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Re: Quiz 3 Winter 2017

Posted: Tue Mar 07, 2017 12:56 am
by BrianaBarr2A
304751905 wrote:for #1, why do we need "iso" infant of propyl? wouldn't the 4- signify the branching?


This is because "iso" identifies that there is 2 CH3's coming off of 1 CH (in all there is 3 carbons so prop). That is what CH(CH3)2 means so iso is used and it is connected to the 4th carbon and there are 10 carbons with single bonds so the the name is 4-isopropyl-decane

Re: Quiz 3 Winter 2017

Posted: Tue Mar 07, 2017 1:02 am
by BrianaBarr2A
Julie Barreto 3A wrote:how would you draw out 2-butene or anything with a number in front of it ???


For 2-butene the number identifies where the double bond is located since butene (the -ene means a double bond) so it is located on the second Carbon. For anything else with a number in front of it, it just means what carbon it is located on and the number is associated with whatever is directly after it in the name.

Re: Quiz 3 Winter 2017

Posted: Tue Mar 07, 2017 1:18 am
by ariana_cruz_1C
Jocelyn_Dao_2N wrote:Why is the answer for number 4, 4-butyl-1,2-dimethylcyclohexane and not 1,butyl-3,4-butylcyclohexane?

remember we want to start numbering wherever we could get the lowest number, so in 4-butyl-1,2-dimethylcyclohexane (4+2+1 gives us 7) whereas 1,butyl-3,4-butylcyclohexane (4+3+1 gives us 8)

Re: Quiz 3 Winter 2017

Posted: Tue Mar 07, 2017 2:41 am
by Annie Zhang_ 3C
304751905 wrote:for #1, why do we need "iso" infant of propyl? wouldn't the 4- signify the branching?



I believe the iso- indicates a structural connectivity of (CH3)2CH- , as indicated in page 9 of the Ochem green booklet.

Re: Quiz 3 Winter 2017

Posted: Tue Mar 07, 2017 9:47 am
by Minu Reddy
Can someone please help me to understand when to use iso-, neo-, sec-, and tert, when doing IUPAC naming?

Thank you

Re: Quiz 3 Winter 2017

Posted: Tue Mar 07, 2017 10:31 am
by Ariana de Souza 4C
304751905 wrote:for #1, why do we need "iso" infant of propyl? wouldn't the 4- signify the branching?


No, because the 4 signifies from what carbon on the MAIN BRANCH you're substituent is on. WIthin the substituent itself, though, there is branching, and that's why you'd either say iso-propyl (common name) or maybe 1-methyl-ethyl (IUPAC)

Re: Quiz 3 Winter 2017

Posted: Tue Mar 07, 2017 10:46 am
by SydneyKusumoputro_3K
Could someone help me understand the thought process behind #7?

Re: Quiz 3 Winter 2017

Posted: Tue Mar 07, 2017 11:35 am
by Molika Soben_3J
Jocelyn_Dao_2N wrote:Why is the answer for number 4, 4-butyl-1,2-dimethylcyclohexane and not 1,butyl-3,4-butylcyclohexane?


When naming, once you get a lower number, then that's it. Since 2 is smaller than 3, then the name of the compound should be the one that includes the 2, not the 3.

Re: Quiz 3 Winter 2017

Posted: Tue Mar 07, 2017 1:17 pm
by Mizuno_Mikaela_1D
Julie Barreto 3A wrote:how would you draw out 2-butene or anything with a number in front of it ???


The 2 means the carbon carbon double bond starts at carbon 2 (between the second and third carbon) so it would be CH3-CH=CH-CH3.

Re: Quiz 3 Winter 2017

Posted: Tue Mar 07, 2017 3:17 pm
by Vandan_Patel_3L
Julie Barreto 3A wrote:how would you draw out 2-butene or anything with a number in front of it ???


The 2 in two butene means that there is a double bond as it ends in "en" and the double bond is between Carbon 2 and 3.

