What is the name of the molecule CH2O?
Seawater
Search found 49 matches
- Wed Mar 14, 2018 7:58 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 2762229
- Wed Mar 14, 2018 7:57 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 2762229
Re: Post All Chemistry Jokes Here
What do chemists call a benzene ring with iron atoms replacing the carbon atoms?
A ferrous wheel
A ferrous wheel
- Sat Mar 10, 2018 6:09 pm
- Forum: Zero Order Reactions
- Topic: graph of 0 order
- Replies: 10
- Views: 1937
Re: graph of 0 order
For differential rate law, you would graph rate vs. concentration, and since rate only depends on k and not concentration, it would be a horizontal line that drops straight down when the reactants are consumed. For integrated rate law, you graph concentration vs. time for zero order reactions, the y...
- Sat Mar 10, 2018 6:05 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 2762229
Re: Post All Chemistry Jokes Here
Why do white bears dissolve in water?
Because they're polar.
Because they're polar.
- Sat Mar 10, 2018 5:59 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 2762229
Re: Post All Chemistry Jokes Here
A small furry animal walks into a bar and orders a drink.
The bartender says, "Sorry, our maximum occupancy is 6.02 x 10^23. We can't a serve a mole."
The bartender says, "Sorry, our maximum occupancy is 6.02 x 10^23. We can't a serve a mole."
- Sat Mar 10, 2018 5:55 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 2762229
Re: Post All Chemistry Jokes Here
How many moles are in guacamole?
Avocado's number
Avocado's number
- Sat Mar 10, 2018 5:48 pm
- Forum: Second Order Reactions
- Topic: Differential vs Integrated
- Replies: 4
- Views: 868
Re: Differential vs Integrated
You would use differential rate law if you need to find the rate given certain concentrations.
Integrated rate law is used for finding concentrations given a certain time, or finding a final concentration from an initial concentration.
Integrated rate law is used for finding concentrations given a certain time, or finding a final concentration from an initial concentration.
- Sat Mar 10, 2018 5:39 pm
- Forum: First Order Reactions
- Topic: Log vs ln
- Replies: 9
- Views: 1182
Re: Log vs ln
There aren't really any cases log will be more convenient than ln, so just stick with natural log as it will always be more simple.
- Sat Mar 10, 2018 5:37 pm
- Forum: General Rate Laws
- Topic: Stoichiometric coefficients and order
- Replies: 5
- Views: 1105
Re: Stoichiometric coefficients and order
For the most part, you should not use the balanced reaction and stoichiometric coefficients to find the order of a reaction. The order of the reaction will most likely be given in a question, or you will be given experimental data or a graph which you can use as well.
- Tue Feb 27, 2018 3:00 pm
- Forum: Zero Order Reactions
- Topic: zero order slopes
- Replies: 5
- Views: 800
Re: zero order slopes
If you are graphing rate vs. time the slope will be zero, however if you are graphing [A] vs. time there will be a slope = -k
- Tue Feb 27, 2018 2:50 pm
- Forum: General Rate Laws
- Topic: Negative Sign [ENDORSED]
- Replies: 7
- Views: 900
Re: Negative Sign [ENDORSED]
We always want positive rates. Since [R] is decreasing it will be negative, and a negative sign will need to be added to counteract that.
