Search found 51 matches
- Thu Dec 17, 2020 2:38 am
- Forum: General Science Questions
- Topic: Passing Grade
- Replies: 34
- Views: 1855
Re: Passing Grade
50% of ALL points. Check out the syllabus & good luck!
- Thu Dec 17, 2020 2:37 am
- Forum: Properties of Light
- Topic: Wavelength
- Replies: 26
- Views: 1204
Re: Wavelength
Determining spectrum would be a good example of nm, but I'm sure in experimentation it isn't hard to switch between the two at all.
- Thu Dec 17, 2020 2:36 am
- Forum: Sigma & Pi Bonds
- Topic: Bond length [ENDORSED]
- Replies: 13
- Views: 788
Re: Bond length [ENDORSED]
We use VESPR theory and our knowledge of different compounds and their bond lengths, but I've only ever heard of it being done with a computer.
- Thu Dec 17, 2020 2:35 am
- Forum: Properties of Electrons
- Topic: Difference between electrons and light properties
- Replies: 5
- Views: 677
Re: Difference between electrons and light properties
Well for one, electrons are charged. They behave totally differently. A photon is more energy condensed, while an electron is a charge. I'm not good enough at quantum physics to go further.
- Thu Dec 17, 2020 2:34 am
- Forum: Naming
- Topic: Naming Coordination Complexes
- Replies: 4
- Views: 380
Re: Naming Coordination Complexes
I start grouping things into my head, and making mental connections. E.g. this one ligand corresponds to this name, and then coming up with a quirky way or connection to it. I've caught myself singing to memorize before. It's hard though, best of luck.
- Thu Dec 17, 2020 2:33 am
- Forum: Student Social/Study Group
- Topic: Plans for Relaxing After Finals
- Replies: 98
- Views: 11406
Re: Plans for Relaxing After Finals
What a sweet post! I plan to use up my swipes and enjoy my time at UCLA before I have to go home.
- Thu Dec 17, 2020 2:32 am
- Forum: Lewis Acids & Bases
- Topic: Lewis vs Bronsted
- Replies: 20
- Views: 1062
Re: Lewis vs Bronsted
Think of it like an umbrella - Lewis bases' definition, using lone pairs, encompass more than the smaller umbrella of Bronsted.
- Thu Dec 17, 2020 2:31 am
- Forum: Properties & Structures of Inorganic & Organic Acids
- Topic: Organic vs Inorganic
- Replies: 5
- Views: 525
Re: Organic vs Inorganic
Organic chemistry is the chemistry of carbons, so yes!
- Thu Dec 17, 2020 2:30 am
- Forum: Photoelectric Effect
- Topic: Decimals
- Replies: 11
- Views: 644
Re: Decimals
I do four, but you're really thinking about significant figures here, which change based on the problem text.
- Thu Dec 17, 2020 2:30 am
- Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
- Topic: Calculating H+
- Replies: 17
- Views: 827
Re: Calculating H+
You're essentially going backwards. Initially you take the negative log, so do the opposite. From there, you'll have your pKa and can move forward accordingly.
- Thu Dec 17, 2020 2:29 am
- Forum: Amphoteric Compounds
- Topic: More likely acid or base
- Replies: 4
- Views: 399
Re: More likely acid or base
Yep! Depending on what H2O is around, it might act as an acid or a base. I imagine that this applies to the environment around it on a greater scale.
- Thu Dec 17, 2020 2:28 am
- Forum: Sigma & Pi Bonds
- Topic: Pi Bonds
- Replies: 18
- Views: 751
Re: Pi Bonds
Pi bonds by nature can only apply to covalent bonds. Ionic bonds don't engage in sigma or pi bonds.
- Thu Dec 17, 2020 2:27 am
- Forum: Ionic & Covalent Bonds
- Topic: Ionic vs Covalent Bonds
- Replies: 9
- Views: 578
Re: Ionic vs Covalent Bonds
As others have said, compare electronegativity, but I find that it helps to recognize that salts and metals will almost always be ionic.
