Search found 180 matches

by 805097738
Sat Mar 14, 2020 10:27 am
Forum: Arrhenius Equation, Activation Energies, Catalysts
Topic: Elementary Steps
Replies: 4
Views: 13

Re: Elementary Steps

what even are elementary steps
by 805097738
Sat Mar 14, 2020 10:27 am
Forum: Arrhenius Equation, Activation Energies, Catalysts
Topic: Activated Complex vs Transition State
Replies: 5
Views: 22

Re: Activated Complex vs Transition State

805307623 wrote:Activated Complex- collection of intermediate molecules that are created as a chemical reaction progresses
Transition state- intermediate of a chemical reaction that makes up the highest potential energy


When do we use these concepts in the material that we have learned and will be tested on?
by 805097738
Sat Mar 14, 2020 10:25 am
Forum: Arrhenius Equation, Activation Energies, Catalysts
Topic: Catalyst's effect on overall reaction
Replies: 7
Views: 38

Re: Catalyst's effect on overall reaction

jisulee1C wrote:since the slow step is the rate determining step, changing the activation energy of an already fast step will not change the rate because it is not changing the rate of the slow step


how do you determine the fast and slow step?
by 805097738
Wed Mar 11, 2020 8:29 pm
Forum: Administrative Questions and Class Announcements
Topic: final
Replies: 14
Views: 149

Re: final

we're all on standby until he updates us
by 805097738
Mon Mar 09, 2020 6:07 pm
Forum: Arrhenius Equation, Activation Energies, Catalysts
Topic: Catalysts
Replies: 16
Views: 466

Re: Catalysts

AnnaYan_1l wrote:Catalysts reduce the activation energy between reactants to products, meaning it takes less energy to make the forward reaction occur


does this affect the reverse reaction too?
by 805097738
Mon Mar 09, 2020 6:03 pm
Forum: Arrhenius Equation, Activation Energies, Catalysts
Topic: Catalyst vs Intermediate
Replies: 6
Views: 20048

Re: Catalyst vs Intermediate

Kayla Denton 1A wrote:Catalysts are present as reactants in the very beginning and products at the end. Intermediates, on the other hand, are not present in the initial reaction but are produced within one of the steps and then consumed within another step.


a catalyst is one of the reactants?
by 805097738
Mon Mar 09, 2020 5:55 pm
Forum: Reaction Mechanisms, Reaction Profiles
Topic: steady state v preeq
Replies: 4
Views: 28

Re: steady state v preeq

Jiyoon_Hwang_2I wrote:For steady state, the first step of the reaction must be slower than the second step. On the other hand, for pre-equilibrium, the first step must be faster than the second step.


how do you know which step is the fast step and which is the slow step
by 805097738
Mon Mar 09, 2020 5:52 pm
Forum: Reaction Mechanisms, Reaction Profiles
Topic: k'
Replies: 6
Views: 33

Re: k'

Alexis Webb 2B wrote:k' is the rate constant for the reverse reaction.


is this just the reciprocal of the forward reaction?
by 805097738
Mon Mar 09, 2020 5:51 pm
Forum: General Rate Laws
Topic: First vs Second vs Zero Order
Replies: 7
Views: 29

Re: First vs Second vs Zero Order

they all have different relationships with time and therefore produce different graphs.
by 805097738
Mon Mar 09, 2020 5:48 pm
Forum: General Rate Laws
Topic: overall order
Replies: 5
Views: 15

Re: overall order

the overall order is equal to the sum of all the orders of the reactants. The order of each reactant is the exponential value of the reactant
by 805097738
Sun Mar 08, 2020 1:12 pm
Forum: Zero Order Reactions
Topic: third order
Replies: 11
Views: 394

Re: third order

Gillian Ward 1F wrote:Possibly, it is in the curriculum.


what is the third order?
by 805097738
Sun Mar 08, 2020 1:10 pm
Forum: Kinetics vs. Thermodynamics Controlling a Reaction
Topic: Study Advice
Replies: 73
Views: 3488

Re: Study Advice

I personally recommend the online sapling learning problems. The review sessions are great but I've noticed the sapling learning problems are more in line with the test material and you can work at your own pace. Also the site provides very in depth explanations about each problem which I find very ...
by 805097738
Thu Mar 05, 2020 8:58 pm
Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
Topic: lnQ vs logQ
Replies: 5
Views: 56

