## Search found 76 matches

Sun Mar 18, 2018 2:13 am
Forum: General Science Questions
Topic: Extensive and Intensive
Replies: 1
Views: 277

### Extensive and Intensive

Aside from standard cell potential is there any other intensive things?
Sat Mar 17, 2018 1:32 am
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: wmax
Replies: 4
Views: 323

### wmax

is wmax equal to ΔG° or just ΔG?
Tue Mar 13, 2018 8:19 pm
Forum: Arrhenius Equation, Activation Energies, Catalysts
Topic: arrhenius equation
Replies: 1
Views: 131

### arrhenius equation

when do you use this equation?
Tue Mar 13, 2018 8:18 pm
Forum: Arrhenius Equation, Activation Energies, Catalysts
Topic: arrhenius equation
Replies: 3
Views: 163

### arrhenius equation

when do you use this equation?
Tue Mar 13, 2018 7:42 pm
Forum: Concepts & Calculations Using First Law of Thermodynamics
Topic: Isobaric
Replies: 1
Views: 127

### Isobaric

for an isobaric equation, since delta p = 0, is the internal energy = delta h?
Tue Mar 13, 2018 7:36 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: Bomb Calorimeter
Replies: 2
Views: 280

### Bomb Calorimeter

I made a note that says bomb calorimeter = constant volume, how would you find the internal energy? does constant volume mean delta v = 0?
Mon Mar 12, 2018 11:37 am
Forum: *Alcohols
Topic: functional groups [ENDORSED]
Replies: 4
Views: 554

### functional groups[ENDORSED]

will we need to know functional groups for the final?
Wed Mar 07, 2018 12:50 am
Forum: General Rate Laws
Topic: What equation is this?
Replies: 1
Views: 112

### What equation is this?

what equation is this and when do you use it?

ln (k1/k2) = Ea/R (1/T2 - 1/T1)
Wed Mar 07, 2018 12:48 am
Forum: General Rate Laws
Topic: Rate of Formation/Concentration [ENDORSED]
Replies: 1
Views: 109

### Rate of Formation/Concentration[ENDORSED]

When do you use rate of formation and/or rate of concentration?
Wed Mar 07, 2018 12:34 am
Forum: Zero Order Reactions
Topic: zeroth order rate
Replies: 4
Views: 259

### zeroth order rate

what is the zeroth order rate? is it -k?
Fri Mar 02, 2018 11:16 am
Forum: Arrhenius Equation, Activation Energies, Catalysts
Topic: Arrhenius Reaction
Replies: 6
Views: 219

### Arrhenius Reaction

Did we already go over arrhenius reaction or are we going to?
Wed Feb 28, 2018 10:09 am
Forum: First Order Reactions
Topic: Derivation
Replies: 8
Views: 344

### Derivation

are we going to have to derive or integrate the 1st or 2nd order for test 3 or the final?
Tue Feb 20, 2018 4:51 pm
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: Cell Potential
Replies: 9
Views: 2383

### Cell Potential

when do you use each of the equations and what is the difference?
E = E° -RT/nF * ln Q
E = E° -0.05916 V / n * log Q
Tue Feb 20, 2018 4:46 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Standard cell potential
Replies: 1
Views: 112

### Standard cell potential

when figuring out which reaction to flip so that you get the highest cell potential, do you add or subtract the two cell potentials?
Fri Feb 16, 2018 2:01 am
Forum: Balancing Redox Reactions
Topic: Cl2 and Cl -
Replies: 2
Views: 155

### Cl2 and Cl -

if Cl is just 1- charge how come just making Cl -, 2Cl - doesn't make the charges cancel?
Wed Feb 14, 2018 11:20 am
Forum: Calculating Work of Expansion
Topic: irreversible work [ENDORSED]
Replies: 3
Views: 213

### irreversible work[ENDORSED]

for irreversible expansions, do you use you use w= -p delta v?
Tue Feb 13, 2018 8:57 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: W
Replies: 3
Views: 326

### W

can someone please explain in simple terms and give examples of how to find w for boltzmann equation
Tue Feb 13, 2018 6:50 pm
Forum: Concepts & Calculations Using First Law of Thermodynamics
Topic: PV = nRT
Replies: 6
Views: 300

### PV = nRT

when do you use PV = nRT?
Tue Feb 13, 2018 6:41 pm
Forum: Concepts & Calculations Using First Law of Thermodynamics
Topic: Spontaniety
Replies: 2
Views: 199

### Spontaniety

does being spontaneous have anything to do with speed?
Tue Feb 13, 2018 6:39 pm
Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
Topic: reversible and isothermal
Replies: 1
Views: 142

### reversible and isothermal

if something is reversible and isothermal, i know the total internal energy equals 0, therefore q = -w, but what else should i know about this?
Tue Feb 13, 2018 11:37 am
Forum: Calculating Work of Expansion
Topic: Work
Replies: 1
Views: 122

