Search found 58 matches

by Simran Rai 4E
Sun Mar 17, 2019 9:16 am
Forum: Zero Order Reactions
Topic: Zero order reaction
Replies: 8
Views: 48

Re: Zero order reaction

It is zero order if its concentration has no effect on the rate.
by Simran Rai 4E
Sun Mar 17, 2019 9:13 am
Forum: General Rate Laws
Topic: Slow elementary step
Replies: 2
Views: 29

Re: Slow elementary step

The rate cannot be any faster than its slowest step, therefore, it determines the rate.
by Simran Rai 4E
Sun Mar 17, 2019 9:11 am
Forum: Arrhenius Equation, Activation Energies, Catalysts
Topic: Arrhenius eq
Replies: 3
Views: 44

Re: Arrhenius eq

In class, Dr. Lavelle had said to assume A=1 unless otherwise stated.
by Simran Rai 4E
Sun Mar 17, 2019 9:10 am
Forum: General Rate Laws
Topic: mmol units
Replies: 2
Views: 41

Re: mmol units

I think you'd only need to convert so you can have the same units across. One of the problems has mmol and mol so units for mmol were converted to mol. But the other problem had only mmol units, so no conversion was necessary. The units of the initial rate and initial concentrations should match up.
by Simran Rai 4E
Sat Mar 16, 2019 12:08 pm
Forum: Administrative Questions and Class Announcements
Topic: Test Location 14B W19
Replies: 3
Views: 68

Re: Test Location 14B W19

Here you go...
by Simran Rai 4E
Sat Mar 16, 2019 11:59 am
Forum: Administrative Questions and Class Announcements
Topic: LYNDON'S PORK RAMEN REVIEW
Replies: 37
Views: 2000

Re: LYNDON'S PORK RAMEN REVIEW

Thank You Lyndon!
by Simran Rai 4E
Fri Mar 15, 2019 8:33 pm
Forum: Student Social/Study Group
Topic: Studying for the Final
Replies: 25
Views: 378

Re: Studying for the Final

That along with the making sure to know everything mentioned in the outlines.
by Simran Rai 4E
Sat Mar 09, 2019 11:09 pm
Forum: Reaction Mechanisms, Reaction Profiles
Topic: Microscopic reversibility
Replies: 4
Views: 45

Re: Microscopic reversibility

Microscopic reversibility assumes that the reaction has the same pathway for forward and reverse directions.
by Simran Rai 4E
Sat Mar 09, 2019 10:21 pm
Forum: Second Order Reactions
Topic: Final
Replies: 30
Views: 343

Re: Final

As everyone said, it is cumulative, and the best preparation is to look at the outlines for each optic covered and make sure you understand all of the bullet points listed. Dr. Labels suggests practicing textbook homework problems is the best preparation.
by Simran Rai 4E
Sat Mar 09, 2019 10:16 pm
Forum: Second Order Reactions
Topic: rate constant k
Replies: 3
Views: 30

Re: rate constant k

You can think about it as a rate not proceeding negatively. It can be slow, or you can have a reverse rate, but a “negative” rate is not possible.
by Simran Rai 4E
Wed Feb 27, 2019 6:24 am
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Galvanic Cell Inert Component
Replies: 1
Views: 40

Re: Galvanic Cell Inert Component

An inert electrode is used when there is a gas/ion electrode reaction or when both oxidized and reduced species are in the same solution, meaning there's no conducting solid.
by Simran Rai 4E
Mon Feb 25, 2019 5:37 pm
Forum: General Science Questions
Topic: Test #2
Replies: 2
Views: 86

Re: Test #2

This is from the website :)
by Simran Rai 4E
Sun Feb 24, 2019 12:00 am
Forum: Student Social/Study Group
Topic: Post All Chemistry Jokes Here
Replies: 7337
Views: 825509