- Mon Feb 26, 2018 10:37 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: Q and K
- Replies: 7
- Views: 829
Re: Q and K
Q and K are usually associated with equilibrium therefore the concepts regarding K>1 (products are favored) or Q>K (reactants are favored) or Q<K (products favored) are also constant
- Mon Feb 26, 2018 10:34 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: When do you need to include Pt? [ENDORSED]
- Replies: 5
- Views: 663
Re: When do you need to include Pt? [ENDORSED]
If there is no solid metal to act as a conductor, you use platinum
- Mon Feb 26, 2018 10:32 pm
- Forum: Balancing Redox Reactions
- Topic: Balancing number of electrons
- Replies: 10
- Views: 1042
Re: Balancing number of electrons
It would make most sense the multiply by the least common multiple so you won't have to do additional simplification at the end, however theoretically you could multiply by any multiple as long as the electrons cancel out
- Mon Feb 26, 2018 10:31 pm
- Forum: Balancing Redox Reactions
- Topic: Gibbs free energy of half reactions
- Replies: 4
- Views: 693
Re: Gibbs free energy of half reactions
Since Gibbs free energy is a state function it can be added
- Mon Feb 26, 2018 10:30 pm
- Forum: Balancing Redox Reactions
- Topic: Recognizing a redox reaction in acidic or basic solution
- Replies: 5
- Views: 603
Re: Recognizing a redox reaction in acidic or basic solution
Whether the reaction occurs in acidic or basic conditions will most likely be given
- Mon Feb 26, 2018 10:27 pm
- Forum: Balancing Redox Reactions
- Topic: Half Reaction Order
- Replies: 9
- Views: 2806
Re: Half Reaction Order
An oxidation reaction would have the electrons added on the right side of the arrow (electrons are lost) and a reduction reaction would have electrons on the left side (electrons are gained)
- Tue Feb 13, 2018 11:28 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Endothermic Favorable?
- Replies: 2
- Views: 1952
Re: Endothermic Favorable?
Look at the equation delta G = delta H - T(delta S) If a reaction is endothermic then delta H will be positive. It depends whether delta S is negative or positive, and whether T is a high or low value to determine whether delta G will be negative (which would mean the reaction is favorable). If Delt...
- Tue Feb 13, 2018 11:21 pm
- Forum: Concepts & Calculations Using Second Law of Thermodynamics
- Topic: Gibbs free energy
- Replies: 3
- Views: 450
Re: Gibbs free energy
delta Go is delta G at standard conditions and delta G without the o is just the change in Gibb's free energy under any conditions
- Tue Feb 13, 2018 8:58 pm
- Forum: Entropy Changes Due to Changes in Volume and Temperature
- Topic: Can deltaS = nR(ln(T2/T1)) be used to find change in entropy with varying temperature?
- Replies: 1
- Views: 430
Can deltaS = nR(ln(T2/T1)) be used to find change in entropy with varying temperature?
What equation should you use for when solving for the change in entropy with changing temperature? I thought the correct equation is deltaS = nC(ln(T2/T1)), however in the solutions manual the equation deltaS = nR(ln(T2/T1)) is used for question 9.13 Are these two equations interchangeable or should...
- Mon Feb 05, 2018 4:13 pm
- Forum: Calculating Standard Reaction Entropies (e.g. , Using Standard Molar Entropies)
- Topic: Favorability
- Replies: 4
- Views: 844
Re: Favorability
Anytime deltaG is negative the reaction will be spontaneous and therefore favorable. If deltaS is positive the reaction is also usually favorable, unless deltaH is greater than deltaS times T (which can occur at low temperatures).
- Mon Feb 05, 2018 4:09 pm
- Forum: Van't Hoff Equation
- Topic: Equation
- Replies: 4
- Views: 617
Re: Equation
He just wanted to make sure that we knew that the equation we most commonly use is not the actual Van't Hoff equation but a version of it more applicable to questions that we would be asked.
- Mon Feb 05, 2018 4:06 pm
- Forum: Concepts & Calculations Using Second Law of Thermodynamics
- Topic: The sign of the change in Gibb's Free Energy
- Replies: 6
- Views: 772
Re: The sign of the change in Gibb's Free Energy
When deltaG is negative it means the reaction is spontaneous, so it occurs easily and without work
- Mon Feb 05, 2018 3:56 pm
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: Closed vs. Isolated
- Replies: 8
- Views: 1044
Re: Closed vs. Isolated
A closed system can exchange energy but not matter, and an isolated system can exchange neither.