### Work

For clarification, If a piston compresses does that mean work is positive? And if it expands does that mean work is negative?
Fri Feb 09, 2018 10:52 am
Forum: Gibbs Free Energy Concepts and Calculations
Topic: delta g
Replies: 2
Views: 135

### Re: delta g

delta g r*
Fri Feb 09, 2018 10:51 am
Forum: Gibbs Free Energy Concepts and Calculations
Topic: delta g
Replies: 2
Views: 135

### delta g

what's the difference between delta g, and delta r r, as well as delta g r knot?
Fri Feb 09, 2018 10:40 am
Forum: Administrative Questions and Class Announcements
Topic: Midterm Review Sessions
Replies: 1
Views: 139

### Re: Midterm Review Sessions

Tue Feb 06, 2018 9:21 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: W
Replies: 3
Views: 156

### W

how do you find W?
Tue Feb 06, 2018 8:56 pm
Forum: Concepts & Calculations Using Second Law of Thermodynamics
Topic: Kelvin
Replies: 4
Views: 199

### Kelvin

Do you always have to use kelvin with regards to temperature?
Tue Feb 06, 2018 8:49 pm
Forum: Concepts & Calculations Using Second Law of Thermodynamics
Topic: entropy chnage
Replies: 1
Views: 84

### entropy chnage

in question 9.5 why is it -50 j.k? can someone explain where the negative came from
Tue Feb 06, 2018 8:31 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: monatomic ideal gasses
Replies: 2
Views: 157

### monatomic ideal gasses

what are examples of monatomic ideal gasses?
Mon Feb 05, 2018 11:17 pm
Forum: Entropy Changes Due to Changes in Volume and Temperature
Topic: temperature
Replies: 5
Views: 187

### temperature

for measuring temperature in kelvin on the test do we use 273.15 or just 273?
Mon Jan 29, 2018 2:10 pm
Forum: Gibbs Free Energy Concepts and Calculations
Topic: Spontaneity of a reaction
Replies: 2
Views: 145

### Spontaneity of a reaction

In class we discussed rxn or physical change between the change in s and change in h, Dr. Lavelle mentioned that when delta s is negative and delta h is positive it is never spontaneous but the reverse is. does this mean that the reverse of the other 3 would not be spontaneous?
Tue Jan 23, 2018 11:52 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: calorie and Calorie
Replies: 2
Views: 128

### Re: calorie and Calorie

What is 1 calorie?
Tue Jan 23, 2018 11:22 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Bond Enthalpies
Replies: 4
Views: 177

### Bond Enthalpies

Is bond enthalpies the sum of reactions minus the sum of products or the sum of products minus the sum of reactants?
Tue Jan 23, 2018 11:15 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: calorie and Calorie
Replies: 2
Views: 128

### calorie and Calorie

do we need to know the conversions for calorie and Calorie or will they be provided?
Tue Jan 23, 2018 9:56 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: mass in q = m(c) delta t
Replies: 5
Views: 434

### mass in q = m(c) delta t

when must you covert the g to moles when using the equation for specific heat?
Mon Jan 22, 2018 11:46 pm
Forum: Administrative Questions and Class Announcements
Topic: Week 3 Test Topic is endorsed
Replies: 37
Views: 2053

### Re: Week 3 Test Topic is endorsed

will internal energy be on the test?
Fri Jan 19, 2018 1:51 am
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Enthalpy at constant pressure and volume [ENDORSED]
Replies: 3
Views: 136

### Enthalpy at constant pressure and volume[ENDORSED]

with regards to enthalpy, are we expeced to be able to calculate the heat released at a constant volume or pressure? also what is this 5/2R and 3/2 R business?
Fri Jan 19, 2018 1:37 am
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: Heat Capcity for Water
Replies: 8
Views: 298

### Heat Capcity for Water

How do you know which heat capacity to use for water?
Fri Jan 19, 2018 1:09 am
Forum: Thermodynamic Systems (Open, Closed, Isolated)
Topic: Internal Energy/Open System
Replies: 2
Views: 135

### Internal Energy/Open System

What are the three ways you can increase the internal energy of an open system?
Fri Jan 19, 2018 1:09 am
Forum: Thermodynamic Systems (Open, Closed, Isolated)
Topic: Internal Energy/Open System
Replies: 4
Views: 222

### Internal Energy/Open System

What are the three ways you can increase the internal energy of an open system?
Wed Jan 17, 2018 10:59 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Bond Breaking or forming
Replies: 5
Views: 191

### Re: Bond Breaking or forming

yeah that makes sense, so my follow up question would be after drawing the electron configurations how could you tell if a bond is broken or formed like what would it look like?
Wed Jan 17, 2018 10:22 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Bond Breaking or forming
Replies: 5
Views: 191