Re: lnQ vs logQ

When would you use E=E°-(RT/nF)lnQ vs E=E°-(0.05916V/n)logQ ? Also, I understand that you can substitute RT/F for 0.025963 for the ln equation when its under standard condition - 25 degree celsius. Is this correct? Yes, also I use the log one when dealing with H+ or OH- concentration; however, both...
by 805097738
Mon Mar 02, 2020 10:09 pm
Forum: Balancing Redox Reactions
Topic: Acidic vs. Basic Solutions
Replies: 8
Views: 71

Re: Acidic vs. Basic Solutions

if it is in acidic solution you use H+ to balance out the equation and if it is in basic solution you use OH-
by 805097738
Mon Mar 02, 2020 4:47 pm
Forum: Method of Initial Rates (To Determine n and k)
Topic: determine n
Replies: 16
Views: 469

Re: determine n

Alison Trinh 1E wrote:n represents the order of the reactant, which in turn gives insight into the mechanism of the reaction.


how do you know what the order is
by 805097738
Mon Mar 02, 2020 4:47 pm
Forum: Method of Initial Rates (To Determine n and k)
Topic: determine n
Replies: 16
Views: 469

Re: determine n

Samantha Silva 1F wrote:The number of moles.


moles of what?
by 805097738
Mon Mar 02, 2020 4:46 pm
Forum: Method of Initial Rates (To Determine n and k)
Topic: Order
Replies: 5
Views: 51

Re: Order

Vicki Liu 2L wrote:Reaction order is essentially the power to which a reactant concentration is raised in order to give an accurate relationship between it and the rate of the overall reaction.


how do you find this number
by 805097738
Mon Mar 02, 2020 4:45 pm
Forum: General Rate Laws
Topic: Order
Replies: 5
Views: 53

Re: Order

You can look at the reactions graph. Which ever graph produces a straight line will give you the reaction order. For zero order the graph would be (A) v time and would give a straight line with a -slope. First order reaction would be ln(A) v time and would give a straight line with a -slope. Second...
by 805097738
Mon Mar 02, 2020 4:43 pm
Forum: Kinetics vs. Thermodynamics Controlling a Reaction
Topic: instantaneous rate
Replies: 16
Views: 111

Re: instantaneous rate

Because it gives the exact slope at a specific time rather than an average of slopes over a range of t values
by 805097738
Sat Feb 29, 2020 12:00 pm
Forum: Van't Hoff Equation
Topic: HW 11.83
Replies: 4
Views: 598

Re: HW 11.83

Eesha Chattopadhyay 2K wrote:Can we also use the ln(k2/k1)=-delta H standard/R[1/t1 -1/t2] to solve this problem or do we have to find the separate standard G to find the values of K?


the question says to use data in the appendix so I'd find the standard G to find K values
by 805097738
Sat Feb 29, 2020 11:57 am
Forum: Van't Hoff Equation
Topic: Derive [ENDORSED]
Replies: 4
Views: 81

Re: Derive [ENDORSED]

WYacob_2C wrote:How can you derive ln(K1/K2)= -delta H/R (1/T1 - 1/T2) from the Van't Hoff equation given on the formula sheet: lnK=-delta H/RT + delta S/R ? Thank you in advance.


it honestly would probably be easier to just memorize it than try deriving it during the test
by 805097738
Tue Feb 25, 2020 5:40 pm
Forum: Van't Hoff Equation
Topic: Van’t Hoff Equation
Replies: 11
Views: 118

Re: Van’t Hoff Equation

kristi le 2F wrote:The vant hoff equation can be used to calculate K at different temperatures if stand enthalpy of real lion is known.


what is real lion
by 805097738
Tue Feb 25, 2020 5:38 pm
Forum: Van't Hoff Equation
Topic: Converting K back to Kc
Replies: 5
Views: 59

Re: Converting K back to Kc

kennedyp wrote:What's the equation needed to convert K back to Kc? I assumed you would just rearrange the Kc to K equation, but I wanted to ask just to be sure.


aren't those the same
by 805097738
Mon Feb 24, 2020 4:19 pm
Forum: Van't Hoff Equation
Topic: Van't Hoff Equation
Replies: 7
Views: 80