Re: Post All Chemistry Jokes Here

:o
by Simran Rai 4E
Sat Feb 23, 2019 11:51 pm
Forum: Calculating Work of Expansion
Topic: Equations for work
Replies: 7
Views: 87

Re: Equations for work

Adding to that, for the third equation, when pressure is changing, you'd use w=-nRT ln (p1/p2).
by Simran Rai 4E
Sat Feb 23, 2019 11:44 pm
Forum: Van't Hoff Equation
Topic: Galvanic/Voltaic Cell
Replies: 2
Views: 49

Re: Galvanic/Voltaic Cell

From what I've read, they're used interchangeably.
by Simran Rai 4E
Fri Feb 15, 2019 1:46 pm
Forum: Gibbs Free Energy Concepts and Calculations
Topic: Gibbs free energy
Replies: 5
Views: 68

Re: Gibbs free energy

If the value is negative, then it's spontaneous and favors product formation and if the value is positive, then it's non spontaneous and does not favor formation of products.
by Simran Rai 4E
Fri Feb 15, 2019 1:43 pm
Forum: Gibbs Free Energy Concepts and Calculations
Topic: work and Gibbs Free Energy
Replies: 2
Views: 52

Re: work and Gibbs Free Energy

If Gibbs free energy is negative, that means the process is spontaneous and releases energy. Free energy is described as the energy that is available to do work.
by Simran Rai 4E
Fri Feb 15, 2019 1:37 pm
Forum: Concepts & Calculations Using Second Law of Thermodynamics
Topic: Microstate
Replies: 7
Views: 112

Re: Microstate

When there are more microstates, there is increased entropy. This is because there is greater positional/residual vibration between molecules and that lends to greater disorder.
by Simran Rai 4E
Fri Feb 08, 2019 2:32 am
Forum: Administrative Questions and Class Announcements
Topic: Midterm Review Sessions
Replies: 1
Views: 103

Re: Midterm Review Sessions

The TA or LA will usually post a practice worksheet on here for us to do before the review session, so that way they can just go through the solutions and answer any questions. But sometimes no worksheets are given and it's more note dependent based on the review session you attend.
by Simran Rai 4E
Fri Feb 01, 2019 10:09 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: Different Kinds of Symptoms
Replies: 6
Views: 82

Re: Different Kinds of Symptoms

Insulation only helps identify isolated systems. If there is no insulation you'd still have to determine whether the system was open or closed.
by Simran Rai 4E
Fri Feb 01, 2019 10:01 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Enthalpies
Replies: 5
Views: 58

Re: Enthalpies

Yes, an increase of enthalpy means that the system was supplied with energy/heat. ^
by Simran Rai 4E
Fri Feb 01, 2019 9:58 pm
Forum: Phase Changes & Related Calculations
Topic: Chemical potential energy
Replies: 4
Views: 55

Re: Chemical potential energy

Yes, you should get the same answer if you do the long method. ^
by Simran Rai 4E
Sat Jan 26, 2019 11:54 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Enthalpy Units
Replies: 7
Views: 85

Re: Enthalpy Units

The standard enthalpy of formation is the enthalpy change when 1 mole of a substance is formed from its element(s). Note that all the substances should be in standard state.
by Simran Rai 4E
Wed Jan 23, 2019 11:30 am
Forum: Ideal Gases
Topic: atm vs. bar?
Replies: 23
Views: 346

Re: atm vs. bar?