Re: Quiz 3 Winter 2017

Posted: Tue Mar 07, 2017 3:45 pm
by Vandan_Patel_3L
Can someone explain when to use tert vs neo and sec vs iso please?

Re: Quiz 3 Winter 2017

Posted: Tue Mar 07, 2017 4:08 pm
by AlexandraOsterland_3E
For the quiz will we have to know how to draw transition states? Or will just drawing the arrows for each step in the reaction suffice?

Re: Quiz 3 Winter 2017

Posted: Tue Mar 07, 2017 5:55 pm
by Yinhan_Liu_1D
#2, it asks us to draw a structure, when we are drawing the line structure, do we specify (draw out) the carbon where the parent chain is branched? Or we just draw a branch?

Re: Quiz 3 Winter 2017

Posted: Tue Mar 07, 2017 6:26 pm
by Ethan_Kato_1D
For number 5, how are there 2 intermediates?

Re: Quiz 3 Winter 2017

Posted: Tue Mar 07, 2017 6:46 pm
by TiengTum2D
Julie Barreto 3A wrote:how would you draw out 2-butene or anything with a number in front of it ???


Remember that 'ene ' just means that it has double bonds and the number indicates on which carbon the double bond is being located. What u can do first is to write out all carbons, place the double where needed and fill it out with hydrogens. Hope this helps!

Re: Quiz 3 Winter 2017

Posted: Tue Mar 07, 2017 7:49 pm
by Natalie Hunt 1E
AlexandraOsterland_3E wrote:For the quiz will we have to know how to draw transition states? Or will just drawing the arrows for each step in the reaction suffice?


I believe we will need to know how to draw transition states. I was at a UA session today, and we went over transition states and how to draw them.

Re: Quiz 3 Winter 2017

Posted: Tue Mar 07, 2017 8:36 pm
by Corey Switzler 2L
Where can we find the answers to practice quiz 3?

Re: Quiz 3 Winter 2017

Posted: Tue Mar 07, 2017 8:37 pm
by Corey Switzler 2L
Also, since we're only covering alkanes and cycloalkanes on quiz 3, does that mean some of the types questions of practice quiz 3 won't be on the real quiz?

Re: Quiz 3 Winter 2017

Posted: Tue Mar 07, 2017 9:00 pm
by Natalie Hunt 1E
Corey Switzler 2L wrote:Where can we find the answers to practice quiz 3?


The answers to the quiz are posted at the beginning of this thread.

Re: Quiz 3 Winter 2017

Posted: Tue Mar 07, 2017 9:15 pm
by Armani Dodson 1A
On one of the examples in the course reader the naming says "tert" do you know why that is?

Re: Quiz 3 Winter 2017

Posted: Tue Mar 07, 2017 9:58 pm
by 604746385
Tert refers to tertiary carbon meaning it is connected to 3 other carbons

Re: Quiz 3 Winter 2017

Posted: Tue Mar 07, 2017 10:04 pm
by Madison_Moore_1I
Is quiz 3 going to be more focused on naming organic compounds rather than kinetics?

Re: Quiz 3 Winter 2017

Posted: Tue Mar 07, 2017 10:07 pm
by MariaReina_Garcia_3E
Julie Barreto 3A wrote:how would you draw out 2-butene or anything with a number in front of it ???


The -ene refers to a double carbon bond, while the 2 refers to the carbon in which the double bond begins. Therefore 2-butene will be c-c=c-c

Re: Quiz 3 Winter 2017

Posted: Tue Mar 07, 2017 10:13 pm
by Korosh Bahrami
Does anyone know how to do #11 on the Quiz 2 Preparation in the Course Reader?

Re: Quiz 3 Winter 2017

Posted: Tue Mar 07, 2017 11:03 pm
by Chem_Mod
Madison_Moore_1I wrote:Is quiz 3 going to be more focused on naming organic compounds rather than kinetics?