Re: Van't Hoff Equation

TarynD_1I wrote:I think we use Van't Hoff when trying to calculate how K is affected by a change in temperature


yes this is correct as we have a K1 and K2 and a T1 and T2
by 805097738
Mon Feb 24, 2020 4:18 pm
Forum: Van't Hoff Equation
Topic: deltaS/R
Replies: 7
Views: 70

Re: deltaS/R

they aren't ignored, the just get cancelled out when deriving the new equation
by 805097738
Mon Feb 24, 2020 4:10 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Positive and negative standard potential
Replies: 3
Views: 34

Re: Positive and negative standard potential

Brian_Ho_2B wrote:Substances with a higher, positive standard reduction potentials are not able to reduce H+ to H2, while substances with lower, negative reduction potentials can reduce H+ to H2.


why would the substance with a higher reduction potential has less potential to reduce H+? Sounds counter intuitive
by 805097738
Mon Feb 24, 2020 4:07 pm
Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
Topic: Nernst
Replies: 7
Views: 59

Re: Nernst

DesireBrown1J wrote:Why is n moles of electrons transferred instead of the number of electrons transferred? How do we convert it into moles if they are electrons?


They are the same. The number of electrons is the moles of electrons.
by 805097738
Mon Feb 24, 2020 2:37 pm
Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
Topic: Usage for Nernst equation
Replies: 7
Views: 55

Re: Usage for Nernst equation

Kate Osborne 1H wrote:standard conditions are a specific ratio of products to reactants and if the ratio is not that then you have to use the nernst equation


are you referring to K? what else would a specific ratio be
by 805097738
Mon Feb 24, 2020 2:35 pm
Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
Topic: Electrode Potential
Replies: 4
Views: 37

Re: Electrode Potential

the reduction potential. Once you determine which half reaction is oxidized, you change the sign of this potential.
by 805097738
Mon Feb 24, 2020 2:32 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Electromotive Force
Replies: 3
Views: 33

Re: Electromotive Force

the electromotive force is Ecell, the max potential when very little current is flowing. When there is no current flowing, that is when the difference is at its maximum. I thought electromotive force was the max potential of the cell before any current flow? How do you determine "little curren...
by 805097738
Mon Feb 24, 2020 2:27 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Salt bridge
Replies: 6
Views: 45

Re: Salt bridge

charleejohnson1L wrote:The salt bridge keeps the two solutions neutral so the systems can exchange electrons. I hope this helps :)


it allows for the flow of ions as well
by 805097738
Sun Feb 23, 2020 4:26 pm
Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
Topic: 6N.3
Replies: 6
Views: 80

Re: 6N.3

805291863 wrote:Also, how is the n value determined here?


n value is determined by the moles of electrons in each of the balanced half rxn equations
by 805097738
Thu Feb 20, 2020 12:53 pm
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: Answer is different for 5G.15
Replies: 5
Views: 47

Re: Answer is different for 5G.15

KeyaV1C wrote:I got -27 kJ/mol as my answer.


how did you get this??
by 805097738
Wed Feb 19, 2020 7:42 pm
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: Answer is different for 5G.15
Replies: 5
Views: 47

Re: Answer is different for 5G.15

I keep getting -2.7 kJ as well. Can someone explain what we are doing wrong?
by 805097738
Wed Feb 19, 2020 7:12 pm
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: 6N1 part b
Replies: 1
Views: 25

6N1 part b

if the reduction half of the rxn goes from In3+ to In2+, why does the answer key say that 2 electrons are added to In3+ to get to In2+. Why is it not 1 electron???
by 805097738
Tue Feb 18, 2020 6:38 pm
Forum: Balancing Redox Reactions
Topic: Understanding Half-Reactions
Replies: 11
Views: 78

Re: Understanding Half-Reactions

half reactions let us understand what is happening exactly to the molecule being reduced and same for the molecule being oxidized. Each reaction on their own has cell potential measured in volts; so, by looking at both measures, we can add them together to get the cell potential as a whole. But ove...
by 805097738
Tue Feb 18, 2020 6:38 pm
Forum: Balancing Redox Reactions
Topic: Understanding Half-Reactions
Replies: 11
Views: 78

