Search found 61 matches

by 805373590
Thu Jan 23, 2020 2:55 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: pKa to Kb
Replies: 12
Views: 38

Re: pKa to Kb

You can go from pka to ka by taking 10 to the power of negative pka and when you found ka you can easily divide 10 to the power of negative 14 by ka to get kb
by 805373590
Thu Jan 23, 2020 2:52 pm
Forum: Ideal Gases
Topic: Kc vs Kp
Replies: 26
Views: 64

Re: Kc vs Kp

You can use kp when the reactants and products are gases and the partial pressures of the gases are given rather than their concentrations
by 805373590
Thu Jan 23, 2020 2:51 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: ice table
Replies: 13
Views: 37

Re: ice table

No
Since solids and liquids are not written in the k expression we don't need to include them in the ice tables
by 805373590
Thu Jan 23, 2020 2:50 pm
Forum: Student Social/Study Group
Topic: midterm/final
Replies: 9
Views: 34

Re: midterm/final

The tests are more like the homework problem whereas the midterm and final have more conceptual questions
by 805373590
Thu Jan 23, 2020 2:49 pm
Forum: Ideal Gases
Topic: test 1
Replies: 9
Views: 32

Re: test 1

Test one only includes outlines 1 and 2 which include the chemical equilibrium and the acid and base information from this quarter
by 805373590
Fri Jan 17, 2020 5:02 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Quadratic
Replies: 10
Views: 32

Re: Quadratic

You will test out the two answers and the answer that is less than the initial answer will be the correct one
by 805373590
Fri Jan 17, 2020 5:00 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: ICE
Replies: 5
Views: 41

Re: ICE

ICE tables are used when the problem is only providing the initial concentrations and we are trying to find the ph or ooh of weak acids or bases
by 805373590
Fri Jan 17, 2020 4:59 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Kc & Kp
Replies: 12
Views: 34

Re: Kc & Kp

We use kc when we are dealing with concentrations but we only use kp when we are dealing with partial pressures of gases.
by 805373590
Fri Jan 17, 2020 4:58 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Tips for Test
Replies: 16
Views: 53

Re: Tips for Test

I think the best tip would be to do as many of the homework problems as possible to better understand the material and test yourself on all the material covered in lectures
by 805373590
Fri Jan 17, 2020 4:57 pm
Forum: General Science Questions
Topic: Test 1 [ENDORSED]
Replies: 13
Views: 86

Re: Test 1 [ENDORSED]

Test one starts this week in discussion sections starting on Tuesday. The test will cover the first two outlines on dr Lavelle's chem 14b website.
by 805373590
Fri Jan 10, 2020 1:27 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Units for K
Replies: 10
Views: 44

Re: Units for K

Since k is a ratio constant the units of the products and reactants concentration cancel out making k a unitless constant.
by 805373590
Fri Jan 10, 2020 1:26 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Change in k
Replies: 11
Views: 40

Change in k

How is it that a change in concentration does not change the value of k?
by 805373590
Fri Jan 10, 2020 1:24 pm
Forum: Ideal Gases
Topic: pressure [ENDORSED]
Replies: 13
Views: 192

Re: pressure [ENDORSED]

Yes, this is easily proven using the ideal gas law pv=nRT
by 805373590
Fri Jan 10, 2020 1:22 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Value of K
Replies: 4
Views: 25

Re: Value of K

Since K is a ratio the threshold would depend on the molar ratio of the products and reactants given in the reaction.
by 805373590
Fri Jan 10, 2020 1:20 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: Calculating eq with percentages of reaction
Replies: 3
Views: 9

Re: Calculating eq with percentages of reaction

When given percentages you can easily find the moles of the products and reactants. From there you can calculate the molarity and concentration and plug it into the Kc formula to calculate the equilibrium constant of the reaction.
by 805373590
Sun Dec 01, 2019 2:40 pm
Forum: Naming
Topic: Final Exam?
Replies: 20
Views: 128

Re: Final Exam?

it is a cumulative final from all of the 6 outlines: Outline 1: Review of Chemical & Physical Principles Outline 2: The Quantum World Outline 3: Chemical Bonds Outline 4: Molecular Shape and Structure Outline 5: Coordination Compounds and Their Biological Importance Outline 6: Acid and Base Stru...
by 805373590
Sun Dec 01, 2019 2:39 pm
Forum: Lewis Acids & Bases
Topic: Define Acid and Base
Replies: 7
Views: 46