See earlier post in this thread and please read what I posted on Saturday:
"Your Quiz 3 covers more Kinetics."

Re: Quiz 3 Winter 2017

Posted: Tue Mar 07, 2017 11:04 pm
by Rachelle_Stark_3H
Where do I find the answers to the quiz 3 preparatory quiz??

Re: Quiz 3 Winter 2017

Posted: Tue Mar 07, 2017 11:10 pm
by Natalie Hunt 1E
Rachelle_Stark_3H wrote:Where do I find the answers to the quiz 3 preparatory quiz??


Dr. Lavelle posted the quiz 3 answers towards the beginning of this thread.

Re: Quiz 3 Winter 2017

Posted: Tue Mar 07, 2017 11:55 pm
by Logan 3C
Julie Barreto 3A wrote:how would you draw out 2-butene or anything with a number in front of it ???


The 2 in 2-butene signifies that the location of the double bond is after the second carbon. So you would draw this as a normal butene, just with the double bond after the 2nd carbon. In other cases, you would draw either the substituents or the double/triple bonds based on the carbon number given.

Re: Quiz 3 Winter 2017

Posted: Wed Mar 08, 2017 12:44 am
by Morgan Zapasnik 1N
For question number 2, can someone explain how ethyl & methyl are on the 3rd carbon? And what does it mean by the third carbon in the hexane line structure? A description or picture would be greatly appreciated!

Re: Quiz 3 Winter 2017

Posted: Wed Mar 08, 2017 2:08 am
by sophianguyen_1N
304751905 wrote:for #1, why do we need "iso" in front of propyl? wouldn't the 4- signify the branching?

No, the 4 only denotes which carbon the substituent is attached to. If we did not use iso, the naming of the substituent would be completely different.

Re: Quiz 3 Winter 2017

Posted: Wed Mar 08, 2017 2:12 am
by stephanieyang_3F
304751905 wrote:for #1, why do we need "iso" in front of propyl? wouldn't the 4- signify the branching?


4 signifies that there's a substituent on the 4th carbon of the chain and the reason you put isopropyl instead of propyl is because it's not a straight alkyl substituent CH2CH2CH3, but rather CH(CH3)2. How you can distinguish the two is that for CH(CH3)2 there's a parentheses which signifies that they are both substituents of CH.

Re: Quiz 3 Winter 2017

Posted: Wed Mar 08, 2017 3:21 am
by K Phelan 3D
Julie Barreto 3A wrote:how would you draw out 2-butene or anything with a number in front of it ???


We have not yet learned how to draw alkenes, which 2-butene is as seen by its infix. This won't be needed for quiz three. (The two shows where the double bond is)

Re: Quiz 3 Winter 2017

Posted: Wed Mar 08, 2017 5:29 am
by Preet_Bains_1D
304751905 wrote:for #1, why do we need "iso" in front of propyl? wouldn't the 4- signify the branching?

The "iso" signifies that it is CH(CH3)2 instead of CH2CH2CH3. If the substituent was CH2CH2CH3 then the answer would be 4-propyldecane.

Re: Quiz 3 Winter 2017

Posted: Wed Mar 08, 2017 5:32 am
by Preet_Bains_1D
Ethan_Kato_1D wrote:For number 5, how are there 2 intermediates?

Look in the course reader on page 84 and 85. It has an example of the same mechanism.

Re: Quiz 3 Winter 2017

Posted: Wed Mar 08, 2017 8:10 am
by Chem_Mod
Vandan_Patel_3L wrote:Can someone explain when to use tert vs neo and sec vs iso please?


A good summary can be found here: http://web.chem.ucla.edu/~harding/IGOC/ ... _name.html
And in your organic textbook.