Re: Understanding Half-Reactions

half reactions let us understand what is happening exactly to the molecule being reduced and same for the molecule being oxidized. Each reaction on their own has energy potential measured in volts; so, by looking at both measures, we can add them together to get the energy potential as a whole. But ...
by 805097738
Tue Feb 18, 2020 6:34 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Electrochemical cell
Replies: 4
Views: 50

Re: Electrochemical cell

So this redox reaction occurs within a single cell?
by 805097738
Tue Feb 18, 2020 6:32 pm
Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
Topic: Ecell
Replies: 5
Views: 259

Re: Ecell

what is the difference between Ecell and Eocell?
by 805097738
Tue Feb 18, 2020 6:30 pm
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: n in -nFE
Replies: 14
Views: 171

Re: n in -nFE

n represents the number of electrons transferred in this equation!
by 805097738
Sun Feb 16, 2020 8:24 pm
Forum: Balancing Redox Reactions
Topic: Oxidation Number
Replies: 2
Views: 26

Oxidation Number

How are we supposed to know the oxidation number for each element in a compound?
by 805097738
Sun Feb 16, 2020 4:45 pm
Forum: Balancing Redox Reactions
Topic: oxidation vs reduction
Replies: 19
Views: 132

Re: oxidation vs reduction

if the compound is oxidized, it will lose electrons. And if it is reduced, it will gain electrons. You can determine which process the compound undergoes by looking at its change in charge.
by 805097738
Sun Feb 16, 2020 4:43 pm
Forum: Balancing Redox Reactions
Topic: Electrochemisty
Replies: 10
Views: 66

Re: Electrochemisty

it is the study of chemical processes that cause electrons to move, resulting in electricity that is generated by the movements of electrons from one element to another. This reaction is known as a redox reaction and is important because we will be doing many redox reaction problems in electrochemis...
by 805097738
Tue Feb 11, 2020 9:53 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: degeneracy W
Replies: 7
Views: 67

Re: degeneracy W

Ryan Lee 1E wrote:Na is going to be Avogadro's number whereas lowercase n is going to be the number of moles.


When do we use Avogadro's number instead of moles?
by 805097738
Tue Feb 11, 2020 9:52 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: Residual Entropy
Replies: 6
Views: 71

Re: Residual Entropy

DarrenKim_3G wrote:residual entropy is the remaining entropy left in molecules at 0 K


what does that mean? and when will we use this?
by 805097738
Tue Feb 11, 2020 9:51 pm
Forum: Concepts & Calculations Using Second Law of Thermodynamics
Topic: Cv vs. Cp?
Replies: 3
Views: 32

Re: Cv vs. Cp?

if there is both a change in volume and temperature you do two separate calculations for each using the proper C respectively and then add the two together
by 805097738
Tue Feb 11, 2020 9:49 pm
Forum: Concepts & Calculations Using First Law of Thermodynamics
Topic: Delta U
Replies: 8
Views: 77

Re: Delta U

this is the internal energy of the system. so w would be the work either done by or on the system and q would be the heat either absorbed or given off by the system. the changes are looked at in the perspective of the system
by 805097738
Tue Feb 11, 2020 9:47 pm
Forum: Calculating Work of Expansion
Topic: Midterm equation sheet
Replies: 16
Views: 136

Re: Midterm equation sheet

yes, it is the same one
by 805097738
Sat Feb 08, 2020 3:40 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Units for heat of reaction
Replies: 9
Views: 61

Re: Units for heat of reaction

do you have to explicitly state per mole or is that implied already
by 805097738
Thu Feb 06, 2020 12:31 pm
Forum: Phase Changes & Related Calculations
Topic: about system and surroundings
Replies: 8
Views: 57

Re: about system and surroundings

so the surrounding is the universe?
by 805097738
Tue Feb 04, 2020 1:03 pm
Forum: Concepts & Calculations Using Second Law of Thermodynamics
Topic: negative entropy
Replies: 4
Views: 27

Re: negative entropy

Lauren Tanaka 1A wrote:Negative entropy is possible and just means that there is an overall decrease in entropy for the given system.


what does decrease in entropy mean for the system though
by 805097738
Tue Feb 04, 2020 1:03 pm
Forum: Concepts & Calculations Using Second Law of Thermodynamics
Topic: negative entropy
Replies: 4
Views: 27