Re: Define Acid and Base

I attached a helpful summary of the definitions
by 805373590
Sun Dec 01, 2019 2:36 pm
Forum: Naming
Topic: Names of ligands
Replies: 4
Views: 31

Re: Names of ligands

https://lavelle.chem.ucla.edu/wp-conten ... pounds.pdf
Dr. Lavelle sent this link and it is very helpful.
by 805373590
Sun Dec 01, 2019 2:34 pm
Forum: Bronsted Acids & Bases
Topic: Distinguishing between Strong and Weak Acids/Bases
Replies: 7
Views: 33

Re: Distinguishing between Strong and Weak Acids/Bases

I think we only need to memorize the strong acids and bases outlined in the table from the fundamentals section J.
by 805373590
Sun Dec 01, 2019 2:30 pm
Forum: Properties & Structures of Inorganic & Organic Acids
Topic: question 6.A
Replies: 1
Views: 31

question 6.A

can someone please explain how to do part b and c of this homework problem? 6A.9 Which of the following can be classified as reactions between Brønsted acids and bases? For those that can be so classified, identify the acid and the base. (Hint: It might help to write the net ionic equations.) (b) NH...
by 805373590
Sun Nov 24, 2019 12:22 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Identifying Polydentate Ligands
Replies: 5
Views: 25

Re: Identifying Polydentate Ligands

A polydentate ligand has prefixes that indicate the number of donor atoms and more than 2 lewis base sites, such as lone pair donating sites used to bond to a central atom or ion.
by 805373590
Sun Nov 24, 2019 12:18 pm
Forum: Naming
Topic: Naming Rules
Replies: 2
Views: 30

Re: Naming Rules

https://lavelle.chem.ucla.edu/wp-conten ... pounds.pdf
Professor Lavelle emailed this list.
by 805373590
Sun Nov 24, 2019 12:07 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Bond Angle of bent
Replies: 17
Views: 84

Re: Bond Angle of bent

look at it as a trigonal planar shape with a lone pair instead of an atom, therefore, making a bond of less than 120 degrees.
by 805373590
Sun Nov 24, 2019 12:04 pm
Forum: General Science Questions
Topic: Sig Figs
Replies: 7
Views: 78

Re: Sig Figs

you can lose 1-2 points for the wrong number of sig figs.
by 805373590
Sun Nov 24, 2019 12:01 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Bent vs linear
Replies: 56
Views: 290

Re: Bent vs linear

the bent shape has 1-2 lone pairs whereas linear has 0 0r 3 in the case of I3.
by 805373590
Sat Nov 16, 2019 2:33 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Determining if a molecule is polar or non polar
Replies: 9
Views: 51

Re: Determining if a molecule is polar or non polar

when determining the polarity we only need to take into account the electronegativity trends in the periodic table, therefore, don't need to memorize exact values.
by 805373590
Sat Nov 16, 2019 2:29 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
Replies: 5
Views: 28

Re: Hydrogen Bonding

Hydrogen bonding is a special type of dipole-dipole in which one of the atoms is hydrogen, is covalently bonded to an electronegative atom, such as oxygen, chlorine, or fluorine.
by 805373590
Sat Nov 16, 2019 2:25 pm
Forum: Administrative Questions and Class Announcements
Topic: Class Grading
Replies: 3
Views: 40

Re: Class Grading

according to the syllabus "Each test and exam has a total score but is not assigned a grade. Only at the end of the class when the class average score (out of 500 points) is known are final grades assigned. This class does not use a curve".
by 805373590
Sat Nov 16, 2019 2:21 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: VSPER Formula
Replies: 2
Views: 24

Re: VSPER Formula

I think he will most likely give us a compound and ask us to identify its shape.
by 805373590
Thu Nov 07, 2019 10:48 am
Forum: Formal Charge and Oxidation Numbers
Topic: Do higher electronegativity atoms tend to draw more electrons to them?
Replies: 6
Views: 25

Re: Do higher electronegativity atoms tend to draw more electrons to them?

