equation v = R[1/n1^2 - 1/n2^2] with n1=2 and solve for n2.
by Reese_Gover2K
Sun Nov 01, 2020 2:35 pm
Forum: Photoelectric Effect
Topic: Sapling using de broglie's
Replies: 7
Views: 78

Re: Sapling using de broglie's

Your problem may come from the fact that molar mass is in g/mol and the problem gives you units of kg.
by Reese_Gover2K
Sun Oct 25, 2020 11:29 am
Forum: Einstein Equation
Topic: m vs nm
Replies: 66
Views: 454

Re: m vs nm

Dr Lavelle said in lecture that unless the question specifically specifies that your answer should be in nm then it is fine to leave it in meters.
by Reese_Gover2K
Sun Oct 25, 2020 11:26 am
Forum: Einstein Equation
Topic: Scratch paper during the exam
Replies: 19
Views: 153

Re: Scratch paper during the exam

It totally depends on your TA so I would shoot them an email asking whether or not that is fine, but I also think that as long as you show them that your piece of paper is blank on both sides and you aren't cheating you should be fine.
by Reese_Gover2K
Sun Oct 25, 2020 11:23 am
Forum: Heisenberg Indeterminacy (Uncertainty) Equation
Topic: When do we use Heisenberg indeterminacy equation
Replies: 10
Views: 70

Re: When do we use Heisenberg indeterminacy equation

I think that it will mostly be in problems like the ones we did in class or theoretical questions, also I think the big give away for when the use Heisenberg's equation is that they give the radius and uncertainty in the problem which is different than in DeBroglie's where all it gives is mass, velo...
by Reese_Gover2K
Sun Oct 25, 2020 11:20 am
Forum: Heisenberg Indeterminacy (Uncertainty) Equation
Topic: Question about the Delta X and what it stands for
Replies: 6
Views: 53

Re: Question about the Delta X and what it stands for

Delta x is in fact the uncertainty of position. So if the radius given is 6 and the uncertainty is +-1 then you would do the math (6-1=5, 6+1=7, 7-5=2) to get the uncertainty of position is 2. If they tell you the electron or particle is confined to the atom, the uncertainty of position would be the...
by Reese_Gover2K
Sun Oct 25, 2020 11:13 am
Forum: DeBroglie Equation
Topic: Purpose of DeBroglie Equation
Replies: 11
Views: 114

Re: Purpose of DeBroglie Equation

The DeBroglie Equation was in fact meant to suggest that an object with a very small mass has wavelike properties that we can identify. It has to be a very small mass because since mass is on the bottom, the bigger the mass the smaller the wavelength and the less detectable it is. What you wrote sho...
by Reese_Gover2K
Sun Oct 18, 2020 1:02 pm
Forum: Einstein Equation
Topic: E=hv vs E=pc?
Replies: 8
Views: 325

Re: E=hv vs E=pc?

Yep you got it! They both calculate the same thing but the one you use depends on the information you're given. You'd use E=pc if you're given the momentum of the photon and you'd use E=hv if you're given the frequency.
by Reese_Gover2K
Sun Oct 18, 2020 12:55 pm
Forum: Properties of Light
Topic: Frequency vs Wavelength
Replies: 22
Views: 141

Re: Frequency vs Wavelength

Like everyone else is saying Wavelength and Frequency are inversely related. When you have a greater frequency it results in a shorter wavelength and vice versa. The frequency also determines what kind of wave it is. Higher frequency=higher energy and lower frequency=lower energy.
by Reese_Gover2K
Sun Oct 18, 2020 12:53 pm
Forum: Properties of Light
Topic: Speed of Light Equation
Replies: 6
Views: 48

Re: Speed of Light Equation

I believe that, like in most science, we will use the speed of light in a vacuum but I can't be positive. Either way though I believe constants like the speed of light will be given to us for tests as Dr Lavelle said in his lecture that we would always be given constants we just have to know which o...
by Reese_Gover2K
Sun Oct 18, 2020 12:44 pm
Forum: Student Social/Study Group
Topic: How are you studying?
Replies: 203
Views: 1291

Re: How are you studying?

I've been taking notes throughout the lecture and highlighting key terms/vocab/important concepts. Then I read through my notes and then if there's any info I feel I'm missing I watch that part of the lecture again to see if it's been answered, and if not I write my questions to either post here or ...
by Reese_Gover2K
Sun Oct 18, 2020 12:41 pm
Forum: Einstein Equation
Topic: What are the units for E
Replies: 16
Views: 124

Re: What are the units for E

Since E is energy the units should be Joules.
by Reese_Gover2K
Sat Oct 10, 2020 2:29 pm
Forum: Balancing Chemical Reactions
Topic: Order of Balancing Rxns
Replies: 23
Views: 115

Re: Order of Balancing Rxnx

I typically rewrite the equation with blank spaces in front of each reactant/product and then make a chart counting the number of each element. Then I look at which element would be easiest to balance first and start with that one. And then whenever I write a new coefficient in the equation I alter ...
by Reese_Gover2K
Sat Oct 10, 2020 2:18 pm
Forum: Significant Figures
Topic: How many significant figures are in 7.00 x 10^2?
Replies: 25
Views: 589

Re: How many significant figures are in 7.00 x 10^2?

Since 7.00 x 10^2 would become 700. and not just 700 there would be a decimal at the end making those zeros sig figs and therefore 7.00 x 10^2 has 3 sig figs.
by Reese_Gover2K
Sat Oct 10, 2020 2:15 pm
Forum: Significant Figures
Topic: How to deal with significant figures in decimals with zeros.
Replies: 20
Views: 194

Re: How to deal with significant figures in decimals with zeros.

There's a rhyme my high school chem teacher taught us to remember this. If there's a decimal preceding that end 0 has meaning and if there are nonzeros on each side, that 0 must reside. So in the case of 20.01 since there is a decimal preceding the zero that zero is a sig fig and since there are non...
by Reese_Gover2K
Sat Oct 10, 2020 2:10 pm
Forum: Limiting Reactant Calculations
Topic: #10 Week 1 HW
Replies: 8
Views: 92

Re: #10 Week 1 HW

Yea d is for density and in this case it would be in grams/mL.
by Reese_Gover2K
Sat Oct 10, 2020 2:07 pm
Forum: Limiting Reactant Calculations
Topic: Last Question on the Sapling Hw (Week 1)?
Replies: 12
Views: 156

Re: Last Question on the Sapling Hw (Week 1)?

So first you need to convert the 0.50mL to grams so that you can use the molar mass to figure out how many moles you have of 2-butanone. And since there is a one to one ratio of 2-butanone and 3-methyl-3-hexanol, however many mols you have of 2-butanone is the number of mols you have of 3-methyl-3-h...

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