Search found 42 matches
- Wed Mar 13, 2019 11:35 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 2760062
Re: Post All Chemistry Jokes Here
If Avogadro calls, tell him to leave his number.
- Wed Mar 13, 2019 11:35 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 2760062
Re: Post All Chemistry Jokes Here
All the best chemistry jokes...Argon
- Wed Mar 13, 2019 11:34 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 2760062
Re: Post All Chemistry Jokes Here
In a sports relay race, a chemical kinetics specialist runs slowly, and his group loses the race.
When the chemical kinetics specialist is asked why he ran slowly, his reply was “I always wanted to be the significant rate determining step”.
When the chemical kinetics specialist is asked why he ran slowly, his reply was “I always wanted to be the significant rate determining step”.
- Wed Mar 06, 2019 9:22 pm
- Forum: Second Order Reactions
- Topic: multiple choice rate
- Replies: 1
- Views: 320
multiple choice rate
For a reaction 2A + B 2C, with the rate equation: Rate = k[A]2[B] (a) the order with respect to A is 1 and the order overall is 1. (b) the order with respect to A is 2 and the order overall is 2. (c) the order with respect to A is 2 and the order overall is 3. (d) the order with respect to B is 2 an...
- Wed Mar 06, 2019 9:21 pm
- Forum: Second Order Reactions
- Topic: multiple choice kinetics
- Replies: 1
- Views: 298
multiple choice kinetics
The speed of a chemical reaction (a) is constant no matter what the temperature is. (b) is independent of the amount of contact surface of a solid involved. (c) between gases should in all cases be extremely rapid because the average kinetic energy of the molecules is great. (d) between ions in aque...
- Wed Mar 06, 2019 8:32 pm
- Forum: Second Order Reactions
- Topic: unique rate
- Replies: 1
- Views: 207
unique rate
What is a unique rate of a problem in kinetics? for example 6th edition textbook number 15.3 (c) - the answer key doesn't have a section for this...
- Wed Feb 27, 2019 9:49 am
- Forum: Balancing Redox Reactions
- Topic: salt bridge vs porous disk
- Replies: 4
- Views: 2094
salt bridge vs porous disk
What happens if there is no salt bridge in a galvanic cell? also what is the difference between a salt bridge and a porous disk? How does that affect the lines you draw
- Wed Feb 27, 2019 9:47 am
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: draw galvanic cell
- Replies: 3
- Views: 425
draw galvanic cell
For the upcoming exam this week will we be expected to know how to draw out a Galvanic cell?
- Wed Feb 27, 2019 9:45 am
- Forum: Administrative Questions and Class Announcements
- Topic: DOWNLOAD SESSION WORKSHEETS HERE - Sun 7-9PM (Karen)
- Replies: 179
- Views: 21845
Re: DOWNLOAD SESSION WORKSHEETS HERE - Sun 7-9PM (Karen)
Did Karen post her most recent handout answer key that we weren't able to go over in session?
- Wed Feb 27, 2019 9:44 am
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: E^o(cell) vs. Ecell
- Replies: 6
- Views: 12942
Re: E^o(cell) vs. Ecell
^o means it is at standard conditions, this also can be applied to G or S
- Thu Feb 21, 2019 9:54 am
- Forum: Balancing Redox Reactions
- Topic: k from lnK
- Replies: 5
- Views: 3797
k from lnK
how do you find the K value from lnK. For example in problem 11.19 a and b from 6th edition? I never learned this and the solutions manual skips the process...
- Wed Feb 20, 2019 7:40 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: anode reversal
- Replies: 1
- Views: 214
anode reversal
what is the difference between an anode before and after reversal? ex: 6th addition problem 14.11
- Wed Feb 20, 2019 7:39 pm
- Forum: Balancing Redox Reactions
- Topic: H+ vs H3O+
- Replies: 10
- Views: 927
Re: H+ vs H3O+
It should not matter because they mean the same thing, but the textbook prefers H+
- Wed Feb 20, 2019 12:09 pm
- Forum: Ideal Gases
- Topic: overall grade points
- Replies: 2
- Views: 338
overall grade points
How many overall points minimum do you need to get a B- or a B in this class. The syllabus only states that 250/500 is a C-.