Yes because electronegativity describes the tendency of an atom to attract a pair of electrons making it more negative.
by 805373590
Thu Nov 07, 2019 10:45 am
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: Bohr Frequency
Replies: 6
Views: 46

Re: Bohr Frequency

When energy is absorbed the delta E is positive therefore goes from lower n to higher n.
by 805373590
Thu Nov 07, 2019 10:38 am
Forum: Electronegativity
Topic: Trend of Electronegativity
Replies: 22
Views: 102

Re: Trend of Electronegativity

The trend for electronegativity is the same for the trend in atomic spectra and ionization energy with some exceptions. It increases from right to left and decreases from up to down a group.
by 805373590
Thu Nov 07, 2019 10:36 am
Forum: Photoelectric Effect
Topic: Intensity in Photoelectric Effect
Replies: 6
Views: 73

Re: Intensity in Photoelectric Effect

Electrons will only be emitted if the energy of a photon reaches a certain threshold of energy. Therefore increasing the intensity will have no impact on the energy of the phon and rather the increase in frequency will increase the energy of photon therefore ejecting more electrons. This proves the ...
by 805373590
Thu Nov 07, 2019 10:30 am
Forum: Electronegativity
Topic: Karen's worksheet #12
Replies: 3
Views: 58

Re: Karen's worksheet #12

C O is more polar because of the greater difference in electronegativity
by 805373590
Thu Nov 07, 2019 10:23 am
Forum: Bond Lengths & Energies
Topic: Test 2 Topics
Replies: 40
Views: 364

Re: Test 2 Topics

Test 2 will cover what we went over in class in outline 2 but was excluded from the midterm + what we learn after the midterm up to the test
by 805373590
Sun Nov 03, 2019 5:03 pm
Forum: Coordinate Covalent Bonds
Topic: coordinate covalent bond
Replies: 2
Views: 23

Re: coordinate covalent bond

covalent bond: both atoms are involved in the formation of bond. coordination bond: only one atom is involved.
by 805373590
Sun Nov 03, 2019 5:01 pm
Forum: Bond Lengths & Energies
Topic: Midterm Question
Replies: 5
Views: 59

Re: Midterm Question

the midterm is to topic 2d and according to the outline we have to be able to "List the factors affecting the covalent bond length and explain the effect of each".
by 805373590
Sun Nov 03, 2019 4:57 pm
Forum: Administrative Questions and Class Announcements
Topic: Homework Due this week
Replies: 2
Views: 28

Re: Homework Due this week

I think as long as the practice problems relate to what is being taught in lectures then it'll be sufficient for the homework.
by 805373590
Sun Nov 03, 2019 4:55 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: paul and hundd rules
Replies: 4
Views: 34

Re: paul and hundd rules

yes we need to know them because one of the questions on the dino nuggets midterm review sheet asked which rules were not being followed and you had to know the rules in order to answer the questions.
by 805373590
Sun Nov 03, 2019 4:48 pm
Forum: Administrative Questions and Class Announcements
Topic: TOPICS for Midterm help
Replies: 2
Views: 28

Re: TOPICS for Midterm help

the midterm will cover outline 1 (fundamentals, covered in test 1) and 2(the quantum world) completely and outline 3 (chemical bonds) up to topic 2d.
by 805373590
Sat Oct 26, 2019 1:05 pm
Forum: Trends in The Periodic Table
Topic: Ionization energy
Replies: 12
Views: 91

Ionization energy

Can someone please explain how ionization energy measured
by 805373590
Sat Oct 26, 2019 1:02 pm
Forum: Hybridization
Topic: Electrons
Replies: 13
Views: 365

Re: Electrons

electron is promoted when it absorbs a photon to jump from a low energy level orbital to a higher energy level orbital
by 805373590
Sat Oct 26, 2019 12:57 pm
Forum: Formal Charge and Oxidation Numbers
Topic: FC in lecture
Replies: 4
Views: 48

Re: FC in lecture

Delocalization increases stability by resonance because it increases the bonding between atoms and spreads energy over a larger area.
by 805373590
Sat Oct 26, 2019 12:53 pm
Forum: Ionic & Covalent Bonds
Topic: Electronegativity
Replies: 4
Views: 38

Re: Electronegativity

Electronegativity: tendency of an atom to attract an electron
Ionization energy: required energy to remove an electron from an atom
by 805373590
Sat Oct 26, 2019 12:48 pm
Forum: Trends in The Periodic Table
Topic: ionic radius
Replies: 3
Views: 21

Re: ionic radius

The ionic radius is half the distance between atomic ions in a crystal lattice and follows trends in the periodic table.
by 805373590
Sun Oct 20, 2019 2:30 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Exceptions for Electron Configuration
Replies: 6
Views: 24

Re: Exceptions for Electron Configuration

exceptions for electron configurations:
Cu-(Ar)3d^10 4s^1.
Cr-[Ar] 3d5 4s1
by 805373590
Sun Oct 20, 2019 2:27 pm
Forum: DeBroglie Equation
Topic: Mass of electron and photon
Replies: 5
Views: 46