### Bond Breaking or forming

When looking at a rxn, is there another way aside from looking at the delta h to know if a bond is forming or breaking?
Wed Jan 17, 2018 10:19 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: Cm
Replies: 3
Views: 173

### Cm

what is Cm in the equation q = n (delta t) (Cm)?
Sun Jan 14, 2018 4:31 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: q and w
Replies: 5
Views: 218

### Re: q and w

soooo my follow up question would be when do you know when work is done on a system vs done by a system?
Sun Jan 14, 2018 4:23 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Bond and Standard Formation Enthalpies
Replies: 1
Views: 89

### Bond and Standard Formation Enthalpies

with bond enthalpies and standard formation enthalpies, i know they're are equations you must follow, what are they and what is each part of the equation?
Sun Jan 14, 2018 4:22 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: q and w
Replies: 5
Views: 218

### q and w

can someone clarify what q and w are as well as how can you tell if they will be positive or negative?
Sun Jan 14, 2018 4:17 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Bond Enthalpies and the use of kJ
Replies: 1
Views: 106

### Bond Enthalpies and the use of kJ

When do you use kJ.mol, kj. Cº or just kj?
Sun Dec 10, 2017 12:22 am
Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
Topic: Calculating pH from pka
Replies: 3
Views: 268

### Re: Calculating pH from pka

like if it asks for the ph but gives you the pka how do you find ph?
Sun Dec 10, 2017 12:21 am
Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
Topic: Calculating pH from pka
Replies: 3
Views: 268

### Re: Calculating pH from pka

would you find the negative log of the pka to find your ka?
Sat Dec 09, 2017 11:57 pm
Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
Topic: Calculating pH from pka
Replies: 3
Views: 268

### Calculating pH from pka

If you are given a pka, how do you go about finding the pH?
Sat Dec 09, 2017 2:50 pm
Forum: Properties of Light
Topic: Speed of light wavelength equation [ENDORSED]
Replies: 4
Views: 279

### Speed of light wavelength equation[ENDORSED]

When do you use the c = wavelength x frequency?
Fri Dec 08, 2017 2:03 pm
Forum: Ionic & Covalent Bonds
Topic: Memorization of Electronegativity
Replies: 6
Views: 352

### Memorization of Electronegativity

Do we need to memorize the actual electronegativity chart as far as values or is just knowing the basic trend enough?
Wed Dec 06, 2017 9:18 pm
Forum: Ionic & Covalent Bonds
Topic: ionic character
Replies: 1
Views: 144

### ionic character

what does “ionic character” mean?
Wed Dec 06, 2017 9:17 pm
Forum: Ionic & Covalent Bonds
Topic: polarizing power
Replies: 1
Views: 161

### polarizing power

what does “polarizing power” mean? Also what does “more polarizable ion” mean?
Tue Dec 05, 2017 2:54 pm
Forum: Identifying Acidic & Basic Salts
Topic: HClO2
Replies: 1
Views: 328

### HClO2

For HClO2 why does it prefer the second O to be connected to the Cl instead of making a chain like Cl-O-O-H?
Tue Dec 05, 2017 1:04 am
Forum: Conjugate Acids & Bases
Topic: Acids and Bases [ENDORSED]
Replies: 8
Views: 593

### Re: Acids and Bases[ENDORSED]

I honestly don't know, but I doubt it. I was told to memorize them by my plf. There's also a list of strong bases. LiOH, NaOH, KOH, RbOH, CsOH, Ca(OH)2, Sr(OH)2, and Ba(OH)2
Tue Dec 05, 2017 12:50 am
Forum: Conjugate Acids & Bases
Topic: Acids and Bases [ENDORSED]
Replies: 8
Views: 593

### Re: Acids and Bases[ENDORSED]

there is a list of strong acids, if it is not one of those, it is considered weak. the list of strong acids include HCl, HBr, HI, HNO3, HClO3, HClO4, H2SO4
Mon Nov 27, 2017 5:07 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: Backward Reaction
Replies: 2
Views: 317

### Backward Reaction

When do you know the reaction is going backwards instead of forwards ?
Mon Nov 27, 2017 2:17 pm
Forum: Student Social/Study Group
Topic: Post All Chemistry Jokes Here
Replies: 7741
Views: 1060210

### Re: Post All Chemistry Jokes Here

What is your LiFe composed of?