- Thu Dec 17, 2020 2:26 am
- Forum: Polyprotic Acids & Bases
- Topic: Defintion
- Replies: 39
- Views: 2336
Re: Defintion
Something is polyprotic when there are multiple protons (H) available to be deprotonated.
- Thu Dec 17, 2020 2:26 am
- Forum: Properties & Structures of Inorganic & Organic Acids
- Topic: Stronger acids and stability?
- Replies: 5
- Views: 2151
Re: Stronger acids and stability?
Stronger acids aren't stable, as they're likely to act as an acid and react. However, their conjugate bases are rather stable.
- Thu Dec 17, 2020 2:24 am
- Forum: Properties & Structures of Inorganic & Organic Acids
- Topic: Why isn't HF a strong acid?
- Replies: 23
- Views: 7129
Re: Why isn't HF a strong acid?
HF doesn't want to disassociate. The electronegativity is different enough that they're basically stuck to one another, and won't act as a strong acid.
- Thu Dec 17, 2020 2:23 am
- Forum: SI Units, Unit Conversions
- Topic: Avogadro's Number
- Replies: 12
- Views: 2149
Re: Avogadro's Number
The roadmap we've seen in stereochemistry explains the use of Avogadro's number. From going from moles to atoms or vice versa, Avogadro's number is the way to go.
- Thu Dec 17, 2020 2:22 am
- Forum: *Titrations & Titration Calculations
- Topic: Polyprotic Acids and Bases
- Replies: 4
- Views: 3134
Re: Polyprotic Acids and Bases
A polyprotic compound has multiple places where it can be deprotonated. The Hs can be taken off, and there are multiple of them.
- Thu Dec 17, 2020 2:21 am
- Forum: Identifying Acidic & Basic Salts
- Topic: Determining Acids or Bases (Number based)
- Replies: 3
- Views: 458
Re: Determining Acids or Bases (Number based)
Below a pH of 7 is acidic, and above it is basic. I find using the pKa to find pH to be the easiest way to figure out if something is acidic or basic for sure.
- Thu Dec 17, 2020 2:20 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Seesaw vs. trigonal pyramidal
- Replies: 22
- Views: 2248
Re: Seesaw vs. trigonal pyramidal
They aren't the same! One refers to a # of 5, the other to a 4. Others have explained shape!
- Thu Dec 17, 2020 2:19 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: wedge and dash
- Replies: 14
- Views: 2563
Re: wedge and dash
If you're staring straight at it, a wedge is away from you and a dash is towards you. Sometimes you'll see a combined notation referring to the bond being either in different conformations.
- Thu Dec 17, 2020 2:18 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Tetrahedral molecular shape
- Replies: 10
- Views: 1728
Re: Tetrahedral molecular shape
A tetrahedral shape doesn't really fill in a sphere. There's no need for it to add up to 360 degrees.
- Thu Dec 17, 2020 2:17 am
- Forum: Hybridization
- Topic: Hybridization of 2p and 2p2
- Replies: 2
- Views: 278
Re: Hybridization of 2p and 2p2
I believe it refers to the orbitals being filled with two electrons.
- Thu Dec 17, 2020 2:16 am
- Forum: Ideal Gases
- Topic: Reading the textbook
- Replies: 262
- Views: 146855
Re: Reading the textbook
Honestly not a huge fan of the textbook. I'll stick to rewatching portions of the lecture any day.
- Thu Dec 17, 2020 2:14 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: What are the bond angles for T shaped?
- Replies: 21
- Views: 8457
Re: What are the bond angles for T shaped?
Slightly less than 90 degrees.
- Thu Dec 17, 2020 2:13 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Bent vs Angular
- Replies: 20
- Views: 875
Re: Bent vs Angular
Bent and angular are the same as many others have said!
- Thu Dec 17, 2020 2:12 am
- Forum: Hybridization
- Topic: Hybridization
- Replies: 2
- Views: 210
Re: Hybridization
When there's only one s, yes. Otherwise, it fills in in order (e.g. sp2)
- Sun Nov 29, 2020 4:35 pm
- Forum: Hybridization
- Topic: Single Bonds and Sigma Bonds
- Replies: 23
- Views: 1081
Re: Single Bonds and Sigma Bonds
A single bond IS a sigma bond! For single through triple bonds they all have one sigma bond, and increase by one pi bond her extra bond starting with a single bond having 0 pi bonds, a double having 1 pi bond, ect.