TLDR: Tert- where the functional group is bound is at a carbon bonded to 3 other carbons.
Neo- All except for 2 carbons are in a continuous chain, where those 2 extra carbons form a terminal tert-butyl group.
Sec- Mostly relevant for 4 chain carbons. Functional group is bound to a secondary carbon (a carbon that is attached to 2 other carbons)
Iso- All except for 1 carbon is part of the main chain.

Re: Quiz 3 Winter 2017

Posted: Wed Mar 08, 2017 8:16 am
by Chem_Mod
Morgan Zapasnik 1N wrote:For question number 2, can someone explain how ethyl & methyl are on the 3rd carbon? And what does it mean by the third carbon in the hexane line structure? A description or picture would be greatly appreciated!


Image

Re: Quiz 3 Winter 2017

Posted: Wed Mar 08, 2017 9:35 am
by Rika Jitosho 2E
304751905 wrote:for #1, why do we need "iso" in front of propyl? wouldn't the 4- signify the branching?

If you draw out the structure, you'll see the branching of (CH3)2CH, which is how you know to include the prefix iso-. By that same logic, if the branching had (CH3)3C, you would use the prefix neo- but only with five or more carbons. See lecture notes and Introduction to Organic Chemistry.

Re: Quiz 3 Winter 2017

Posted: Wed Mar 08, 2017 10:41 am
by andrea mejia
For number 5, how do we know the first step is the slow one?
Also, could someone explain when and how to use iso- in naming? Or just how to do #1?

Re: Quiz 3 Winter 2017

Posted: Wed Mar 08, 2017 10:42 am
by Imani Johnson 1H
For iuPac naming, when dealing with a cycloalkane, how do you determine which molecule to number as #1, say the cycloalkane has two substituents...for example, a cyclohexane with substiuents of CH3 and Br?

Re: Quiz 3 Winter 2017

Posted: Wed Mar 08, 2017 11:23 am
by Chem_Mod
Imani Johnson 1H wrote:For iuPac naming, when dealing with a cycloalkane, how do you determine which molecule to number as #1, say the cycloalkane has two substituents...for example, a cyclohexane with substiuents of CH3 and Br?



If your substituents are not functional groups, then you would number it whichever way gives you the lowest set of numbers. If one of your substituents is a functional group, then that will take priority in numbering. In the example you mentioned, bromo- comes before methyl- so the bromine would get the smaller number.

Re: Quiz 3 Winter 2017

Posted: Wed Mar 08, 2017 11:24 am
by 104469125
On page 83: electrophilic addition of Hbr to 2-Butene
Could we have the positions of Br and H switched for the final answer?

Re: Quiz 3 Winter 2017

Posted: Wed Mar 08, 2017 11:31 am
by Chem_Mod
Zhanna Khnkoyan 2E wrote:On page 83: electrophilic addition of Hbr to 2-Butene
Could we have the positions of Br and H switched for the final answer?


Yes. We will not give you examples in which the final placement of Br and H will matter. As you take more organic chemistry, you will learn that there are rules which govern which carbon bonds to the Br and which bonds to the H.

Re: Quiz 3 Winter 2017

Posted: Wed Mar 08, 2017 11:33 am
by 104469125
andrea mejia wrote:For number 5, how do we know the first step is the slow one?
Also, could someone explain when and how to use iso- in naming? Or just how to do #1?


I was also wondering the same thing. How do we know that the first step is the rate limiting step? Does it have to do with the intermediates in step 1?

Re: Quiz 3 Winter 2017

Posted: Wed Mar 08, 2017 12:33 pm
by Caity Colt 2N
andrea mejia wrote:For number 5, how do we know the first step is the slow one?
Also, could someone explain when and how to use iso- in naming? Or just how to do #1?

For 5, the first step is the slow one because it involves breaking two bonds (Carbon-carbon double bond and the H-Br bond). Step two only involves the bond forming between carbon and Br.