-Lithium and iron
Thu Nov 23, 2017 1:29 pm
Forum: Hybridization
Topic: Pi Bonds vs. Sigma Bonds
Replies: 7
Views: 385

### Re: Pi Bonds vs. Sigma Bonds

a single bond has a sigma bond, a double bond has a sigma bond and a pi bond, and a triple bond has a sigma bond and 2 pi bonds
Mon Nov 20, 2017 1:29 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Lewis structure and Vsper
Replies: 2
Views: 148

### Lewis structure and Vsper

when drawing a lewis structure if we know the molecular shape of it from vsper do we draw it accordingly? or are we allowed to place the bonds andywhere around the central atom?
Sat Nov 18, 2017 11:23 am
Forum: Administrative Questions and Class Announcements
Topic: Homework [ENDORSED]
Replies: 1
Views: 170

### Homework[ENDORSED]

Are we allowed to do chapter 4 for homework due next week or do we do chapter 17?
Wed Nov 15, 2017 12:19 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Regions of electron density
Replies: 4
Views: 258

### Regions of electron density

Does a lone pair count as a region of e-density when determining the shape?
Thu Nov 09, 2017 12:40 am
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Replies: 3
Views: 4327

What is the significance/origin of the negative sign in Bohr's equation: En=-hR/n^2
Wed Nov 08, 2017 11:39 pm
Forum: Lewis Structures
Topic: Exceptions
Replies: 4
Views: 264

### Re: Exceptions

chromium and copper
Wed Nov 08, 2017 11:29 pm
Forum: Ionic & Covalent Bonds
Topic: Polar vs. Non-polar
Replies: 7
Views: 391

### Polar vs. Non-polar

How can you tell if a compound is polar or non polar?
Mon Nov 06, 2017 8:29 am
Forum: Trends in The Periodic Table
Topic: Electron Affinity [ENDORSED]
Replies: 6
Views: 511

### Re: Electron Affinity[ENDORSED]

Michael Cheng 1B wrote:What is the difference between electron affinity and electronegativity?

Electronegativity is how well an atom can attract electrons, while electron affinity is how much energy an atom releases when an electron is added.They both share the trend of increasing from bottom to top and left to right.
Mon Nov 06, 2017 8:18 am
Forum: Administrative Questions and Class Announcements
Topic: Homework for this week [ENDORSED]
Replies: 2
Views: 205

### Homework for this week[ENDORSED]

Is the homework for this week chapter 3 or 4?
Thu Nov 02, 2017 1:37 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Orbitals
Replies: 1
Views: 107

### Re: Orbitals

the l value is n-1, what you are talking about is ml, and it is -l to +l
Wed Nov 01, 2017 11:32 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Unpaired Electrons [ENDORSED]
Replies: 3
Views: 304

### Re: Unpaired Electrons[ENDORSED]

you would need to know how many total electrons there are in the atom, what is the last subshell being used, and how many electrons can that subshell hold. Then in the last subshell, you put one arrow in each of the orbitals and then come back around to fill them. for example, if it was oxygen, ther...
Wed Nov 01, 2017 11:19 pm
Forum: Trends in The Periodic Table
Topic: Trends in the periodic table
Replies: 3
Views: 228

### Re: Trends in the periodic table

electron affinity increases from left to right and increases from bottom to top, thereby making fluorine the most electron affinitive. (if that's a word)
Wed Oct 25, 2017 4:21 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Electron Configuration writing
Replies: 8
Views: 403

### Re: Electron Configuration writing

When dealing with an atom that is an ion for example S^2- is it incorrect to write it in condensed from as [Ar]?
Wed Oct 25, 2017 12:36 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Electron Configuration writing
Replies: 8
Views: 403

### Re: Electron Configuration writing

Yesterday we were trying to write rhodium’s electron configuration and we got 2 different answers, so then we looked at the lavelle periodic table and clarified which one is correct, so for clarification, is rhodium an exception like cooper and chromium?
Mon Oct 23, 2017 12:08 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Electronic Configuration for d-block elements [ENDORSED]
Replies: 9
Views: 626

### Re: Electronic Configuration for d-block elements[ENDORSED]

So for elements after 20 would you fill up the 4s and then return back to 3d or fill up 3D and then proceed?
Mon Oct 16, 2017 3:07 pm
Forum: Properties of Light
Topic: Quiz #2 References [ENDORSED]
Replies: 4
Views: 273

### Re: Quiz #2 References[ENDORSED]

Do we have to print out the reference sheet ourselves or will it be given in class?
Thu Oct 05, 2017 1:14 am
Forum: SI Units, Unit Conversions
Topic: Sig Figs
Replies: 12
Views: 819

### Re: Sig Figs

If it was .5060 and you wrote it in scientific notation, It would be 5.060 x 10^-1 so would there be 3 or 4 sig figs?
Thu Oct 05, 2017 1:10 am
Forum: SI Units, Unit Conversions
Topic: Limiting Reagents [ENDORSED]
Replies: 8
Views: 586

### Re: Limiting Reagents[ENDORSED]

It could also ask instead of limiting reactant, which one is the excess and how much excess is there? Or it could ask how many moles can be produced?