Search found 41 matches

by Mayaal_Khan_4H
Fri Dec 07, 2018 5:50 pm
Forum: Administrative Questions and Class Announcements
Topic: test questions
Replies: 1
Views: 293

Re: test questions

8 questions with multiple parts each.
by Mayaal_Khan_4H
Mon Dec 03, 2018 2:07 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Ligand names
Replies: 7
Views: 819

Re: Ligand names

I found a quizlet for the ligand names from Chemistry Community 2016. The link is below:

https://quizlet.com/IsayanNatalie/folde ... y-14a/sets
by Mayaal_Khan_4H
Mon Dec 03, 2018 12:38 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: cis and trans
Replies: 1
Views: 259

Re: cis and trans

Drawing the lewis structure and then writing the name of the ligand will help you to distinguish whether it is a cis or trans molecule.
by Mayaal_Khan_4H
Mon Dec 03, 2018 12:34 pm
Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
Topic: Calculating pH
Replies: 3
Views: 377

Re: Calculating pH

pH can also be calculated by this formula: pH = -log[H+]
by Mayaal_Khan_4H
Tue Nov 27, 2018 1:46 pm
Forum: Dipole Moments
Topic: Hydrogen Bonding Strength
Replies: 2
Views: 361

Re: Hydrogen Bonding Strength

Hydrogen bonding is a strong intermolecular forces because it occurs between the hydrogen atom of one molecule and another atom of another molecule that has a high electronegativity value.
by Mayaal_Khan_4H
Tue Nov 27, 2018 1:41 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: Size and Strength of Attractive forces
Replies: 2
Views: 359

Re: Size and Strength of Attractive forces

As you increase the molar mass of a molecule, you are increasing the number of electrons in that molecule which then increases the molecule's attraction to other molecules, thus resulting in stronger London Dispersion Forces.
by Mayaal_Khan_4H
Tue Nov 27, 2018 1:24 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: ligands and dentates
Replies: 3
Views: 422

Re: ligands and dentates

A ligand is an atom or molecule attached to a central atom, usually a metallic element, in a coordination or complex compound. Ligands must have one or more lone pairs, they bind at: 1 site---> donate 1e- pair ---> Monodentate 2 sites--->donate 2e- pair ---> Bidentate 3 sites--->donate 3e- pair ----...
by Mayaal_Khan_4H
Tue Nov 27, 2018 1:16 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: T shaped
Replies: 6
Views: 580

Re: T shaped

AX3E2 means that the central atom is bonded to 3 atoms and has 2 lone pairs, since there are 2 lone pairs instead of 1, the bond angles change and therefore the shape changes from trigonal planar to T-shape
by Mayaal_Khan_4H
Mon Nov 19, 2018 9:00 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Determining bond type
Replies: 4
Views: 365

Re: Determining bond type

Single Bond = 1 sigma bond
Double Bond = 1 sigma bond + 1 pi bond
Triple Bond = 1 sigma bond + 2 pi bonds
by Mayaal_Khan_4H
Mon Nov 19, 2018 4:08 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Double bonds
Replies: 8
Views: 850

Re: Double bonds

Double bonds are seen as single bonds when you use the VESPR model, double bonds do not affect the VESPR model.
by Mayaal_Khan_4H
Tue Nov 13, 2018 12:42 pm
Forum: Student Social/Study Group
Topic: Homework 6
Replies: 5
Views: 641

Re: Homework 6

Daisy Valdez 4G wrote:What problems are we answering for homework for week 7?


For Week 7, we are answering problems from Outline 4 (Chapter 4 for 6th Edition).

https://lavelle.chem.ucla.edu/wp-conten ... ucture.pdf
by Mayaal_Khan_4H
Tue Nov 13, 2018 12:22 pm
Forum: Administrative Questions and Class Announcements
Topic: 14B Co-Requisites
Replies: 4
Views: 805

Re: 14B Co-Requisites

I don't think "my ucla" will let you enroll in Chem14B if you have not fulfilled the requirements. For Chem14B, you need to have taken Math 3B/31B or LS30B before or you could also take Math 3B/31B or LS 30B with Chem14B at the same time. Unfortunately, because you have not started the mat...
by Mayaal_Khan_4H
Tue Nov 13, 2018 12:18 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Polar vs. NonPolar
Replies: 5
Views: 606

Re: Polar vs. NonPolar

Polarity depends on the electronegativity difference between two elements, if you go across the periodic table, the electronegativity increases and if you go towards the left of the periodic table, the electronegativity decreases, for example, the electronegativity difference of Cl2 would be 0 since...
by Mayaal_Khan_4H
Tue Nov 06, 2018 3:08 pm
Forum: Ionic & Covalent Bonds
Topic: O vs N [ENDORSED]
Replies: 4
Views: 513

Re: O vs N [ENDORSED]

Ionization energy increases across a table because the valence shell of the elements as you go towards the right is nearly filled whereas as, as you go towards the left, the electrons have a low ionization energy from their willingness to lose electrons and become cations which is why Oxygen has a l...
by Mayaal_Khan_4H
Tue Nov 06, 2018 2:56 pm
Forum: Electronegativity
Topic: Electron affinity
Replies: 5
Views: 590

