Search found 53 matches

by Patricia Macalalag 2E
Wed Mar 14, 2018 6:49 pm
Forum: Thermodynamic Systems (Open, Closed, Isolated)
Topic: The First Law
Replies: 6
Views: 298

Re: The First Law

Yes it's the same
by Patricia Macalalag 2E
Mon Mar 12, 2018 1:59 am
Forum: Arrhenius Equation, Activation Energies, Catalysts
Topic: How does a homogeneous catalyst affect (a) the rate law; (b) the equilibrium constant? [ENDORSED]
Replies: 5
Views: 185

Re: How does a homogeneous catalyst affect (a) the rate law; (b) the equilibrium constant? [ENDORSED]

For part b) isn't the answer no effect? The textbook says catalysts have no effect on the equilibrium composition.
by Patricia Macalalag 2E
Mon Mar 05, 2018 11:45 am
Forum: Kinetics vs. Thermodynamics Controlling a Reaction
Topic: Quiz 3
Replies: 3
Views: 110

Re: Quiz 3

I think it's up to #39, but I'd take a look at the integrated exercises
by Patricia Macalalag 2E
Mon Mar 05, 2018 11:30 am
Forum: General Rate Laws
Topic: zero order in rate laws
Replies: 8
Views: 178

Re: zero order in rate laws

You can leave it out because it has no effect on the rate.
by Patricia Macalalag 2E
Mon Mar 05, 2018 11:22 am
Forum: Zero Order Reactions
Topic: Will we need to know how to derive equations? [ENDORSED]
Replies: 9
Views: 271

Re: Will we need to know how to derive equations? [ENDORSED]

Knowing the derivations can only help you not hurt you!
by Patricia Macalalag 2E
Wed Feb 28, 2018 9:29 pm
Forum: Zero Order Reactions
Topic: Negative order
Replies: 4
Views: 115

Re: Negative order

I looked up negative order and apparently it indicates that the concentration of that species inversely affects the rate of the reaction. I'll link the site below

https://chem.libretexts.org/Core/Physic ... tion_Order
by Patricia Macalalag 2E
Wed Feb 28, 2018 9:20 pm
Forum: Kinetics vs. Thermodynamics Controlling a Reaction
Topic: Homework for Test 3
Replies: 2
Views: 119

Re: Homework for Test 3

We stop after #39 I believe
by Patricia Macalalag 2E
Wed Feb 28, 2018 8:43 pm
Forum: First Order Reactions
Topic: Derivation
Replies: 8
Views: 212

Re: Derivation

My TA said we won't have to do any derivations on the test, but knowing them does help increase understanding of the concepts
by Patricia Macalalag 2E
Tue Feb 27, 2018 10:24 pm
Forum: First Order Reactions
Topic: First Order Reaction Equations
Replies: 3
Views: 94

Re: First Order Reaction Equations

It's the same thing, you should get the same answer.
by Patricia Macalalag 2E
Fri Feb 23, 2018 12:38 am
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Inert Electrodes
Replies: 4
Views: 138

Re: Inert Electrodes

allyz1F wrote:What about for salt bridges too? When do you know to include a salt bridge in the cell diagram and when is it not necessary?


The salt bridge maintains the charges between the anode and cathode so the reaction can happen, but you don't always have to use a salt bridge. Porous disks work as well.
by Patricia Macalalag 2E
Fri Feb 23, 2018 12:35 am
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Cell diagram
Replies: 4
Views: 132

Re: Cell diagram

chem mod posted in another post that electrodes and solids are furthest from the salt bridge, followed by liquids, gases, and aqueous solutions, but most people usually order it reactants to products
by Patricia Macalalag 2E
Fri Feb 23, 2018 12:29 am
Forum: Balancing Redox Reactions
Topic: Finding half reactions
Replies: 4
Views: 169

Re: Finding half reactions

The half reactions are given on the test
by Patricia Macalalag 2E
Fri Feb 16, 2018 8:39 pm
Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
Topic: Work
Replies: 5
Views: 179

Re: Work

Yes, w=0.
by Patricia Macalalag 2E
Fri Feb 16, 2018 8:07 pm
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: Delta G standard
Replies: 4
Views: 139

Re: Delta G standard

Either way is fine
by Patricia Macalalag 2E
Fri Feb 16, 2018 7:59 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Equilibrium
Replies: 4
Views: 78

Re: Equilibrium

The current should stop
by Patricia Macalalag 2E
Tue Feb 06, 2018 10:43 pm
Forum: Third Law of Thermodynamics (For a Unique Ground State (W=1): S -> 0 as T -> 0) and Calculations Using Boltzmann Equation for Entropy
Topic: Boltzmann
Replies: 3
Views: 109

Re: Boltzmann

kb is Boltzmann's constant, and it's given to us in the constants and formulas sheet
by Patricia Macalalag 2E
Tue Feb 06, 2018 10:21 pm
Forum: Concepts & Calculations Using First Law of Thermodynamics
Topic: Test question [ENDORSED]
Replies: 16
Views: 487

