n = total # of e- transferred in the redox reaction.
Fe2+ goes to Fe ----- 2 e- are transferred, but there are 2 moles, so 2X2= 4.
n= 4
Search found 31 matches
- Sun Mar 19, 2017 12:29 pm
- Forum: Balancing Redox Reactions
- Topic: Winter 2013 Final Q4
- Replies: 3
- Views: 796
- Sun Mar 19, 2017 12:29 pm
- Forum: Balancing Redox Reactions
- Topic: Winter 2013 Final Q4
- Replies: 3
- Views: 796
Re: Winter 2013 Final Q4
n = total # of e- transferred in the redox reaction.
Fe2+ goes to Fe ----- 2 e- are transferred, but there are 2 moles, so 2X2= 4.
n= 4
Fe2+ goes to Fe ----- 2 e- are transferred, but there are 2 moles, so 2X2= 4.
n= 4
- Sun Mar 19, 2017 12:08 pm
- Forum: *Alkanes and Substituted Alkanes (Staggered, Eclipsed, Gauche, Anti, Newman Projections)
- Topic: Newman Projection
- Replies: 2
- Views: 1556
Re: Newman Projection
All the Newman Projections we have done thus far have been a between TWO carbon atoms. The other carbon atoms are considered if they are bonded to the carbon atoms we are examining. They are drawn on the outside of the circle, whereas the carbon atoms being specifically analyzed are in the center of...
- Sun Mar 19, 2017 12:05 pm
- Forum: *Constitutional and Geometric Isomers (cis, Z and trans, E)
- Topic: Z and E how to tell the difference
- Replies: 2
- Views: 1580
Re: Z and E how to tell the difference
Ensure that you are focussing on the "priority rules," in regards to breaking apart double bonds and giving precedence to elements with higher atomic #. Also looking at the line structure and where H atoms are bonded helps establish the geometry and provides a visual representation of wher...
- Fri Mar 17, 2017 7:01 pm
- Forum: *Alcohols
- Topic: Numbering alcohols
- Replies: 2
- Views: 1230
Re: Numbering alcohols
This thought process works if the described alcohol is an alkane (only single bods present). If the molecule is an alkene (double bond) then, the before the suffix of the alcohol, you must indicate where the double bond is located. This is because an alcohol isn't a terminal atom, numbers are vital ...
- Thu Mar 16, 2017 10:11 am
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 4017050
Re: Post All Chemistry Jokes Here
Some simple, yet enjoyable jokes:
Every dipole has its moments.
It takes alkynes to make a world!
Every dipole has its moments.
It takes alkynes to make a world!
- Thu Mar 09, 2017 4:59 pm
- Forum: *Cycloalkenes
- Topic: Order of naming
- Replies: 6
- Views: 1950
Re: Order of naming
According to IUPAC, double bonds and triple bonds take precedence in the order of which the structure is named (this is an exception where alphabetical order doesn't appear).
- Sun Mar 05, 2017 10:10 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 4017050
Re: Post All Chemistry Jokes Here
Making bad chemistry jokes because all the good ones Argon...
- Sun Mar 05, 2017 10:05 pm
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: adsorption?
- Replies: 2
- Views: 688
Re: adsorption?
The rate of adsorption is governed by the rate of arrival of molecules at the surface and the proportion of incident molecules which undergo adsorption. The rate of adsorption (per unit area of surface) as a product of the incident molecular flux, F , and the sticking probability , S . R(ads) = S . ...
- Tue Feb 21, 2017 9:33 pm
- Forum: Kinetics vs. Thermodynamics Controlling a Reaction
- Topic: Activation Energy
- Replies: 4
- Views: 1000
Re: Activation Energy
The larger this ratio, the smaller the rate (hence the negative sign.) This means that high temperature and low activation energy favor larger rate constants, and thus speed up the reaction. And because these terms occur in an exponent, their effects on the rate are quite substantial. Therefore, tem...