Re: negative entropy

eduardomorales5 wrote:Negative entropy means there is a decrease in the disorder of the system or increase in the order of the system.


how is it both?
by 805097738
Tue Feb 04, 2020 1:02 pm
Forum: Thermodynamic Systems (Open, Closed, Isolated)
Topic: Isolated systems
Replies: 4
Views: 31

Re: Isolated systems

Mitchell Koss 4G wrote:Closed is like a test tube with a cap on it, so solution can be heated or lose heat.
Isolated is behind thick walls like a bomb calorimeter or thermos so no outside interaction can occur.


how do we determine which one it is, or will it be stated?
by 805097738
Tue Feb 04, 2020 1:01 pm
Forum: Concepts & Calculations Using First Law of Thermodynamics
Topic: q and w
Replies: 10
Views: 83

Re: q and w

Nawal Dandachi 1G wrote:q would be positive if heat is being added to the system and negative if heat is being removed. w would be positive if work is done by the system and negative if work is done on the system.


what is an example of work being done on or to the system?
by 805097738
Tue Feb 04, 2020 12:59 pm
Forum: Calculating Work of Expansion
Topic: when to use...?
Replies: 4
Views: 40

Re: when to use...?

ALegala_2I wrote:You use w=-PV when there is an expansion occurring at a constant external pressure. You use the other equation when there is a change in internal and external pressure for expansion work.


what is the other equation?
by 805097738
Mon Feb 03, 2020 3:37 pm
Forum: Phase Changes & Related Calculations
Topic: Calorimeters
Replies: 8
Views: 47

Re: Calorimeters

how many types are there?
by 805097738
Wed Jan 29, 2020 1:02 pm
Forum: Thermodynamic Systems (Open, Closed, Isolated)
Topic: System vs Surroundings
Replies: 14
Views: 433

Re: System vs Surroundings

Yes, the system vs. surrounding should not be something you have to memorize. As mentioned before, the system is simply the situation in question, such as a piston. Since the first law of thermodynamics states the conservation of energy, a change in energy of the system means a resultant change in ...
by 805097738
Wed Jan 29, 2020 12:56 pm
Forum: Thermodynamic Systems (Open, Closed, Isolated)
Topic: Systems at equilibrium
Replies: 3
Views: 40

Re: Systems at equilibrium

We will discuss it more when we start talking about thermodynamics. For now, all we need to know is that there is a difference in the amount of work done depending on whether the gaseous system is under pressure or not. what is this difference? Is this just a concept we have to know or are their fo...
by 805097738
Mon Jan 27, 2020 12:57 pm
Forum: Phase Changes & Related Calculations
Topic: ∆H
Replies: 17
Views: 98

Re: ∆H

MingdaH 3B wrote:No, you can touch it.


wait what this a serious response lol
by 805097738
Mon Jan 27, 2020 12:41 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Methods to Calculate Enthalpies
Replies: 6
Views: 48

Re: Methods to Calculate Enthalpies

Brian J Cheng 1I wrote:Depends on the information given and the setup of the question. For example: if multiple rxn equations are given with their respective enthalpy changes, then you might suspect Hess's Law. If bond energies are given, then you might use bond energies.


what exactly are bond energies?
by 805097738
Mon Jan 27, 2020 12:39 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: pressure and enthalpy
Replies: 5
Views: 39

Re: pressure and enthalpy

Why does enthalpy increase as temperature increases?
by 805097738
Mon Jan 27, 2020 12:38 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: q=mCdeltaT
Replies: 15
Views: 2915

Re: q=mCdeltaT

if the equation uses the g variable then use grams. If it uses the m variable which is usually represented by n, use number of moles.
by 805097738
Mon Jan 27, 2020 12:33 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: bomb calorimeter
Replies: 5
Views: 31

Re: bomb calorimeter

it measures heat of a system with CV (the volume is fixed so pressure is not constant)
by 805097738
Mon Jan 27, 2020 12:30 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: Extensive vs intensive propeties
Replies: 5
Views: 27

Re: Extensive vs intensive propeties

well,heat capacity is an extensive property because it depends on the amount of substance. If we divide the heat capacity by the amount of substance, it becomes an intensive property.
by 805097738
Mon Jan 27, 2020 12:27 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Signs for enthalpy
Replies: 8
Views: 40