Re: Test question [ENDORSED]

They accepted multiple answers. Mine was "energy cannot be created or destroyed; it must be exchanged."
by Patricia Macalalag 2E
Tue Feb 06, 2018 8:31 pm
Forum: Administrative Questions and Class Announcements
Topic: Bruin Cast
Replies: 5
Views: 214

Re: Bruin Cast

No it's not bruincasted
by Patricia Macalalag 2E
Tue Jan 30, 2018 11:36 pm
Forum: Entropy Changes Due to Changes in Volume and Temperature
Topic: 9.3
Replies: 5
Views: 154

Re: 9.3

The signs dictate the flow of energy
by Patricia Macalalag 2E
Tue Jan 30, 2018 10:47 pm
Forum: Entropy Changes Due to Changes in Volume and Temperature
Topic: Homework 9.13
Replies: 2
Views: 89

Re: Homework 9.13

I think it's just to make calculations simpler
by Patricia Macalalag 2E
Tue Jan 30, 2018 10:45 pm
Forum: Student Social/Study Group
Topic: Post All Chemistry Jokes Here
Replies: 7337
Views: 785626

Re: Post All Chemistry Jokes Here

What kind of dogs do chemists have?

Laboratory retrievers
by Patricia Macalalag 2E
Mon Jan 22, 2018 11:59 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Average Kinetic Energy
Replies: 2
Views: 96

Re: Average Kinetic Energy

8.103 is a suggested problem though, so I'd know how to do it
by Patricia Macalalag 2E
Mon Jan 22, 2018 11:54 pm
Forum: Administrative Questions and Class Announcements
Topic: Week 3 Test Topic is endorsed
Replies: 37
Views: 1639

Re: Week 3 Test Topic is endorsed

Lauryn Jordan 1F wrote:will internal energy be on the test?


We won't be required to solve for internal energy, I believe, but there will probably be concept questions on it.
by Patricia Macalalag 2E
Mon Jan 22, 2018 11:46 pm
Forum: Phase Changes & Related Calculations
Topic: Problem 8.43
Replies: 5
Views: 144

Re: Problem 8.43

Gurkriti Ahluwalia 1K wrote:can someone therefore explain why a isn't the correct choice also??


I think A isn't the correct choice either because melting is supposed to occur twice as fast as vaporization. In A, it's the opposite; vaporization occurs twice as fast as melting.
by Patricia Macalalag 2E
Tue Jan 16, 2018 8:26 pm
Forum: Administrative Questions and Class Announcements
Topic: Acids and Bases
Replies: 3
Views: 146

Re: Acids and Bases

I just checked the outlines on the Chem 14B website, and I don't see any acid/base stuff. I could be wrong though.
by Patricia Macalalag 2E
Tue Jan 16, 2018 8:11 pm
Forum: Phase Changes & Related Calculations
Topic: Types of Systems
Replies: 10
Views: 302

Re: Types of Systems

^^I don't think so. The textbook only defines open, closed, and isolated systems.
by Patricia Macalalag 2E
Fri Jan 12, 2018 6:51 pm
Forum: Student Social/Study Group
Topic: Post All Chemistry Jokes Here
Replies: 7337
Views: 785626

Re: Post All Chemistry Jokes Here

I can't tell you any good chemistry jokes because all the good ones argon.
by Patricia Macalalag 2E
Fri Jan 12, 2018 6:16 pm
Forum: Administrative Questions and Class Announcements
Topic: Times to post per week
Replies: 5
Views: 226

Re: Times to post per week

Yes 3 a week, and they don't rollover so you can't make up points.
by Patricia Macalalag 2E
Sun Dec 10, 2017 12:13 am
Forum: Sigma & Pi Bonds
Topic: Delocalization of Pi bonds
Replies: 1
Views: 179

Re: Delocalization of Pi bonds

Delocalized just means that your electrons can move around, so it's associated with resonance structures.
by Patricia Macalalag 2E
Sun Dec 10, 2017 12:11 am
Forum: Lewis Acids & Bases
Topic: Conjugate Acids and Bases
Replies: 1
Views: 134

Re: Conjugate Acids and Bases

Yes; if an acid is strong, it'll have a weak conjugate base. If an acid is weak, it'll have a strong conjugate base.
by Patricia Macalalag 2E
Sun Dec 10, 2017 12:03 am
Forum: Lewis Acids & Bases
Topic: CONJUGATE
Replies: 3
Views: 184

Re: CONJUGATE

Yes
by Patricia Macalalag 2E
Sat Dec 09, 2017 11:25 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Mono/poly Dentates
Replies: 1
Views: 153

Re: Mono/poly Dentates

At one of the review sessions, we were told to just count up the nitrogens!
by Patricia Macalalag 2E
Sat Dec 09, 2017 11:24 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Test 4 #6
Replies: 1
Views: 200

Re: Test 4 #6

When you plug 2.6 into 5-2x, you get a negative value
by Patricia Macalalag 2E
Wed Dec 06, 2017 5:10 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Will we be given Table 11.2?
Replies: 2
Views: 108

Re: Will we be given Table 11.2?

