Search found 22 matches

by Phu Mai 1G
Wed Mar 09, 2016 8:37 am
Forum: *Alkanes and Substituted Alkanes (Staggered, Eclipsed, Gauche, Anti, Newman Projections)
Topic: Numbering order for substituents
Replies: 1
Views: 317

Re: Numbering order for substituents

No, in this case, it would depend on which ever comes first ethyl or flouro, whichever comes first has the lowest number. If they are tied for lowest number then ethyl would get the lowest number because alphabetically ethyl comes first. Ethyl does not take priority over flouro in naming and only co...
by Phu Mai 1G
Sat Feb 27, 2016 2:38 pm
Forum: *Cycloalkenes
Topic: Nomenclature
Replies: 3
Views: 389

Nomenclature

Why is this not 1-Ethyl-2,2-dimethylcyclopropane? Doesn't the ethyl group comes first alphabetically? I looked at the course reader and it does not have a similar problem. My guess would be because the 1,1 - 2 is lower than 1 - 2,2 Can someone confirm?
by Phu Mai 1G
Sat Feb 27, 2016 2:06 pm
Forum: *Alkanes
Topic: Double headed vs single headed arrow
Replies: 1
Views: 274

Re: Double headed vs single headed arrow

Single head arrows means only one electron is transferred while double head means 2 electrons are transferred.
by Phu Mai 1G
Sun Feb 21, 2016 9:58 pm
Forum: *Nucleophiles
Topic: -CH3 Nucleophile
Replies: 2
Views: 557

Re: -CH3 Nucleophile

-CH3 is where it is attached. because CH3 has an extra electron, it can forms bonds and break and give electrons. See ClCH3 in the course reader on page 85.
by Phu Mai 1G
Mon Feb 15, 2016 9:41 am
Forum: Reaction Mechanisms, Reaction Profiles
Topic: Determining the slow reaction mechanism
Replies: 1
Views: 273

Re: Determining the slow reaction mechanism

Generally, the slow step will be given to us as are the examples in the book.
by Phu Mai 1G
Sun Feb 07, 2016 5:42 pm
Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
Topic: Value for n
Replies: 1
Views: 386

Re: Value for n

You need to balance the number of electrons in a reaction, the number of electrons that are transferred is the "n" value which you use.
by Phu Mai 1G
Sun Jan 31, 2016 11:24 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Cathode vs Anode
Replies: 1
Views: 264

Re: Cathode vs Anode

You will be given a standard reduction potential chart and match the elements from the half-reaction.

Standard Reduction Table Ex: http://chemwiki.ucdavis.edu/Analytical_Chemistry/Electrochemistry/Redox_Chemistry/Standard_Reduction_Potential
by Phu Mai 1G
Sun Jan 24, 2016 1:00 pm
Forum: Calculating Work of Expansion
Topic: Irreversible vs Reversible --> work equations
Replies: 5
Views: 6633

Re: Irreversible vs Reversible --> work equations

In irreversible reaction, the pressure is immediately changed, (not slowly in contrast to reversible), as a result, a lot of work is loss because of friction. On the test or homework, I think they will tell you whether the reaction is in a reversible or irreversible so you don't have to worry about ...
by Phu Mai 1G
Sat Jan 09, 2016 8:03 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: Homework Problem 8.47
Replies: 1
Views: 702

Homework Problem 8.47

For a certain reaction at a constant pressure, delta H= -15 kJ and 22 kJ of expansion work is done on the system. What is delta U or internal energy for this process? I did this problem and thought work by expansion was negative. Because the volume is expanding or a positive delta V, work would be n...
by Phu Mai 1G
Thu Dec 03, 2015 11:24 pm
Forum: *Making Buffers & Calculating Buffer pH (Henderson-Hasselbalch Equation)
Topic: Problem 13.39
Replies: 1
Views: 281

Problem 13.39

See attachment for problem On part b, can you use Henderson-Hasselbalch Equation to figure out the POH then PH, because we know the initial value of base and its conjugate acid ? I did it and it seem to work, better question, can you use this method on the test rather than drawing out ICE tables acc...
by Phu Mai 1G
Tue Dec 01, 2015 3:25 pm
Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
Topic: How to identify weak/strong acids/bases
Replies: 1
Views: 361

Re: How to identify weak/strong acids/bases

To remember strong acids, I remember most of the halogen group (HI, HBr, HCl) except for HF because water cannot easily get between those two bond as easily thus not as soluble. Then you have to manually memorize HNO3, H2SO4, HClO4. For strong base, remember all the elements from group 1 (LiOH, NaOH...
by Phu Mai 1G
Sun Nov 29, 2015 7:51 pm
Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
Topic: Rounding off
Replies: 2
Views: 362