Re: Signs for enthalpy

the sign of enthalpy indicates if the reaction is endothermic (positive) or exothermic (negative)
by 805097738
Sun Jan 26, 2020 2:03 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Exothermic reaction
Replies: 18
Views: 85

Re: Exothermic reaction

in an exothermic reaction if temp is decreased the rxn will move forward as it is a "product" (is released)
by 805097738
Thu Jan 23, 2020 12:54 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: H20 in the ICE table
Replies: 26
Views: 152

Re: H20 in the ICE table

you leave out any molecule that is a pure liquid or solid. If H20 is in a gas phase, then it is included
by 805097738
Wed Jan 22, 2020 12:28 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: pKa and pKb
Replies: 17
Views: 119

Re: pKa and pKb

pka and pkb are added together to get 14; so, if you know one, you can subtract it from 14 to get the other
by 805097738
Wed Jan 22, 2020 12:26 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: pressure and volume
Replies: 3
Views: 18

Re: pressure and volume

volume and pressure are inversely related. it's easy to answer those questions if you memorize that
by 805097738
Tue Jan 21, 2020 12:55 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: expanding the volume
Replies: 3
Views: 28

Re: expanding the volume

because the pressure is decreased and in order to minimize this change, the reaction reaction move towards the side with more moles so there is more pressure
by 805097738
Mon Jan 20, 2020 12:30 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: pH sig figs
Replies: 5
Views: 55

Re: pH sig figs

One of the UAs said that the amount of sig figs in the problem is the amount of sig figs you place after the decimal for pH
by 805097738
Sun Jan 19, 2020 12:21 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: Q < K
Replies: 16
Views: 79

Re: Q < K

correct that is what that means. forward rxn favors the product
by 805097738
Sun Jan 19, 2020 12:20 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Test 1
Replies: 6
Views: 46

Re: Test 1

just the material from weeks one and two!
by 805097738
Sun Jan 19, 2020 12:18 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: 5% rule
Replies: 10
Views: 77

Re: 5% rule

because the change in x is so small, the original molarity of the molecule being changed by x is a suffice approximation.
by 805097738
Sun Jan 19, 2020 12:17 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Pressure
Replies: 5
Views: 24

Re: Pressure

it goes to the side with less moles.
by 805097738
Sun Jan 19, 2020 12:16 pm
Forum: Ideal Gases
Topic: R Constant
Replies: 7
Views: 35

Re: R Constant

Kimberly Koo 2I wrote:R is the universal gas constant, which is 0.082 L.atm/mol.K


there are different R constants for different units though
by 805097738
Sun Jan 19, 2020 12:14 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: ICE Box
Replies: 4
Views: 22

Re: ICE Box

pure liquids and solids are not involved in the ice box so H20 wouldn't be involved in liquid form. However, it is when it is in gas form like the examples in class.
by 805097738
Sun Jan 19, 2020 12:10 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Different Values for K and Kc?
Replies: 3
Views: 31

Re: Different Values for K and Kc?

that is strange. I thought that K and Kc were the same. The only thing I can think of is if K were calculated in Pressure and than converted to Kc but I didn't do the math to test that. I also don't know why it would be calculated differently.
by 805097738
Thu Jan 16, 2020 1:00 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Autoprolysis
Replies: 9
Views: 61

Re: Autoprolysis

Wendy Perez 1E wrote:Adding to this conversation, what does amphiprotic mean again?


can accept or donate a proton
by 805097738
Thu Jan 16, 2020 12:58 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: How to make ICE box
Replies: 17
Views: 156

Re: How to make ICE box

the moles represent the amount of X that will change. If the molecules go into the eq the change is -, and if the molecules come out of the eq the change is +
by 805097738
Mon Jan 13, 2020 12:51 pm
Forum: Ideal Gases
Topic: Topics for Test 1
Replies: 17
Views: 143

Re: Topics for Test 1

The UA's said the material would cover up to this friday's class material so I would focus of the first two weeks of information. The lecture videos that Lavelle posted cover a lot of the information and have great practice problems!
by 805097738
Mon Jan 13, 2020 12:46 pm
Forum: Ideal Gases
Topic: ICE Table
Replies: 9
Views: 77

Re: ICE Table

You should calculate Q so you know which direction the reaction is moving and then you can identify if the products or reactants are favored to determine if x is positive or negative for each molecule
by 805097738
Mon Jan 13, 2020 12:43 pm
Forum: Ideal Gases
Topic: R constant
Replies: 6
Views: 40

R constant

When do we know when to use which R constant?