- Mon Feb 11, 2019 9:43 am
- Forum: Concepts & Calculations Using Second Law of Thermodynamics
- Topic: ideal gases and reactions
- Replies: 1
- Views: 210
ideal gases and reactions
How do ideal gases affect a reaction? I know that it may change the C value such as 5/2R or 3/2R
- Mon Feb 11, 2019 9:42 am
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: cooling a system
- Replies: 3
- Views: 359
cooling a system
If you cool a system how does it affect the reaction?
- Mon Feb 11, 2019 9:41 am
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Homework during midterm week [ENDORSED]
- Replies: 5
- Views: 425
Homework during midterm week [ENDORSED]
What is the homework for this week? Is there a specific topic we should do problems for? (We aren't learning any new concepts this week)
- Tue Feb 05, 2019 10:13 pm
- Forum: Administrative Questions and Class Announcements
- Topic: negative and positive entropy
- Replies: 3
- Views: 579
negative and positive entropy
What represents a negative change in entropy and a positive one? based on the type of reaction
- Tue Feb 05, 2019 10:07 pm
- Forum: Phase Changes & Related Calculations
- Topic: isothermal vs reversible
- Replies: 1
- Views: 202
isothermal vs reversible
if something is isothermal should you always assume that it is also reversible? what is the difference between the two
- Tue Feb 05, 2019 9:57 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: thermo equation explanation
- Replies: 4
- Views: 486
thermo equation explanation
What are you calculating with this equation: delt S (entropy) = q/T and why does T need to be in K?
- Wed Jan 30, 2019 10:42 pm
- Forum: Ideal Gases
- Topic: derivatives and integrals
- Replies: 6
- Views: 954
derivatives and integrals
Can someone explain what Lavelle was going over in lecture today about how dV or the derivative in V solves for something? And also I don't understand why the main equation we went over today involves taking an antiderivative/integral. Is this because we want to solve for the derivative and find the...
- Wed Jan 30, 2019 10:40 pm
- Forum: Ideal Gases
- Topic: pH and pOH
- Replies: 18
- Views: 1784
Re: pH and pOH
Typically if you are given a base, you solve for pOH, but if you are asked to find the pH, then you must convert from pOH to pH by using this formula: -14.00 = pOH + pH. Or 14.00 - pOH = pH
- Wed Jan 30, 2019 10:38 pm
- Forum: Ideal Gases
- Topic: breaking bond - heat released and gained
- Replies: 5
- Views: 847
breaking bond - heat released and gained
I have a question related to both Biology and Chemistry. When I was at a PLF today for lifesci 7A, they said that when you break a bond, you go from high potential E to low potential E, which means that it is exergonic, because you release energy. However, I was told last quarter in chemistry that i...
- Sun Jan 27, 2019 6:16 pm
- Forum: Administrative Questions and Class Announcements
- Topic: thermo equations
- Replies: 1
- Views: 233
thermo equations
What are the main equations used for Thermodynamics that we should get comfortable with and what do they solve for?
- Tue Jan 22, 2019 9:54 pm
- Forum: Administrative Questions and Class Announcements
- Topic: DOWNLOAD SESSION WORKSHEETS HERE - Sun 7-9PM (Karen)
- Replies: 179
- Views: 21845
Re: DOWNLOAD SESSION WORKSHEETS HERE - Sun 7-9PM (Karen)
for problem 4 on the second worksheet, how do you find the concentration of CO3 2- you are given the concentration of H2CO3
- Tue Jan 22, 2019 9:12 pm
- Forum: Administrative Questions and Class Announcements
- Topic: DOWNLOAD SESSION WORKSHEETS HERE - Sun 7-9PM (Karen)
- Replies: 179
- Views: 21845
Re: DOWNLOAD SESSION WORKSHEETS HERE - Sun 7-9PM (Karen)
can you please explain the steps of this question on worksheet 2: How many grams of formic acid, HCOOH, do you need to prepare 1.00L of a pH 3.26
solution? Ka of formic acid = 1.8 x 10-4? I have no idea how to solve
solution? Ka of formic acid = 1.8 x 10-4? I have no idea how to solve
- Mon Jan 21, 2019 8:49 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: help with homework 12.57
- Replies: 2
- Views: 192
help with homework 12.57
can someone explain step by step how you solve 12.57 6th edition. I think the solutions manual is incorrect or is just confusing...