I'm pretty sure we don't have to memorize it.
by Patricia Macalalag 2E
Wed Dec 06, 2017 5:05 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: 11.25 [ENDORSED]
Replies: 2
Views: 116

Re: 11.25 [ENDORSED]

I believe it's because the problem asks for equilibrium concentration, rather than partial pressure. If you look at 11.27, it asks for partial pressure instead, and you would use the notation with "P."
by Patricia Macalalag 2E
Tue Dec 05, 2017 10:35 pm
Forum: Dipole Moments
Topic: Dipole Moments and Polarity
Replies: 9
Views: 306

Re: Dipole Moments and Polarity

It also helps to just remember Fluorine is the most electronegative, so you know elements to the upper right will be very electronegative.
by Patricia Macalalag 2E
Tue Dec 05, 2017 10:07 pm
Forum: Naming
Topic: Nitrogen and Ligands
Replies: 2
Views: 151

Re: Nitrogen and Ligands

Usually, coordination # = # of the bonds linked to the central atom (usually a metal from what we've been doing)
by Patricia Macalalag 2E
Tue Dec 05, 2017 10:04 pm
Forum: Naming
Topic: Determining Linking Atom
Replies: 2
Views: 101

Re: Determining Linking Atom

Isn't it usually the metal?
by Patricia Macalalag 2E
Tue Dec 05, 2017 9:55 pm
Forum: Sigma & Pi Bonds
Topic: Delocalized Pi-Bonding
Replies: 5
Views: 343

Re: Delocalized Pi-Bonding

It is delocalized because the e- can move around, resulting in resonance structures. This is only seen when a pi-bond is present.
by Patricia Macalalag 2E
Tue Dec 05, 2017 9:40 pm
Forum: Coordinate Covalent Bonds
Topic: Naming - Prefixes
Replies: 2
Views: 248

Naming - Prefixes

How do we know when to use the prefixes: bis-, tris-, tetrakis-, etc.?
by Patricia Macalalag 2E
Tue Dec 05, 2017 9:23 pm
Forum: Dipole Moments
Topic: Dipole moments and Formal Charges
Replies: 2
Views: 188

Re: Dipole moments and Formal Charges

I think you're supposed compare the electronegativity of the atoms and their respective arrangement in the shape of the molecule; this should help you determine dipole moments. This in turn should help determine polarity.
by Patricia Macalalag 2E
Tue Dec 05, 2017 9:01 pm
Forum: Dipole Moments
Topic: Dipole Moments and Polarity
Replies: 9
Views: 306

Re: Dipole Moments and Polarity

Aren't we just supposed to analyze the electronegativity trend on the periodic table? It increases as you go left to right, and as you go up a group.
by Patricia Macalalag 2E
Tue Dec 05, 2017 8:41 pm
Forum: Sigma & Pi Bonds
Topic: Double Bond Being Pi+Pi
Replies: 2
Views: 165

Re: Double Bond Being Pi+Pi

^^ Yeah a double bond cannot consist of two pi bonds
by Patricia Macalalag 2E
Tue Dec 05, 2017 8:38 pm
Forum: Photoelectric Effect
Topic: Midterm question [ENDORSED]
Replies: 6
Views: 343

Re: Midterm question [ENDORSED]

@Helen, not necessarily because we don't know if the threshold has been surpassed
by Patricia Macalalag 2E
Tue Dec 05, 2017 8:26 pm
Forum: Student Social/Study Group
Topic: Post All Chemistry Jokes Here
Replies: 7337
Views: 785626

Re: Post All Chemistry Jokes Here

I'm female.

Fe = Iron
Male = man

Therefore, I am Iron Man.
by Patricia Macalalag 2E
Tue Dec 05, 2017 8:22 pm
Forum: Student Social/Study Group
Topic: Post All Chemistry Jokes Here
Replies: 7337
Views: 785626

Re: Post All Chemistry Jokes Here

Don't get chemists angry, they overreact.
by Patricia Macalalag 2E
Tue Dec 05, 2017 8:20 pm
Forum: Student Social/Study Group
Topic: Post All Chemistry Jokes Here
Replies: 7337
Views: 785626

Re: Post All Chemistry Jokes Here

What's the formula for seawater?

CH20
by Patricia Macalalag 2E
Fri Oct 20, 2017 11:39 pm
Forum: Properties of Light
Topic: Planck's Constant
Replies: 10
Views: 418

Re: Planck's Constant

Don't forget that the units for Planck's Constant are joules times seconds!
by Patricia Macalalag 2E
Wed Oct 18, 2017 9:48 pm
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: Atomic Spectra Module Q28
Replies: 2
Views: 159

Atomic Spectra Module Q28

How would you approach this problem from the modules? The meter was defined in 1963 as 1,650,763.73 wavelengths of radiation emitted by krypton-86 (it has since been redefined). What is the wavelength of this krypton-86 radiation? To what region of the electromagnetic spectrum does this wavelength c...

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