Regarding pressure, they're both just units measurements. But if you wanted to figure out concentration you would need to use atm. For example, if you're given partial pressure but the units are in bar and you want to use PV=nRT to find concentration (with volume given), you'd need to convert to atm...
by Simran Rai 4E
Tue Jan 22, 2019 4:19 pm
Forum: Administrative Questions and Class Announcements
Topic: Homework for Week 3
Replies: 5
Views: 111

Re: Homework for Week 3

Screen Shot 2019-01-22 at 4.15.59 PM.png
This is what we got in the email
by Simran Rai 4E
Sun Jan 20, 2019 11:04 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: The Conjugate Seesaw
Replies: 13
Views: 149

Re: The Conjugate Seesaw

MadelineHlobik wrote:Does Kw=Ka*Kb and Kw=[H3O][OH]


Yes, so since Kw = 10^-14, [H30+] has to be 10^-7 and [OH-] has to be 10^-7 as well.
by Simran Rai 4E
Sun Jan 20, 2019 10:59 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Pressure Notation
Replies: 5
Views: 75

Re: Pressure Notation

Kp should not have any units because it is an activity. ^
by Simran Rai 4E
Sun Jan 20, 2019 10:56 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: Q VS. K
Replies: 13
Views: 142

Re: Q VS. K

K is basically the Q, but at equilibrium.
by Simran Rai 4E
Fri Jan 11, 2019 11:18 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Concentration of P using the Quadratic Formula
Replies: 3
Views: 44

Re: Concentration of P using the Quadratic Formula

Also keep in mind to discard the negative answer (of the two) you get because the concentration must always be a positive value.
by Simran Rai 4E
Fri Jan 11, 2019 11:12 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: Changing Pressure
Replies: 6
Views: 80

Re: Changing Pressure

Adding an inert gas wouldn't affect the equilibrium because the concentrations of the reactant and product would remain the same, meaning there would be no change in the equation.
by Simran Rai 4E
Fri Jan 11, 2019 11:07 pm
Forum: Ideal Gases
Topic: Notation [ENDORSED]
Replies: 5
Views: 83

Re: Notation [ENDORSED]

Yes, my TA usually uses parenthesis or nothing at all when doing a problem with partial pressure. With concentration, brackets are always used.
by Simran Rai 4E
Sun Dec 09, 2018 6:43 am
Forum: Biological Examples
Topic: Cisplatin
Replies: 7
Views: 125

Re: Cisplatin

904837647 wrote:Will cisplatin be apart of what we need to know on the final?


The syllabus says "Discuss well-known examples of coordination compounds used as chemotherapy drugs." so it would be a good idea to know it.
by Simran Rai 4E
Sun Dec 09, 2018 6:40 am
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Ligand order
Replies: 1
Views: 39

Re: Ligand order

They are namedin alphabetical order (ignoring Greek prefixes). Ex: for pentaammine, you would look at the A in ammine rather than the P in penta.
by Simran Rai 4E
Sun Dec 09, 2018 6:31 am
Forum: Polarisability of Anions, The Polarizing Power of Cations
Topic: Polarizability vs. Polarizing Power
Replies: 2
Views: 98

Re: Polarizability vs. Polarizing Power

Polarizability is how easy it is to pull the electron cloud of a molecule, whereas polarizing power is how good an atom is at pulling on bonding electrons. They are inversely related.
by Simran Rai 4E
Sun Dec 09, 2018 6:24 am
Forum: Polarisability of Anions, The Polarizing Power of Cations
Topic: polarizability
Replies: 1
Views: 53

Re: polarizability

That's correct.
by Simran Rai 4E
Sun Dec 09, 2018 6:22 am
Forum: Polarisability of Anions, The Polarizing Power of Cations
Topic: polarizing power
Replies: 3
Views: 131

Re: polarizing power

Polarizability is how easy it is to pull the electron cloud of a molecule, whereas polarizing power is how good an atom is at pulling on bonding electrons. They are inversely related.
by Simran Rai 4E
Sun Dec 09, 2018 6:19 am
Forum: Determining Molecular Shape (VSEPR)
Topic: Polarity
Replies: 2
Views: 73

Re: Polarity

No, if there's multiple lone pairs, their magnitude/direction can cancel out leaving you with a non polar molecule.
by Simran Rai 4E
Sun Dec 09, 2018 6:17 am
Forum: Naming
Topic: ethylenediamine
Replies: 1
Views: 46