Re: Mass of electron and photon

memorization is not required and professor Lavelle will give us the required information on each test.
by 805373590
Sun Oct 20, 2019 2:24 pm
Forum: Administrative Questions and Class Announcements
Topic: Advice on Homework
Replies: 13
Views: 149

Re: Advice on Homework

I think even though we are only obliged to do 5 questions it would be better in the long run if we looked at at least half of the fundamental questions professor outline on the class website.
by 805373590
Sun Oct 20, 2019 2:22 pm
Forum: Heisenberg Indeterminacy (Uncertainty) Equation
Topic: Advice
Replies: 6
Views: 61

Re: Advice

I found the pre/post assessment questions to be very helpful also professor Lavelle outlined the important questions in the textbook that correspond to the topics he discussed in class.
by 805373590
Sun Oct 20, 2019 2:20 pm
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: how to prepare
Replies: 22
Views: 139

Re: how to prepare

I suggest finding a group of people you are comfortable with and make a study group. just remember everyone gets stressed but college is the time to conquer your fears.
by 805373590
Sun Oct 13, 2019 3:40 pm
Forum: Properties of Light
Topic: 1A.9
Replies: 5
Views: 34

Re: 1A.9

The energy of a photon is equal to Planck's constant multiplied by the frequency of light. E = hf
by 805373590
Sun Oct 13, 2019 3:32 pm
Forum: Properties of Light
Topic: 1A.5
Replies: 3
Views: 25

Re: 1A.5

Increasing to decreasing:
Yrays
Xrays
Ultraviolet rays
Visible light
Microwaves
by 805373590
Sun Oct 13, 2019 3:32 pm
Forum: Properties of Light
Topic: 1A.5
Replies: 3
Views: 25

Re: 1A.5

Increasing to decreasing:
Yrays
Xrays
Ultraviolet rays
Visible light
Microwaves
by 805373590
Sun Oct 13, 2019 3:20 pm
Forum: Properties of Light
Topic: Photon vs Wave Model
Replies: 5
Views: 30

Re: Photon vs Wave Model

The frequency (number of waves per second) of a photon determines its energy whereas the number of photons determines the intensity of light.
by 805373590
Fri Oct 11, 2019 5:48 pm
Forum: DeBroglie Equation
Topic: q 34
Replies: 1
Views: 26

q 34

how do we determine is our answer is reasonable in "If an electron (mass 9.11 x 10-31 kg) has an associated wavelength of 7.28 x 10-9 m, what is its speed? Is your answer reasonable, why?'
by 805373590
Fri Oct 11, 2019 5:46 pm
Forum: DeBroglie Equation
Topic: q 24
Replies: 2
Views: 24

q 24

can someone explain this question to me "When neutrons pass through a crystal is a diffraction pattern observed?
What does this experiment tell us about neutrons?"
by 805373590
Tue Oct 01, 2019 8:10 pm
Forum: Administrative Questions and Class Announcements
Topic: Test #1
Replies: 3
Views: 82

Re: Test #1

Hello does anyone know whether our first test is multiple choice or free response?
by 805373590
Tue Oct 01, 2019 7:56 pm
Forum: Accuracy, Precision, Mole, Other Definitions
Topic: Calculation of Mass of One Molecule
Replies: 3
Views: 49

Re: Calculation of Mass of One Molecule

The mass of one mole of water is equal to 2 times the molar mass of hydrogen (2x1.008 g) plus the molar mass of oxygen (16 g) which is equal to 18.016 g. 1 mole of water is equal to 6.022 x 10^23 molecules so to find the molar mass of one molecule of water all you need to do is divide 18.016 by (6.0...
by 805373590
Tue Oct 01, 2019 7:40 pm
Forum: Administrative Questions and Class Announcements
Topic: Advice from a Medical Student - Part II [ENDORSED]
Replies: 130
Views: 3391

Re: Advice from a Medical Student - Part II [ENDORSED]

As a confused incoming freshman hoping to pursue the pre health route, this is truly inspiring. Tahnk you for sharing.
by 805373590
Tue Oct 01, 2019 5:51 pm
Forum: Administrative Questions and Class Announcements
Topic: Test #1
Replies: 2
Views: 58

Re: Test #1

I think the test is only on Empirical and Molecular Formulas,Balancing Chemical Equations, Limiting Reactant Calculations, Molarity and Dilution of a Solution outlined in the fundamentals section of the textbook.

Go to advanced search