- Tue Feb 21, 2017 9:28 pm
- Forum: Reaction Mechanisms, Reaction Profiles
- Topic: Units of rate constant k
- Replies: 2
- Views: 591
Re: Units of rate constant k
Zero order: mol/s
First Order: s^-1
Second Order: L * mol^-1 * s^-1
Third Order: L^2 * mol ^-2 * s^-1
First Order: s^-1
Second Order: L * mol^-1 * s^-1
Third Order: L^2 * mol ^-2 * s^-1
- Sat Feb 11, 2017 4:28 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 4017050
Re: Post All Chemistry Jokes Here
SHORT BUT SWEET...
How about the chemical workers… are they unionized?
How about the chemical workers… are they unionized?
- Tue Jan 31, 2017 4:46 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Quiz 1 Preparation Answers
- Replies: 130
- Views: 25887
Re: Quiz 1 Preparation Answers (#11)
How many grams of water can be heated from 25.0 degrees Celsius to 100 degrees Celsius by the heat released from converting 49.7g of PbO to Pb? The converting reaction is: PbO(s) + C(s) --> Pb(s) + CO(g) deltaH = -106.9kJ How do I go about setting up this problem in order to solve it? q = (n)ΔH (49...
- Thu Jan 26, 2017 9:41 am
- Forum: Entropy Changes Due to Changes in Volume and Temperature
- Topic: Entropy and Stability
- Replies: 1
- Views: 468
Re: Entropy and Stability
When discussing the relationship between entropy in regards to the stability of a system, when a maximum heat source is reached, the point can be considered "stable." The state of maximum thermodynamic stability is reached when entropy is maximized and enthalpy is maximized.
- Sat Jan 21, 2017 2:51 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 4017050
Re: Post All Chemistry Jokes Here
Q: What do you get when you mix sulfur, tungsten, and silver?
A: SWAG
A: SWAG
- Thu Jan 19, 2017 9:56 am
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Calorimeters [ENDORSED]
- Replies: 3
- Views: 795
Re: Calorimeters [ENDORSED]
A coffee cup calorimeter occurs at constant pressure because it is exposed to the atmosphere, because it is partially unsealed. Therefore, volume is allowed to fluctuate. In contrast, a bomb calorimeter, occurs at constant volume and pressure is allowed to fluctuate because it is completely sealed f...
- Thu Jan 12, 2017 2:35 pm
- Forum: Phase Changes & Related Calculations
- Topic: Irreversible Process
- Replies: 1
- Views: 496
Re: Irreversible Process
An irreversible process occurs due to the finite gradient between the two states of a particular system. In the irreversible process the initial state of the system and surroundings cannot be restored from the final state and increases decisively and it cannot be reduced back to its initial value. A...
- Sun Dec 04, 2016 1:15 pm
- Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
- Topic: Pi bond vs. sigma bond question [ENDORSED]
- Replies: 2
- Views: 690
Re: Pi bond vs. sigma bond question [ENDORSED]
It helps to think of a sigma bond as a single bond and a pi bond as a double bond.
- Sun Dec 04, 2016 1:09 pm
- Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
- Topic: bond order question [ENDORSED]
- Replies: 3
- Views: 907
Re: bond order question [ENDORSED]
The bond order is 2.5 and not enough for triple bond. Thus the molecule will have a double bond and is a table molecule.
* Bond order is a special relationship for Bond length (thus strength)
* Bond order is a special relationship for Bond length (thus strength)
- Mon Nov 28, 2016 5:40 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: the unit "bar"
- Replies: 1
- Views: 522
Re: the unit "bar"
The bar is the metric unit of pressure. 1 bar = 100,000 Pascal. 1 atm = 1.01325 bar.
- Thu Nov 24, 2016 11:54 am
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: What does it mean for an equilibrium to favor products or reactants?
- Replies: 1
- Views: 23164
Re: What does it mean for an equilibrium to favor products or reactants?
When Kc>1 you can also say that kforward>kreverse and inversely if Kc<1 then k reverse>k forward. To favor either the reactants or the products in equilibrium is to say the formation of either the reactants or products is favored, as indicated by the rate constants. If a reaction is not at equilibri...