Re: ethylenediamine

That's right, because it already has "di" in its name.
by Simran Rai 4E
Sat Dec 08, 2018 4:12 pm
Forum: Administrative Questions and Class Announcements
Topic: FINAL PRACTICE - Lyndon's Churro Review Session [ENDORSED]
Replies: 118
Views: 4699

Re: FINAL PRACTICE - Lyndon's Churro Review Session [ENDORSED]

These practice problems and review sessions are so helpful. Thank you Lyndon!
by Simran Rai 4E
Sat Dec 08, 2018 4:10 pm
Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
Topic: Calculating pH and the pOH
Replies: 2
Views: 40

Re: Calculating pH and the pOH

You would first find the pH by calculating pH=-log[H3O+] and then subtract your answer from 14 to get the POH.
by Simran Rai 4E
Sat Dec 08, 2018 4:07 pm
Forum: Naming
Topic: adding "ion" at the end of a name
Replies: 4
Views: 57

Re: adding "ion" at the end of a name

Lyndon had mentioned in his review session that it's good practice to do so, just to be safe. However I don't think you'd be docked points if you didn't add it.
by Simran Rai 4E
Sat Dec 08, 2018 4:05 pm
Forum: General Science Questions
Topic: FINAL
Replies: 3
Views: 130

Re: FINAL

Dr. Lavelle had sent out this link in an email explaining that this is a topic we'll cover in 14B.

viewtopic.php?f=60&t=38752
by Simran Rai 4E
Sat Dec 08, 2018 4:02 pm
Forum: Student Social/Study Group
Topic: Structure of the final
Replies: 4
Views: 136

Re: Structure of the final

Lavelle had said in class that it would be similar to the structure of the midterm, so I'm guessing about 8 questions with multiple parts to them and maybe a couple multiple choice questions.
by Simran Rai 4E
Tue Nov 27, 2018 10:05 am
Forum: Hybridization
Topic: Number
Replies: 2
Views: 55

Re: Number

Hybridization is based on regions of electron density. Therefore lone pairs would be included.
by Simran Rai 4E
Sun Nov 25, 2018 11:56 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Sigma and Pi Bonds
Replies: 3
Views: 55

Re: Sigma and Pi Bonds

Sigma bonds allow for free rotation of atoms. With pi bonds the whole molecule has to rotate, and single atoms cannot rotate freely.
by Simran Rai 4E
Sun Nov 25, 2018 11:49 pm
Forum: Electronegativity
Topic: Electronegativity Values
Replies: 4
Views: 134

Re: Electronegativity Values

The electronegativity values will be given to us in a problem. Otherwise, just follow the electronegativity trend for the periodic table to gauge if the values are lesser or greater than a value given.
by Simran Rai 4E
Sun Nov 25, 2018 11:45 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: VSEPR
Replies: 9
Views: 72

Re: VSEPR

The stronger the bond, the greater the repulsion strength. For example, a triple bond has greater repulsion strength than a double than a single bond.
by Simran Rai 4E
Sun Nov 18, 2018 11:23 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Dipole moments
Replies: 8
Views: 96

Re: Dipole moments

It's also helpful to consider dipole moments similar to vectors. We would take into account magnitude and direction when cancelling out/ adding up vectors, and the same idea applies to dipole moments.
by Simran Rai 4E
Sun Nov 18, 2018 11:17 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: lone pair influence on shape
Replies: 12
Views: 148

Re: lone pair influence on shape

Can someone explain the difference between bent and linear? A linear shape is when the bond angles are 180 degrees exactly. This could even take place in the presence of 2 or more lone pairs depending on the amount of regions of electron density. A bent shape, however occurs when the linear shape i...
by Simran Rai 4E
Sun Nov 18, 2018 11:06 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: lone pair influence on shape
Replies: 12
Views: 148