- Mon Jan 22, 2018 11:41 pm
- Forum: Phase Changes & Related Calculations
- Topic: Accounting for mass in phase changes
- Replies: 2
- Views: 411
Re: Accounting for mass in phase changes
It depends what units your constants are in. If the heat capacity given uses moles, then you would have to convert grams to moles so the units cancel. If given specific heat capacity using grams you would not need to convert grams to moles.
- Mon Jan 22, 2018 11:35 pm
- Forum: Phase Changes & Related Calculations
- Topic: Irreversible and Reversible
- Replies: 7
- Views: 681
Re: Irreversible and Reversible
It would be a good idea to know the difference between irreversible and reversible reactions, but if it shows up on the test it will only be a conceptual question.
- Mon Jan 22, 2018 11:33 pm
- Forum: Phase Changes & Related Calculations
- Topic: Question on Cv(vap)
- Replies: 2
- Views: 231
Re: Question on Cv(vap)
Cv(vap) is 2.01 (J/C*g) for H2O, it is not something you calculate but will be given, or you can look it up.
- Mon Jan 22, 2018 11:31 pm
- Forum: Phase Changes & Related Calculations
- Topic: Heat capacities
- Replies: 5
- Views: 580
Re: Heat capacities
In this case, J/g*C is the same as J/g*K
- Mon Jan 22, 2018 11:29 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: 8.45- why do you multiply?
- Replies: 5
- Views: 453
Re: 8.45- why do you multiply?
The delta H of 358.8 tells us the heat absorbed per mole of every substance in the reaction, this would mean there is 358.8 Kj/4 mol CS2, 358.8 KJ/4 mol C, and 358.8 KJ/ 1 mol S8. Therefore to find the heat absorbed by 1.25 mol of S8 we would multiply (358.8 KJ/ 1 mol S8) times (1.25 mol S8)
- Mon Jan 22, 2018 11:24 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Exothermic Reactions
- Replies: 2
- Views: 241
Re: Exothermic Reactions
Since the reactor will gain heat from the heat released by the reaction it will need to be cooled down
- Mon Jan 22, 2018 11:22 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Hesss Law
- Replies: 6
- Views: 527
Re: Hesss Law
yes, as it is in our lecture notes and in our homework
- Mon Jan 22, 2018 11:16 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Different Delta H. Question 8.57
- Replies: 2
- Views: 350
Re: Different Delta H. Question 8.57
The C stands for combustion, so delta H with subscript C means the enthalpy change of combustion
- Sun Dec 03, 2017 9:33 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Sigma and Pi bonds
- Replies: 2
- Views: 321
Re: Sigma and Pi bonds
Pi bonds are formed by leftover p orbitals, so for example if an atom of carbon was double bonded to another atom of carbon (with each carbon single-bonded to another atom), the sigma bond would be sp3 hybridized and the pi bond would be 2p hybridized.
- Sun Dec 03, 2017 9:29 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Monodentate vs Bidentate etc. [ENDORSED]
- Replies: 7
- Views: 5870
Re: Monodentate vs Bidentate etc. [ENDORSED]
Monodentate refers to a ligand that bonds to the central transition metal at one point. A bidentate is a ligand that can bond at two points to the transition metal. So basically you would look for how many atoms in the ligand are electron donors and could make bonds to the central TM.
- Sun Nov 26, 2017 7:37 pm
- Forum: Sigma & Pi Bonds
- Topic: drawing sigma/pi bonds
- Replies: 6
- Views: 878
Re: drawing sigma/pi bonds
All single bonds would be labeled as sigma bonds, double bonds would have one sigma bond and one pi bond, and triple bonds would have one sigma bond and two pi bonds.