- Mon Nov 14, 2016 9:09 pm
- Forum: Naming
- Topic: Determining Oxidation [ENDORSED]
- Replies: 2
- Views: 698
Re: Determining Oxidation [ENDORSED]
Okay so... (en)2 = 0 charge. (CN) = -1 charge (Cl) = -1 charge (Cl) = -1 Charge. By addition, you get: -1 + -1 + -1 = -3. The compound as a whole is not an ion (not a cation or anion)so it has a neutral charge of 0. In this case to make this compound 0, the metal has to have an oxidation number of 3...
- Mon Nov 14, 2016 9:03 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Naming coordination compounds
- Replies: 1
- Views: 589
Re: Naming coordination compounds
The sodium atom on the outside of the parenthesis accounts for a charge of 1+. The ammine is 0 and the Chlorine is -3 ( -1 x 3 atoms). And because the compound is not an ion, you know the total number of oxidation numbers must equal zero (neutral). So... 1 + 0 -3 + x = 0. SOLVE FOR X (oxidation numb...
- Thu Nov 10, 2016 11:46 am
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 4017050
Re: Post All Chemistry Jokes Here
Here's a very witty, yet simple humorous joke for your afternoon.
- Tue Nov 01, 2016 8:27 pm
- Forum: Bond Lengths & Energies
- Topic: Bond length, 2012 Midterm Question 6B
- Replies: 3
- Views: 994
Re: Bond length, 2012 Midterm Question 6B
Follow these steps. 1) Find lewis structures for all ions. 2) Ensure you draw structures correctly. 3) Examine the type of bonds being formed (i.e. single, double, triple, etc). Note: The more bonds that appear between two atoms/ions, the more energy is present, and the closer the pull of electrons ...
- Tue Nov 01, 2016 8:22 pm
- Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
- Topic: What is MO theory for? [ENDORSED]
- Replies: 20
- Views: 9001
Re: What is MO theory for? [ENDORSED]
To add on...Molecular orbital theory allows us to understand the probability of finding the electrons at particular points around the molecule. MO Theory also allows us to understand bond order which is significant for the understanding of reactivities. Prior to learning about MO, we learned about t...
- Mon Oct 24, 2016 5:40 pm
- Forum: Electronegativity
- Topic: CO2 vs. CS2 ionic character
- Replies: 3
- Views: 3928
Re: CO2 vs. CS2 ionic character
When analyzing the ionic character of a compound its important to realize the electronegativity difference between the elements in the compound. For example, C has an electronegativity is 0.8. Where C (2.6 EN) - O (3.4 EN) = 0.8 EN. The same thing goes for CS2 = C (2.6 EN) - (2.6) = 0. The greater t...
- Mon Oct 17, 2016 1:05 pm
- Forum: Resonance Structures
- Topic: Electrons in Resonance [ENDORSED]
- Replies: 4
- Views: 947
Re: Electrons in Resonance [ENDORSED]
In regards to resonance structures, what factors determine which atoms/ions exhibit the greatest resonance stabilization?
- Tue Oct 11, 2016 3:44 pm
- Forum: Einstein Equation
- Topic: Wavelengths [ENDORSED]
- Replies: 3
- Views: 1001
Re: Wavelengths [ENDORSED]
When solving problems for wavelength, yes its important to understand what the question's units contain, it's important to understand the SI unit system. When using the speed of light formula, and Broglie formula the standard SI unit is m. Thus, you must convert your wavelength (if given in nm) to m...
- Tue Oct 04, 2016 2:11 pm
- Forum: Student Social/Study Group
- Topic: Chemistry Joke
- Replies: 18
- Views: 3390
Re: Chemistry Joke
To all those chemists that have been agitated by atoms...
Don't trust atoms, they make up everything.
- Your Fellow Chemistry Student,
Diana Visco
Don't trust atoms, they make up everything.
- Your Fellow Chemistry Student,
Diana Visco
- Tue Sep 27, 2016 1:53 pm
- Forum: Balancing Chemical Reactions
- Topic: How familiar should we be with Naming compounds? [ENDORSED]
- Replies: 8
- Views: 2810
Re: How familiar should we be with Naming compounds? [ENDORSED]
HI, in response to your question...To better understand the periodic table and trends, it is extremely helpful to know the name of common compounds and polyatomic ions. A few resources that have helped me over the few years when I have taken chemistry, include resources like Kahn Academy, Fernbank.e...