## Search found 31 matches

Sat Mar 16, 2019 10:11 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Stability of reactants and products
Replies: 2
Views: 278

### Stability of reactants and products

How do you determine the relative stability of reactants and products?
Tue Mar 12, 2019 6:59 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Partial Pressure to Concentration
Replies: 3
Views: 119

### Partial Pressure to Concentration

How do we convert the partial pressure to concentration?
Mon Mar 11, 2019 10:55 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Ka/b and pKa/b relationship
Replies: 2
Views: 88

### Ka/b and pKa/b relationship

What is the relationship between Ka and pKb? Does pKb go down if Ka goes up? Also, what pKa and Ka produce a strong conjugate base?
Wed Mar 06, 2019 10:18 pm
Forum: Reaction Mechanisms, Reaction Profiles
Topic: Rate-Controlling Step
Replies: 3
Views: 134

### Rate-Controlling Step

Are the slow steps always the rate controlling steps? Either way, why does the rate controlling step have its significance as the controlling step?
Wed Mar 06, 2019 10:03 pm
Forum: Reaction Mechanisms, Reaction Profiles
Topic: Reaction Intermediates
Replies: 4
Views: 159

### Reaction Intermediates

How do we figure out what are the reaction intermediates? For example, in question 7C.3:
Step 1 - $AC+B\rightarrow AB+C$
Step 2 - $AC+AB\rightarrow A_{2}B+C$

How do we know that the intermediate is AB?
Wed Mar 06, 2019 9:51 pm
Forum: General Rate Laws
Topic: Example 7C.1
Replies: 1
Views: 81

### Example 7C.1

Given the chemical equation 2O_{3}\rightarrow 3O_{2} , the rate laws for the elementary reactions are Step 1 - O_{3}\rightarrow O_{2} + O Rate of consumption of O_{3} = k_{1}[O_{3}] (fast) Reverse: O_{2} + O\rightarrow O_{3} Rate of formation of O_{3} = K_{1}'[O_{2}][O] (fast) St...
Wed Mar 06, 2019 9:31 pm
Forum: Second Order Reactions
Topic: deciding which order
Replies: 2
Views: 133

### deciding which order

How do we determine whether we are dealing with a first, second, or zero order reaction? Any easy hints in questions or chemical equations?
Mon Mar 04, 2019 10:22 pm
Forum: General Rate Laws
Topic: Order Reaction/Rate Law
Replies: 3
Views: 139

### Order Reaction/Rate Law

Based on looking at a chemical reaction, what must be noticed to determine whether it be a First, Second, or Zeroth-Order reaction/rate law?
Sun Mar 03, 2019 11:53 pm
Forum: Interesting Applications: Rechargeable Batteries (Cell Phones, Notebooks, Cars), Fuel Cells (Space Shuttle), Photovoltaic Cells (Solar Panels), Electrolysis, Rust
Topic: electrolytic cell
Replies: 4
Views: 440

### electrolytic cell

In an electrolytic cell, the anode is labeled + (positive) and the anode is labeled - (negative) which is the opposite compared to the galvanic cell. Why is that so?
Sun Mar 03, 2019 10:51 pm
Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
Topic: Ecell and pH
Replies: 3
Views: 164

### Ecell and pH

An equation in the book to determine the pH of a solution is $Ecell=Ecell' + (0.0592) \cdot pH$. What is $Ecell'$ ? Is there a better way to do this?
Sun Mar 03, 2019 8:02 pm
Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
Topic: Cell Diagram
Replies: 4
Views: 160

### Cell Diagram

When writing the cell diagram, what is not included? Such as H2O(L) and H+?
Sun Mar 03, 2019 7:50 pm
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: Melting of ice
Replies: 9
Views: 390

### Melting of ice

Would the melting of ice on a hot summer day correlate with $\Delta G<0$ or $\Delta G>0$?
Sun Mar 03, 2019 7:43 pm
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: Gibbs free energy and temperature
Replies: 3
Views: 226

### Gibbs free energy and temperature

What's the relationship between Gibbs Free Energy and the temperature in the equation(s)?
Mon Feb 18, 2019 10:36 pm
Forum: Gibbs Free Energy Concepts and Calculations
Topic: K=e^lnK
Replies: 4
Views: 202

### K=e^lnK

Given $K=e^{lnK}$ , what exactly is $e$?
Mon Feb 18, 2019 5:02 pm
Forum: Gibbs Free Energy Concepts and Calculations
Topic: Finding standard reaction for a reaction
Replies: 3
Views: 149

### Finding standard reaction for a reaction

Given the reaction 2H_{2}O_{2}(l)\rightarrow 2H_{2}O(l)+O_{2}(g) , when trying to find standard reaction of entropy, enthalpy, and Gibbs Free Energy, why is O_{2} used in finding the standard reaction of entropy but not of enthalpy and Gibbs Free Energy? Is it just because it...
Mon Feb 18, 2019 2:55 pm
Forum: Gibbs Free Energy Concepts and Calculations
Topic: deltaG=0
Replies: 2
Views: 108