- Sun Nov 26, 2017 7:25 pm
- Forum: SI Units, Unit Conversions
- Topic: Significant Figures in relation to molar mass [ENDORSED]
- Replies: 4
- Views: 11454
Re: Significant Figures in relation to molar mass [ENDORSED]
For molar mass try to use as many decimal places as possible to be the most accurate. The number of sig figs in your final answer will still be the same as the initial amount of sig figs in the mass given (or whatever value given that has the least amount of sig figs)
- Sun Nov 19, 2017 11:39 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Chelates
- Replies: 3
- Views: 389
Re: Chelates
A chelate is a complex containing a ligand that forms a ring of atoms that includes the central metal ion. Chelating ligands can bind cations tightly, so they can be used to remove metals from solutions.
- Sun Nov 19, 2017 11:36 pm
- Forum: Biological Examples
- Topic: Cobalt
- Replies: 4
- Views: 562
Re: Cobalt
It's biological significance is that it is found in vitamin B12.
- Sun Nov 12, 2017 10:52 pm
- Forum: Lewis Structures
- Topic: Radicals
- Replies: 7
- Views: 769
Re: Radicals
Sophia Bozone 3 3B wrote:Veronica Rasmusen 1E wrote:Most often, yes. With an odd number of electrons, there will be one electron ending up without a pair.
Thank you of this illuminating knowledge benevolent sir :-*
Why welcome fair kind maiden, hath 14a been treating thee kindly?
- Sun Nov 12, 2017 10:49 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Formal charge and lewis structures
- Replies: 5
- Views: 582
Re: Formal charge and lewis structures
It depends on what the question is asking, if the questions wants the most stable structure or the one with the least formal charge then yes you will have to calculate the formal charges on each atom and find the most correct structure. For more basic molecules this will often by the first one you d...
- Sun Nov 12, 2017 10:35 pm
- Forum: Lewis Structures
- Topic: Radicals
- Replies: 7
- Views: 769
Re: Radicals
Most often, yes. With an odd number of electrons, there will be one electron ending up without a pair.
- Sun Nov 12, 2017 10:30 pm
- Forum: Formal Charge and Oxidation Numbers
- Topic: Lewis Structures and Formal Charge
- Replies: 7
- Views: 1363
Re: Lewis Structures and Formal Charge
There are many cases where you will draw the most stable lewis structure right off the bat, but it's always a good idea to check formal charge in case just so you don't end up losing points.
- Sun Nov 12, 2017 10:26 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Drawing lewis structures
- Replies: 5
- Views: 635
Re: Drawing lewis structures
In most cases the best lewis structure will be the one with a central atom of the lowest ionization energy and formal charges of zero on each atom.
- Sun Nov 05, 2017 9:13 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 2762229
Re: Post All Chemistry Jokes Here
Two scientists walk into a bar The first one says “I’ll have some H2O.” The second one says, “I’ll have some H2O too.” Then he dies.
- Sun Nov 05, 2017 9:12 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 2762229
Re: Post All Chemistry Jokes Here
Did you hear about the guy who's temperature got down to absolute zero?
Don't worry, he's 0k.
Don't worry, he's 0k.
- Sun Oct 29, 2017 10:38 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 2762229
Re: Post All Chemistry Jokes Here
I don't trust atoms... they make up everything
- Sun Oct 29, 2017 10:38 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 2762229
Re: Post All Chemistry Jokes Here
I try to tell chemistry jokes,
but there is no reaction :(
but there is no reaction :(
- Sun Oct 15, 2017 6:31 pm
- Forum: Properties of Light
- Topic: Homework 1.3
- Replies: 2
- Views: 250
Homework 1.3
Can someone explain why the extent of the change in the electrical field at a given point decreases when the frequency of electromagnetic radiation decreases?
- Sat Oct 14, 2017 5:46 pm
- Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
- Topic: Confused about hw question 1.15 [ENDORSED]
- Replies: 1
- Views: 343
Confused about hw question 1.15 [ENDORSED]
Question: In the ultraviolet spectrum of atomic hydrogen, a line is observed at 102.6 nm. Determine the values of n for the initial and final energy levels of the electron during the emission of energy that leads to this spectral line. I was able to find the frequency (v) using the wavelength but I'...