- Sun Nov 29, 2020 4:34 pm
- Forum: Hybridization
- Topic: Sapling Week 7/8 HW #11
- Replies: 13
- Views: 550
Re: Sapling Week 7/8 HW #11
solving these problems is as simple as counting the amount of surrounding bonds/lone pairs and finding the nswer that has the amount of orbitals that match!
- Sun Nov 29, 2020 4:30 pm
- Forum: Hybridization
- Topic: Sapling #18
- Replies: 10
- Views: 412
Re: Sapling #18
There is a difference between how the hydrogens are placed on a 3D model depending on whether there are an even or odd number of carbons
- Sun Nov 29, 2020 4:19 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Sapling #17
- Replies: 10
- Views: 475
Re: Sapling #17
Because there are no negative charges or anything there are no resonance structures
- Sun Nov 29, 2020 3:11 pm
- Forum: Hybridization
- Topic: Sapling #11
- Replies: 19
- Views: 837
Re: Sapling #11
A tip my friend told me is to count up the number of lone pairs + the number of bonds, and then find the answer that counts up to that same number! For example sp3 would add up to 4 because there is a 1 in the s spot and a 3 in the p spot
- Sun Nov 15, 2020 11:59 pm
- Forum: Ionic & Covalent Bonds
- Topic: Sapling week 5 & 6 #16
- Replies: 7
- Views: 225
Re: Sapling week 5 & 6 #16
Why are O N and F atoms the only ones that bond with hyrdrogen for these types of problems ?
- Sun Nov 15, 2020 11:58 pm
- Forum: Formal Charge and Oxidation Numbers
- Topic: Sapling week 5 & 6 #5
- Replies: 20
- Views: 723
Re: Sapling week 5 & 6 #5
To find resonance you would take the number of valence electrons of the respective Element, and from that subtract the number of electrons/bonds around it. A single bond counts as one, and each electron counts as one
- Sun Nov 15, 2020 11:57 pm
- Forum: Formal Charge and Oxidation Numbers
- Topic: Sapling week 5 & 6 #5
- Replies: 20
- Views: 723
Re: Sapling week 5 & 6 #5
To find resonance you would take the number of valence electrons of the respective Element, and from that subtract the number of electrons/bonds around it. A single bond counts as one, and each electron counts as one
- Sun Nov 15, 2020 11:55 pm
- Forum: Ionic & Covalent Bonds
- Topic: Sapling week 5 & 6 #16
- Replies: 7
- Views: 225
Re: Sapling week 5 & 6 #16
The correct answer would be D because it is the only one that has has H connected to an O,N, and F molecule on each side.
- Sun Nov 08, 2020 11:42 pm
- Forum: Quantum Numbers and The H-Atom
- Topic: Are there subshells past f?
- Replies: 28
- Views: 1033
Re: Are there subshells past f?
I believe it goes up to f, but generally speaking we never really do work past d. It gets pretty confusing.
- Sun Nov 08, 2020 11:41 pm
- Forum: Lewis Structures
- Topic: Lewis acids and bases
- Replies: 10
- Views: 265
Re: Lewis acids and bases
You could use pKa, which is a numerical value representing the acidity of a molecule, or just look at the molecule itself to see if it would accept or give electrons.
- Sun Nov 08, 2020 11:38 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: What are orbitals?
- Replies: 10
- Views: 684
Re: What are orbitals?
To my knowledge, orbitals are more representations of where the electron can be found at any given time. For example, with an s orbital, there's a sphere of space where the electron can be found, whereas with the p orbital it's more of a peanut shape.
- Sun Nov 08, 2020 11:35 pm
- Forum: Bond Lengths & Energies
- Topic: Bond Lengths
- Replies: 10
- Views: 773
Re: Bond Lengths
Because the representation of double and single bonds is just that - A representation. In our experience thus far, most chemical representations on paper don't reveal the whole paper. For example, Lewis structures don't show resonance, the same way Newman structures don't show the valence electrons....