Re: Electron affinity

Like electronegativity, electron affinity increases across a period and up a group because the electrons added to energy levels become closer to the nucleus, thus a stronger attraction between the nucleus and its electrons.
by Mayaal_Khan_4H
Tue Nov 06, 2018 2:52 pm
Forum: Empirical & Molecular Formulas
Topic: Assumption of 100g
Replies: 2
Views: 1502

Re: Assumption of 100g

Sometimes the percentages don't add up to a 100 so you have to multiply the mass of each element by the molar mass so that the mass of all elects equal 1 to 100.
by Mayaal_Khan_4H
Tue Nov 06, 2018 2:50 pm
Forum: Formal Charge and Oxidation Numbers
Topic: Formal Charge of Oxygen
Replies: 6
Views: 1640

Re: Formal Charge of Oxygen

The formal charge depends on the arrangement of electrons around the element. Maybe Oxygen was arranged in a way in which there were more lone pairs than shared pairs which caused it to have a negative formal charge.
by Mayaal_Khan_4H
Tue Oct 30, 2018 4:18 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: 1E.13
Replies: 3
Views: 470

Re: 1E.13

Start removing electrons from the s-orbital because the d-orbital is best stable when it is half or full-filled.
by Mayaal_Khan_4H
Tue Oct 30, 2018 4:17 pm
Forum: Lewis Structures
Topic: Dots in Lewis Stucture
Replies: 14
Views: 1242

Re: Dots in Lewis Stucture

The order doesn't matter but first put one electron on each side and then start adding more when you have filled all sides with 1 electron.
by Mayaal_Khan_4H
Tue Oct 30, 2018 12:08 pm
Forum: Ionic & Covalent Bonds
Topic: HW 3.87 6TH EDITION
Replies: 1
Views: 272

Re: HW 3.87 6TH EDITION

CF4 because it has the shortest bond since short bonds=strong bonds
by Mayaal_Khan_4H
Mon Oct 22, 2018 12:36 pm
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: Shielding [ENDORSED]
Replies: 15
Views: 2153

Re: Shielding [ENDORSED]

Hello everyone, I'm struggling a bit with this concept. In the hw, it told us to find the ground state of elements (ex: Bi which has 83 electrons) and then the answer was [Xe]4f^(14)5d^(10)6s^(2)6p^(3). When it comes to elements with a high number of electrons is there another way to go about this ...
by Mayaal_Khan_4H
Mon Oct 22, 2018 12:31 pm
Forum: Administrative Questions and Class Announcements
Topic: Chem Community Due Date
Replies: 6
Views: 650

Re: Chem Community Due Date

Due date is midnight of Sunday.
by Mayaal_Khan_4H
Mon Oct 22, 2018 12:29 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Electron Configuration
Replies: 5
Views: 474

Re: Electron Configuration

Starting with the Nobel gas should be fine.
by Mayaal_Khan_4H
Mon Oct 22, 2018 12:18 pm
Forum: Administrative Questions and Class Announcements
Topic: Test Average
Replies: 4
Views: 434

Re: Test Average

michellebui_3L wrote:Where can you check the test average?


I think you will have to ask your TA what the test average is.
by Mayaal_Khan_4H
Fri Oct 19, 2018 7:38 pm
Forum: Quantum Numbers and The H-Atom
Topic: 4th Quantum number m subscript s [ENDORSED]
Replies: 1
Views: 285

Re: 4th Quantum number m subscript s [ENDORSED]

m subscript s is the electron spin quantum number, the electron can spin in two directions, +1/2 (spin up) or -1/2 (spin down).
by Mayaal_Khan_4H
Fri Oct 19, 2018 1:55 pm
Forum: Properties of Light
Topic: Test 2 [ENDORSED]
Replies: 15
Views: 1267

Re: Test 2 [ENDORSED]

Brandon Mo 1J wrote:On the class website, it says, "Test 2 covers all quantum material up to and including quantum numbers."

Does this mean that there will not be anything about orbitals or anything in chapter 2 (6th edition)?



I think quantum numbers are in chapter 2.
by Mayaal_Khan_4H
Wed Oct 17, 2018 2:02 pm
Forum: Properties of Light
Topic: Test 2 [ENDORSED]
Replies: 15
Views: 1267

Re: Test 2 [ENDORSED]

I think all of "Outline 2: The Quantum World" will be tested.
by Mayaal_Khan_4H
Wed Oct 17, 2018 1:57 pm
Forum: Student Social/Study Group
Topic: Test Grades
Replies: 4
Views: 567

Re: Test Grades

I think the test will be passed back to you during the discussion after the week you took the test.
by Mayaal_Khan_4H
Wed Oct 17, 2018 12:45 pm
Forum: Student Social/Study Group
Topic: Past Final Exams
Replies: 6
Views: 781

Re: Past Final Exams

Can anyone email to me as well? mayaal.khan@yahoo.com
by Mayaal_Khan_4H
Wed Oct 17, 2018 12:24 pm
Forum: Properties of Light
Topic: Mnemonic for em spectrum
Replies: 2
Views: 234