### deltaG=0

How does a reaction behave is deltaG=0?
Fri Feb 15, 2019 12:06 am
Forum: Concepts & Calculations Using Second Law of Thermodynamics
Topic: deltaS=qrev/T
Replies: 1
Views: 93

### deltaS=qrev/T

Is it possible to say that $\Delta S= \frac{-q_{irrev}}{T}$ since $\Delta S=\frac{q_{rev}}{T}$?
Thu Feb 14, 2019 9:27 pm
Forum: Thermodynamic Systems (Open, Closed, Isolated)
Topic: Liquid and moles
Replies: 8
Views: 532

### Liquid and moles

When given a chemical equation and say on the reactants side there is 2H2O(l), do the 2 moles of H2O become apart of the equilibrium constant and ICE table? Or does is it still insignificant due to H2O being a liquid?
Thu Feb 14, 2019 7:28 pm
Forum: Concepts & Calculations Using First Law of Thermodynamics
Topic: Temperature and Equilibrium
Replies: 3
Views: 138

### Temperature and Equilibrium

How can raising the temperature affect a reaction at equilibrium? More specifically, when given a reaction equation what will raising the temperature affect?
Thu Feb 14, 2019 7:05 pm
Forum: Calculating Work of Expansion
Topic: Work without change in volume
Replies: 8
Views: 520

### Work without change in volume

How can you find work at a constant temperature when there is no change in the volume?
Fri Feb 08, 2019 1:33 am
Forum: Concepts & Calculations Using First Law of Thermodynamics
Topic: Self Test 4B.3A
Replies: 1
Views: 168

### Self Test 4B.3A

Estimate the contribution of motion to the molar internal energy of water vapor at 25 degrees Celsius. The answer to this is 7.44 kJ.mol^-1. I see that they give the equation Um=3/2RT but it doesn't seem to be used here. Can someone explain this answer to the question? Thank you.
Wed Feb 06, 2019 10:56 pm
Forum: Thermodynamic Systems (Open, Closed, Isolated)
Topic: w=-PdeltaV
Replies: 6
Views: 215

### w=-PdeltaV

For both work equations of w=-nRTln(V2/V1) and w=-PdeltaV, what are all the conditions in which we would use one over the other?
Thu Jan 31, 2019 11:10 pm
Forum: Calculating Work of Expansion
Topic: Isolated System
Replies: 5
Views: 2552

### Isolated System

Since nothing exchanges with the surroundings in an isolated system, are there instances in which we still consider the heat of the surroundings?
Thu Jan 31, 2019 10:54 pm
Forum: Thermodynamic Systems (Open, Closed, Isolated)
Topic: q=-q
Replies: 4
Views: 183

### q=-q

When we know that q=-q in heat transfer, does this mean it has reached equilibrium?
Mon Jan 28, 2019 11:08 pm
Forum: Thermodynamic Systems (Open, Closed, Isolated)
Topic: Thermal Equilibrium
Replies: 5
Views: 151

### Thermal Equilibrium

When talking about thermal equilibrium, the book says that the equilibrium is dynamic in the sense that the molecular processes continue at equal rates. But what does it mean by "the molecular processes" still continuing? What exactly is still happening?
Mon Jan 21, 2019 8:38 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Ka3
Replies: 2
Views: 83

### Ka3

Will we need to deal with the Ka3 and pKa3 of a polyprotic?
Mon Jan 21, 2019 8:36 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Ka1 Ka2
Replies: 3
Views: 154

### Ka1 Ka2

Can Ka1 and Ka2 of a polyprotic be the same? If so, would you find the pH the same as any other solution?
Mon Jan 21, 2019 8:18 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Polyprotic
Replies: 2
Views: 112

### Polyprotic

How would you know that you are trying to find the pH of a polyprotic acid? Will we be told that the acid in the question is polyprotic?
Fri Jan 11, 2019 1:00 am
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Thermodynamics
Replies: 1
Views: 37

### Thermodynamics

In Topic 5i it says "K is large when $\Delta G^{\circ}_{r^}$ for a reaction is strongly negative." What is this $\Delta G^{\circ}_{r^}$?
Wed Jan 09, 2019 12:30 am
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Kinetics and Thermodynamics
Replies: 1
Views: 65

### Kinetics and Thermodynamics

How do you know when a question is pertaining to either kinetics or thermodynamics? Is the end result of one the same thing as the other, or even similar?
Tue Jan 08, 2019 9:44 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: K and Kc
Replies: 8
Views: 241

### K and Kc

Can someone explain to me the difference between K and Kc? When do you use one over the other? (I thought of this while looking at Topic 5H.3 or page 412 of the 7th edition book, just in case this helps)