- Sun Nov 08, 2020 11:35 pm
- Forum: Bond Lengths & Energies
- Topic: Bond Lengths
- Replies: 10
- Views: 773
Re: Bond Lengths
Because the representation of double and single bonds is just that - A representation. In our experience thus far, most chemical representations on paper don't reveal the whole paper. For example, Lewis structures don't show resonance, the same way Newman structures don't show the valence electrons....
- Sun Nov 08, 2020 11:29 pm
- Forum: Trends in The Periodic Table
- Topic: memorizing trends
- Replies: 14
- Views: 275
Re: memorizing trends (Electron Affinity)
For electron affinity, it increases the more u head towards the top right of the periodic table, and the least electron affinitive element would be the bottom left element (Francium). hope this helps :)
- Sun Oct 18, 2020 4:36 pm
- Forum: Properties of Light
- Topic: Example during lecture 6
- Replies: 5
- Views: 257
Sapling Week 2 Question 9
What is the easiest way to calculate wavelength when an atom is transition between different energy levels (levels for n)?
- Sun Oct 18, 2020 4:28 pm
- Forum: Photoelectric Effect
- Topic: Sapling #4 Homework Part 2
- Replies: 9
- Views: 478
Sapling Week 2 Question 3
How do you determine wavelength, frequency, and energy from the amount of photons a wave of light produces?
- Sun Oct 18, 2020 2:12 pm
- Forum: Properties of Light
- Topic: Electric Waves and Magnetic Waves
- Replies: 2
- Views: 101
Electromagnetic Radiation
What are the different level of light radiations compared to eachother? For example gamma compared to ultraviolet, ect.
- Sun Oct 18, 2020 2:01 pm
- Forum: Properties of Electrons
- Topic: Electron Wave-Particle Duality
- Replies: 10
- Views: 311
Electromagnetic Waves
Hey guys, I just wanted to know what the difference between amplitude, wavelength, and frequencies are in wavelength illustrations. Also how do you determine Energy?
- Sun Oct 11, 2020 7:22 pm
- Forum: Empirical & Molecular Formulas
- Topic: Sapling Wk 1 Question 10
- Replies: 4
- Views: 235
Re: Sapling Wk 1 Question 10
What do the 1-bromopropane and the magnesium represent in the equation as pictured in the problem? Because as far as I've solved it I did not reference those elements
- Sun Oct 11, 2020 7:15 pm
- Forum: Molarity, Solutions, Dilutions
- Topic: Sapling HW Number 7
- Replies: 12
- Views: 450
Re: Sapling HW Number 7
Number 7 is quite simple, the only components are CaCl2 and water, it gives the total mass of the compound and the percent of that amount is CaCl2. Just Minus the percent of cacl2 from 100 to get the percent of water, then take the respective percent of what element you want from the total weight of...
- Sun Oct 11, 2020 7:10 pm
- Forum: Molarity, Solutions, Dilutions
- Topic: Sapling HW #6
- Replies: 8
- Views: 364
Re: Sapling HW #6
When I did this problem I made a lot of mistakes, such as mistaking the correct decimal points, but just double check that all ur calculations are right and youll be fine. Get the molar mass, and then anonther mistake I made was put v=m/n instead of v=n/m so watch out for stupid miscalculations.
- Sun Oct 11, 2020 6:45 pm
- Forum: Significant Figures
- Topic: Sapling #4
- Replies: 10
- Views: 569
Sapling #4
I am somewhat confused about the number 20.00, because the decimal is preceded by a 0, so would the sig fig rule that includes the 2 0s after the decimal point still count?
- Sun Oct 11, 2020 6:29 pm
- Forum: SI Units, Unit Conversions
- Topic: Avogadro's Constant
- Replies: 12
- Views: 654
Re: Avogadro's Constant
Avagadro's number represents 6.023 x 10^23, and is often used to calculate the number of particles in an element. It can be used to convert moles to number of things (particles, atoms, ect.) Other than that my knowledge of avagadro's number and its application in conversions is a little rusty hahaha.