Re: Rounding off

If you look back at the equilibrium unit, page 123 in the course reader, you can see that K is small if K<10-3 then the acid or base will not likely to break apart or produce as much ions. 10-5 as you mentioned would be considered a small K.
by Phu Mai 1G
Fri Nov 27, 2015 9:59 am
Forum: Acidity & Basicity Constants and The Conjugate Seesaw
Topic: Conjugate bases/acids
Replies: 1
Views: 371

Re: Conjugate bases/acids

For your acid and conjugate base question, I found this http://chemwiki.ucdavis.edu/Physical_Chemistry/Acids_and_Bases/Acid%2F%2FBase_Reactions/Conjugate_Acids-base_Pairs"onclick="window.open(this.href);return false; to be very helpful with illustrations to help with my understandings To remember st...
by Phu Mai 1G
Mon Nov 23, 2015 2:32 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Square Planar Shape
Replies: 2
Views: 462

Re: Square Planar Shape

Because transition metals tend to not have lone pair electrons, your answer will be tetrahedral, assuming the ligands are monodentate since it is impossible to create square planar without two lone pair electrons.
by Phu Mai 1G
Sun Nov 22, 2015 2:04 pm
Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
Topic: PH of a Weak Acid
Replies: 1
Views: 328

PH of a Weak Acid

To clarify on what Dr. Lavelle said on Friday, let's suppose the concentration of the [H 3 0 + ] is ...*10^-8 (any thing smaller than 10^-7) in the final solution. The solution would remain neutral because of the original amount of H 3 0 + formed by water. So my question is can you ever have PH of 8...
by Phu Mai 1G
Wed Nov 11, 2015 5:17 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Solving for the correct equilibrium relation HW 11.43
Replies: 1
Views: 264

Re: Solving for the correct equilibrium relation HW 11.43

1. Set up equilibrium constant and ICE box
k=((PN2)(PO2))/(PNO)2
NO N2 O2
I 1 0 0
C -2x +x +x
E (1-2x) x x

Ans: k=(x2)/(1.0-2x)2
by Phu Mai 1G
Wed Oct 28, 2015 4:30 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Why Can't T-shaped Molecules be Trigonal Planar?
Replies: 3
Views: 1221

Why Can't T-shaped Molecules be Trigonal Planar?

In a T-Shaped molecule like ICl3, why can't we make the top and bottom paired electrons with chlorine bond shaped like a trigonal planar? (similar to square planar as it also have 2 set of paired electrons top and bottom).
by Phu Mai 1G
Fri Oct 09, 2015 4:22 pm
Forum: Properties of Light
Topic: Intensity of Light
Replies: 2
Views: 471

Re: Intensity of Light

Hi Laurel, I found the definition of intensity (http://cse.ssl.berkeley.edu/segwayed/le"onclick="window.open(this.href);return false; ... sure3.html) as the rate of which energy is delivered to a surface area. The number of photons per surface area affects the intensity. Imagine 10 photons per cm^2 ...
by Phu Mai 1G
Fri Oct 02, 2015 4:46 pm
Forum: Limiting Reactant Calculations
Topic: 2 Questions from M. Limiting Reactants
Replies: 5
Views: 2669

Re: 2 Questions from M. Limiting Reactants

Round 2 Here I come, This one I thought was pretty cool... Another ratio one, though it took me quite long to figure this out. First I calculated the actual mass percentage of the sample for carbon. (120/144=.833 or 83.3%) and hydrogen (8/144=.055 or 5.5%) Then find the percent of oxygen by 100-(83....
by Phu Mai 1G
Fri Oct 02, 2015 4:15 pm
Forum: Limiting Reactant Calculations
Topic: 2 Questions from M. Limiting Reactants
Replies: 5
Views: 2669

Re: 2 Questions from M. Limiting Reactants

*Disclaimer: I could be wrong so feel free to correct me as I am typing this locked out of my dorm so I could not check my solution manual, but here is how I did it: 1. Because this is a combustion reaction, the amount of oxygen is in excess thus, one cannot truly calculate the amount of oxygen in s...
by Phu Mai 1G
Fri Oct 02, 2015 1:11 pm
Forum: Properties of Light
Topic: HW 1.9
Replies: 1
Views: 342

Re: HW 1.9

To check which wavelength corresponds with which event, you can check in the beginning of the chapter 1. Specifically page 4, table 1.1, the table should give you an estimate of where the wavelengths are.

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