Re: lone pair influence on shape

Also in discussion, my TA had said that paired electrons are more repulsed by lone pairs of electrons than they are by other bonded pairs of electrons. Which can also explain why they'd more readily move closer to another bonded pair in the presence of lone electrons.
by Simran Rai 4E
Sun Nov 18, 2018 11:01 pm
Forum: *Liquid Structure (Viscosity, Surface Tension, Liquid Crystals, Ionic Liquids)
Topic: Shape and Boiling Point
Replies: 10
Views: 305

Re: Shape and Boiling Point

Does the distance between the bonds effect the boiling point? Would this cause the bond to be stronger or weaker? The longer the bond the weaker it is. For instance double bonds are shorter and stronger than single bonds and triple bonds are shorter and stronger than double and single bonds. Yes, a...
by Simran Rai 4E
Mon Nov 05, 2018 3:23 pm
Forum: Administrative Questions and Class Announcements
Topic: MIDTERM PRACTICE - Garlic Bread Review Session [ENDORSED]
Replies: 121
Views: 4713

Re: MIDTERM PRACTICE - Garlic Bread Review Session [ENDORSED]

Hilda Sauceda 3C wrote:Can anyone explain the reasoning for why 6d is true.

6d is true because the answer 10^-11 m is greater 10^-18. If it were less, then wavelength properties wouldn't be measurable.
by Simran Rai 4E
Tue Oct 09, 2018 12:26 am
Forum: Significant Figures
Topic: All students read this sig fig post [ENDORSED]
Replies: 91
Views: 8407

Re: All students read this sig fig post [ENDORSED]

Can someone help me with a quick review of zeros in sig figs? I always get confused as to which zeros count as significant and which ones do not. 1. All non zero numbers are significant. ex) 613 has 3 sig figs 2. Zeros located between non-zero digits are significant ex) 5004 has 4 sig figs 3. Trail...
by Simran Rai 4E
Tue Oct 09, 2018 12:11 am
Forum: SI Units, Unit Conversions
Topic: How does grading for discussion posts work?
Replies: 73
Views: 1836

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 Simran Rai 4E
Tue Oct 09, 2018 12:08 am
Forum: SI Units, Unit Conversions
Topic: How does grading for discussion posts work?
Replies: 73
Views: 1836

Re: How does grading for discussion posts work?

Danny Elias Dis 1E wrote:If we were to post four times in one week, would the extra post roll over to next week's grading?


I don't think it would since the idea is to have 3 engagements weekly rather than finish them all in one week.
by Simran Rai 4E
Wed Oct 03, 2018 5:46 pm
Forum: Limiting Reactant Calculations
Topic: Percent yield
Replies: 10
Views: 191

Re: Percent yield

Actual yield should be given and if it is not then you cannot determine percent yield . The theoretical yield (what you'd calculate) is what would be produced in a perfect reaction with nothing lost (due to heat/ measuring errors/ etc.). The actual yield is usually an experimental value and therefor...
by Simran Rai 4E
Tue Oct 02, 2018 8:10 pm
Forum: Administrative Questions and Class Announcements
Topic: Advice from a Medical Student [ENDORSED]
Replies: 96
Views: 30706

Re: Advice from a Medical Student [ENDORSED]

Thank you so much for this! I'm going into medicine too and hearing your insight made me feel so much better. :)
by Simran Rai 4E
Tue Oct 02, 2018 8:03 pm
Forum: Limiting Reactant Calculations
Topic: Percent yield
Replies: 2
Views: 69

Re: Percent yield

First take the 42.7 g of CaCO3 and convert to moles. 42.7g x (1 mol CaCO3 / 100g CaCO3 ) = 0.4273 mol CaCO3 Then take that and do mole to mole ratio and convert from mols CO2 to grams. .4273 mol CaCO3 x ( 1 mol CO2 / 1 mol CaCO3 ) x ( 44 g CO2 / 1 mol CO2 ) = 18.8 g CO2 Then take your answer and plu...

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