Search found 22 matches
- Sat Mar 17, 2018 10:30 pm
- Forum: General Rate Laws
- Topic: 15.35
- Replies: 1
- Views: 450
Re: 15.35
It's because the [A]=1/60[A0] meaning that 1/[A] would be 1/1/60[A0] which becomes 16/[A0]
- Sat Mar 17, 2018 10:28 pm
- Forum: Reaction Mechanisms, Reaction Profiles
- Topic: Catalyst and Intermediate
- Replies: 7
- Views: 1024
Catalyst and Intermediate
How do you know the difference between a catalyst and in intermediate in a reaction mechanism??
- Sat Mar 17, 2018 10:26 pm
- Forum: *Alkanes
- Topic: The symbol R
- Replies: 5
- Views: 1509
Re: The symbol R
Sometimes it can also include halogen, nitrogen or oxygen.
- Sat Mar 17, 2018 7:29 pm
- Forum: Reaction Mechanisms, Reaction Profiles
- Topic: Elementary Reaction
- Replies: 2
- Views: 442
Elementary Reaction
How do you know when an elementary reaction is slow or fast?
- Mon Feb 19, 2018 5:46 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Example 14.4
- Replies: 1
- Views: 203
Example 14.4
For the reaction of Pt(s)|H2(g)|HCl(aq)|Hg2Cl2(s)|Hg(l), it becomes Hg2Cl(s) + H2(g) --> 2Hg(l) + 2Cl-(aq) + 2H+(aq).
What does the Pt stand for and why isn't it included in the reaction equation?
What does the Pt stand for and why isn't it included in the reaction equation?
- Tue Feb 13, 2018 9:06 pm
- Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
- Topic: Heat and Enthalpy
- Replies: 1
- Views: 326
Heat and Enthalpy
What exactly is the difference between heat and enthalpy??
- Tue Feb 13, 2018 1:22 am
- 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: 9.25 Question
- Replies: 1
- Views: 292
9.25 Question
How can there be 6 orientations for the molecule SO2F02?
- Fri Feb 09, 2018 12:19 am
- Forum: Entropy Changes Due to Changes in Volume and Temperature
- Topic: Pressure and Volume
- Replies: 3
- Views: 435
Re: Pressure and Volume
Because the units cancel out in the ratio, the unit doesn't really matter. You just have to make sure that the units of the two volume or pressure are the same.
- Thu Feb 08, 2018 3:19 pm
- Forum: Van't Hoff Equation
- Topic: Exothermic and decrease in tempterature
- Replies: 4
- Views: 672
Re: Exothermic and decrease in tempterature
Whenever a temperature is lowered, the exothermic process is favored so yes, the formation of the product will be favored. I would say that the favorability of the product or reactant when the temperature changes depend on what type of a reaction it is (endothermic or exothermic).
- Thu Feb 08, 2018 3:16 pm
- Forum: Concepts & Calculations Using Second Law of Thermodynamics
- Topic: Clausius inequality
- Replies: 1
- Views: 267
Clausius inequality
I was reading the textbook and I wasn't too sure on the concept of Clausius inequality. How exactly does deltaS >q/T work if the equation that are given to us are deltaS=q/T?
- Thu Feb 01, 2018 5:11 pm
- Forum: Entropy Changes Due to Changes in Volume and Temperature
- Topic: Change of Entropy for V and T
- Replies: 2
- Views: 338
Change of Entropy for V and T
Why does the equation of entropy change for change in volume use V2/V1 while it is P1/P2 for the change in pressure?
- Thu Feb 01, 2018 5:09 pm
- Forum: Concepts & Calculations Using Second Law of Thermodynamics
- Topic: units conversion for entropy
- Replies: 6
- Views: 1025
Re: units conversion for entropy
It doesn't really matter but usually entropy is in J/K due to the equation of S=q/T
- Mon Jan 29, 2018 5:37 pm
- Forum: Calculating Work of Expansion
- Topic: Reversible vs Irreversible
- Replies: 4
- Views: 528
Reversible vs Irreversible
I read the textbook and I still don't really understand the concept of reversible and irreversible expansion. What exactly are the difference between the two in terms of the work??
- Thu Jan 25, 2018 3:55 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Bond Enthalpies
- Replies: 5
- Views: 614
Re: Bond Enthalpies
This is because bond enthalpies uses the average bond, and doesn't take the intermolecular forces into account.
- Thu Jan 25, 2018 3:54 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Calculating heat (q)
- Replies: 4
- Views: 2122
Re: Calculating heat (q)
This will depend on the c value that you have. If you have the molar heat capacity and the second equation will be used and if you have the specific heat capacity the first one will be used.
- Thu Jan 25, 2018 3:49 pm
- Forum: Phase Changes & Related Calculations
- Topic: enthalpy of fusion/vaporization
- Replies: 3
- Views: 427
Re: enthalpy of fusion/vaporization
You basically take the negative of the enthalpy of fusion/vaporization if the process is in reverse.
- Thu Jan 18, 2018 9:55 pm
- Forum: Calculating Work of Expansion
- Topic: Work for compression/expansion
- Replies: 2
- Views: 290
Work for compression/expansion
Can someone explain why the value for work is positive when it is compression and why it is negative when it is expansion??
- Thu Jan 18, 2018 9:49 pm
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: Is there a way specific way to approach into seeing if open closed or isolated?
- Replies: 9
- Views: 830
Re: Is there a way specific way to approach into seeing if open closed or isolated?
Open system has transfer of heat and material; closed system has transfer of heat but not the transfer of material; isolated system has no transfer of heat or material.
- Thu Jan 18, 2018 9:47 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Molar heat capacity
- Replies: 3
- Views: 343
Molar heat capacity
I'm still confused about the molar heat capacity. How can the specific heat capacity for gas change depending on the value of volume or pressure?
- Wed Jan 10, 2018 4:34 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Bond Enthalpies
- Replies: 5
- Views: 469
Bond Enthalpies
In lecture today, we learned how to use bond enthalpy to calculate ΔH. Just to clarify, does it mean that ΔH= ∑bond broke - ∑bond formed?
- Wed Jan 10, 2018 4:28 pm
- Forum: Phase Changes & Related Calculations
- Topic: Heat and Phase Transition
- Replies: 3
- Views: 384
Re: Heat and Phase Transition
So basically, the temperature wouldn't change because that heat is required to change the phase. The temperature would stay constant until the phase transitions and then it would start changing its temperature if more heat is given/lost.
- Wed Jan 10, 2018 4:22 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Exothermic reaction in bond enthalpy example in lecture
- Replies: 5
- Views: 370
Re: Exothermic reaction in bond enthalpy example in lecture
Whenever the enthalpy is negative it is an exothermic reaction as it means that it RELEASES that amount of energy rather than absorbing it.