- Mon Jan 21, 2019 8:46 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: solving for pka and ka and ph
- Replies: 2
- Views: 163
solving for pka and ka and ph
what does 10-ph equal?
- Mon Jan 21, 2019 7:59 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: how to determine if something is an acid or base
- Replies: 4
- Views: 350
how to determine if something is an acid or base
How can you easily identify is something is going to work as an acid or a base in an aqueous solution. For example, in hw 12.55 6th edition, CH3COOH serves as an acid, but it has an OH group, so I would think it would work as a base....Will it be more clear to identify on the test?
- Mon Jan 21, 2019 7:40 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Pka and ka
- Replies: 1
- Views: 197
Pka and ka
does lower pka mean that it's a stronger acid? and does high ka go with strong acid as well?
- Thu Jan 17, 2019 9:22 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: writing equations
- Replies: 1
- Views: 133
writing equations
If you were to be given a base - such as Bf3(OH)- and you knew that you needed to make an equation to solve. How would you set it up? What is the rule of thumb and how to you know when to add water?
- Tue Jan 15, 2019 9:24 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: help with equilibrium equations
- Replies: 1
- Views: 177
help with equilibrium equations
How do you know how to rewrite the equation in homework problem 12.37. For example, it asks for weak acids to write the equilibrium equation and Ka value and if its a weak base to write the equation and Kb. It also asks about conj base. So for part (a) it asks this for HClO2 and I wrote the expressi...
- Mon Jan 14, 2019 6:32 pm
- Forum: General Science Questions
- Topic: conceptual question about brackets
- Replies: 1
- Views: 282
conceptual question about brackets
what does it mean when you put a zero around a base...for example: (Ba(OH)2)0. It shows this on the answer key for 12.25
- Mon Jan 14, 2019 6:24 pm
- Forum: General Science Questions
- Topic: molarity question
- Replies: 2
- Views: 299
molarity question
For the 6th edition textbook homework 12.23 part (a), how do you know that since the Kw provided is 2.1x10^-14 that that is equivalent to x^2. So the problem can be set up as (H3O+)(OH-)=x^2. Is this because if you take the square root of 2.1x10^-14 is 1.4x10^-7 mol/L? I wouldn't have thought of thi...
- Thu Jan 10, 2019 9:26 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: lavelle's email
- Replies: 1
- Views: 192
lavelle's email
what is Lavelle's email address? I couldn't find it on the website
- Tue Jan 08, 2019 6:56 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: hw questions - points
- Replies: 9
- Views: 652
Re: hw questions - points
I understand that homework points are separate. But can you ask questions on chemistry community about homework and have that count toward your 3 points?
- Tue Jan 08, 2019 6:48 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: hw questions - points
- Replies: 9
- Views: 652
hw questions - points
Do homework questions count towards our weekly 3 discussion points?
- Tue Jan 08, 2019 6:46 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: liquid vs aqueous
- Replies: 2
- Views: 8459
liquid vs aqueous
what is the difference between a liquid and an aqueous solution?
- Tue Jan 08, 2019 6:45 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: aqueous solutions
- Replies: 2
- Views: 298
aqueous solutions
If a chemical equation has aqueous solutions in it that means that it can dissolve in water. So if you were to write an equation, how do you know whether or not to include water?
- Mon Jan 07, 2019 6:08 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: 6th edition hw problem 11.31
- Replies: 2
- Views: 152
6th edition hw problem 11.31
for part c, how do you know if there is a tendency to form more reactants or more products...how does the Q value being less than K value affect his?
- Mon Jan 07, 2019 6:02 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: 6th edition hw problem 11.7
- Replies: 3
- Views: 216
Re: 6th edition hw problem 11.7
Thank you! How do you find the % decomposition? it says (6/11) x 100% but where does 6 come from?
- Mon Jan 07, 2019 5:31 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: 6th edition hw problem 11.7
- Replies: 3
- Views: 216
6th edition hw problem 11.7
I don't understand how you can identify which flask represents the point in time at which the reaction has reached equilibrium? Can someone please explain this. I tried counting out the number of X2 molecules as well as the dissociation of diatomic molecules... The answer is flask #3 but I don't kno...