Re: Mnemonic for em spectrum

Thank you so much for posting this!!
by Mayaal_Khan_4H
Wed Oct 17, 2018 12:19 pm
Forum: Administrative Questions and Class Announcements
Topic: Required knowledge for test/midterm [ENDORSED]
Replies: 17
Views: 1441

Re: Grade [ENDORSED]

hey, so if I didn't do too well on the first test and I mean not well at all, will getting good scores on the next tests improve my grade? The tests don't weigh as much as the midterm and final do, if you do well on the midterms and final, and one of the three tests, then you are fine. The followin...
by Mayaal_Khan_4H
Mon Oct 15, 2018 2:58 pm
Forum: Properties of Light
Topic: List Of Equations
Replies: 2
Views: 133

Re: List Of Equations

Speed of light, c=λv, c=3.00*10^8 Momentum, p=mv Energy, E=pv Wavelength, lambda λ Planck's Constant, h=6.626 x 10^-34 joule*seconds Bohr Frequency Condition, ΔE=hv E(photon)=threshold energy-Ek En=-hR/n^2 Rydberg constant: R=3.29*10^15Hz Difference in energy levels, ΔE=E(final)-E(initial) De Brogli...
by Mayaal_Khan_4H
Mon Oct 15, 2018 2:18 pm
Forum: Student Social/Study Group
Topic: 6th Edition Answers
Replies: 2
Views: 1235

Re: 6th Edition Answers

You can also check out the solutions manual from Powell library for an hour.
by Mayaal_Khan_4H
Mon Oct 15, 2018 2:17 pm
Forum: Properties of Electrons
Topic: Constructive vs Destructive
Replies: 3
Views: 272

Re: Constructive vs Destructive

Constructive: Two waves combine to form a larger wave that has an amplitude which is larger than the amplitudes of the initial waves.
Destructive: Two waves combine but cancel out to form a smaller wave that has an amplitude which is smaller than the amplitudes of the initial waves.
by Mayaal_Khan_4H
Tue Oct 09, 2018 3:35 pm
Forum: Balancing Chemical Reactions
Topic: Element Names & Symbols
Replies: 2
Views: 410

Re: Element Names & Symbols

My TA said that a periodic table will be given to you on the day of the test and Mr. Lavelle said that you don't need to memorize any polyatomic ions.
by Mayaal_Khan_4H
Tue Oct 09, 2018 3:32 pm
Forum: SI Units, Unit Conversions
Topic: How does grading for discussion posts work?
Replies: 80
Views: 8781

Re: How does grading for discussion posts work?

I think that "in order for you to receive the 3 points for the discussion, you need to either post a question, answer a question or put a comment relevant to the question on a post, 3 times a week." that's what one of the TA's told me. Are the posts due by the time we have our discussion ...
by Mayaal_Khan_4H
Tue Oct 09, 2018 3:29 pm
Forum: Empirical & Molecular Formulas
Topic: when to multiply empirical formula [ENDORSED]
Replies: 9
Views: 4562

Re: when to multiply empirical formula [ENDORSED]

You need to multiple the answer by the smallest possible number which would turn the answer to a whole number. For example, if your answer is 1.33, you will have to multiply it by 3 to get 4.
by Mayaal_Khan_4H
Fri Oct 05, 2018 9:07 pm
Forum: Limiting Reactant Calculations
Topic: H11
Replies: 1
Views: 181

Re: H11

Balance the first equation: 3 Fe2O3 + CO --------> 2 Fe3O4 + CO2 Balance the second equation: Fe3O4 + 4CO -------> 3 Fe + 4 CO2 We don't bring the moles of Fe3O4 and CO2 in the second equation because they are reactants not products in the second equation and the second question is now a completely ...
by Mayaal_Khan_4H
Fri Oct 05, 2018 8:56 pm
Forum: SI Units, Unit Conversions
Topic: How does grading for discussion posts work?
Replies: 80
Views: 8781

Re: How does grading for discussion posts work?

I think that "in order for you to receive the 3 points for the discussion, you need to either post a question, answer a question or put a comment relevant to the question on a post, 3 times a week." that's what one of the TA's told me.
by Mayaal_Khan_4H
Fri Oct 05, 2018 8:51 pm
Forum: Properties of Light
Topic: Review of high.school quantum clarification
Replies: 1
Views: 108

Re: Review of high.school quantum clarification

The higher the atomic number of an atom is, the higher you go up the energy levels. Energy levels are counted as whole numbers starting from 1. The atom, Carbon, contains 6 electrons which can be fitted in 2 energy levels. But, the atom, Aluminum, contains 13 electrons which can be fitted in to 3 en...
by Mayaal_Khan_4H
Fri Oct 05, 2018 8:39 pm
Forum: Balancing Chemical Reactions
Topic: Balancing reactions tips
Replies: 29
Views: 2152

Re: Balancing reactions tips

I would suggest writing the numbers down under the reaction sign and solving them right there. I will provide you with an example: So, balance H2 + O2 ------> H2O by writing down the numbers of moles each reactant and product has. Having the moles written down 2 =H= 2 2 =O= 1 makes it easy for you t...

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