What are the two R constants and when are they used?

Is the unit for gas measured in atm pressure or bars?
by 805097738
Mon Jan 13, 2020 12:37 pm
Forum: Ideal Gases
Topic: Understanding Q
Replies: 19
Views: 114

Re: Understanding Q

To solve for Q we have to be given the values of each product and reactant, correct?
by 805097738
Mon Jan 13, 2020 12:34 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: What is this?
Replies: 23
Views: 379

Re: What is this?

This principle tries to minimize the effect of change by shifting the direction of the reaction in order to maintain equilibrium
by 805097738
Mon Jan 13, 2020 12:28 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: Reaction shifts right or left?
Replies: 14
Views: 133

Re: Reaction shifts right or left?

Yes, if the reaction is shifted to the left that means that the are more moles on the left side of the reaction which are the reactants. While if the reaction is shifted to the right that means there are more moles on the right side of the reaction which are the products. if there are more moles on...
by 805097738
Mon Jan 13, 2020 12:24 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: Q=K
Replies: 14
Views: 79

Re: Q=K

Q doesn't have to be strictly not at equilibrium. It can be at any point in the reaction including equilibrium, K.
by 805097738
Mon Jan 13, 2020 12:21 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: PV=nRT
Replies: 9
Views: 53

Re: PV=nRT

have we gone over this in class in an example equation?
by 805097738
Thu Jan 09, 2020 7:06 pm
Forum: Ideal Gases
Topic: Understanding Q
Replies: 19
Views: 114

Re: Understanding Q

do you omit pure solids and liquids while solving for K too?
by 805097738
Thu Jan 09, 2020 6:55 pm
Forum: Ideal Gases
Topic: converting Kc to Kp
Replies: 13
Views: 111

Re: converting Kc to Kp

the volume is already included in the concentration as it is moles over volume
by 805097738
Wed Jan 08, 2020 8:17 pm
Forum: Administrative Questions and Class Announcements
Topic: Sapling Learning
Replies: 9
Views: 76

Sapling Learning

Are the assignments on sapling learning mandatory? And if so, when are they due?
by 805097738
Wed Jan 08, 2020 7:42 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: HW 5I.5
Replies: 3
Views: 48

Re: HW 5I.5

correct it is just a unit
by 805097738
Wed Jan 08, 2020 1:24 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: Effects of Concentration on Equilibrium
Replies: 6
Views: 59

Re: Effects of Concentration on Equilibrium

yes it will be temporarily shifted
by 805097738
Wed Jan 08, 2020 1:19 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: K vs Kp vs Kc
Replies: 9
Views: 65

Re: K vs Kp vs Kc

K is the general term for equilibrium constant. Kp is for reaction involving gases and Kc is for reactions involving aqueous.
by 805097738
Tue Jan 07, 2020 6:24 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Expression for K
Replies: 4
Views: 42

Expression for K

Why d we have to put P in front of the molecules? for example= (P O2) + (P H4)
by 805097738
Mon Jan 06, 2020 7:24 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: 5G.3
Replies: 8
Views: 81

Re: 5G.3

partial pressure is used because the reaction only involves gases
by 805097738
Fri Dec 06, 2019 9:43 pm
Forum: Identifying Acidic & Basic Salts
Topic: deciding whether the solution of a salt is basic, acidic, or neutral
Replies: 5
Views: 68

Re: deciding whether the solution of a salt is basic, acidic, or neutral

If, in the presence of water, a salt gains an H+ (becoming an acid) and produces OH- ions, the solution will be basic. If, in the presence of water, a salt loses an H+ (becoming a base) and produces H+ ions, the solution will be basic. <- you mean acidic??** ex: C2H3O2 (-) (aq) + H2O (l) ---> HC2H3...
by 805097738
Fri Dec 06, 2019 9:39 pm
Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
Topic: Weak vs Strong acids and bases
Replies: 6
Views: 44

Re: Weak vs Strong acids and bases

a weak base will have a lower pH than a strong base

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