For 1, the parent chain would be decane, since there are 5 carbons. The substituent, CH(CH3)2 would be named isopropyl because iso is used to describe the structural pattern (CH3)2CH-- and there are four carbons (meaning it is propyl). Since (counting from right to left) the substituent is on the fourth carbon.

Re: Quiz 3 Winter 2017

Posted: Wed Mar 08, 2017 1:53 pm
by Emma Cole 3F
How do you know when to add "iso" when naming compounds?

Re: Quiz 3 Winter 2017

Posted: Wed Mar 08, 2017 2:21 pm
by Audrey_Hall_2I
Does anyone know good kinetics problems to do in preparation for the quiz? Thanks!

Re: Quiz 3 Winter 2017

Posted: Wed Mar 08, 2017 4:40 pm
by RitaChang_2C
Zhanna Khnkoyan 2E wrote:
andrea mejia wrote:For number 5, how do we know the first step is the slow one?
Also, could someone explain when and how to use iso- in naming? Or just how to do #1?


I was also wondering the same thing. How do we know that the first step is the rate limiting step? Does it have to do with the intermediates in step 1?


Step one is the rate limiting step as it is slower. In the first step you need to break two bonds and form one, whereas in step two you only need to form one bond.

Re: Quiz 3 Winter 2017

Posted: Wed Mar 08, 2017 5:30 pm
by Ashley Curtis 2O
BrianaBarr2A wrote:
304751905 wrote:for #1, why do we need "iso" infant of propyl? wouldn't the 4- signify the branching?


This is because "iso" identifies that there is 2 CH3's coming off of 1 CH (in all there is 3 carbons so prop). That is what CH(CH3)2 means so iso is used and it is connected to the 4th carbon and there are 10 carbons with single bonds so the the name is 4-isopropyl-decane


How is this different from regular propyl?

Re: Quiz 3 Winter 2017

Posted: Wed Mar 08, 2017 9:45 pm
by KarinaOropeza_2L
Blake_Katsev_2E wrote:Shouldnt number 4 be 5-butyl instead of 4-butyl?


You have to go in the direction that gives you the lowest numbers. So in this case you would go counterclockwise.

Re: Quiz 3 Winter 2017

Posted: Wed Mar 08, 2017 9:56 pm
by Rachel_Harland_3I
304751905 wrote:for #1, why do we need "iso" in front of propyl? wouldn't the 4- signify the branching?

Its isopropyl because its CH(CH3)2 and not CH3(CH2)2 which would be propyl. as a rule of thumb, the two CH3 indicates iso

Re: Quiz 3 Winter 2017

Posted: Wed Mar 08, 2017 10:03 pm
by KarinaOropeza_2L
Blake_Katsev_2E wrote:Shouldnt number 4 be 5-butyl instead of 4-butyl?


You have to go in the direction that gives you the lowest numbers. So in this case you would go counterclockwise.

Re: Quiz 3 Winter 2017

Posted: Wed Mar 08, 2017 10:34 pm
by Banik_Housepian_2K
Teddy_Rosenbluth wrote:Would vinyls be considered functional groups and therefor we don't need to know it for Quiz 3?

I had this question as well, but im pretty sure it wont be on the quiz.

Re: Quiz 3 Winter 2017

Posted: Wed Mar 08, 2017 10:52 pm
by Maya Kandah 3M
Audrey_Hall_2I wrote:Does anyone know good kinetics problems to do in preparation for the quiz? Thanks!


I would recommend the book problems from chapter 15

Re: Quiz 3 Winter 2017

Posted: Thu Mar 09, 2017 1:25 am
by Chris_Rudewicz_3H
We still get to drop our lowest quiz score, right?

Re: Quiz 3 Winter 2017

Posted: Thu Mar 09, 2017 1:36 am
by Chris_Rudewicz_3H
So if we have say, for example, a 35/40 on quiz 1, a 37/40 on quiz 2, and then we get a 10/40 on quiz 3, what will happen is we will get a 37/40 on quiz 3 in the gradebook?

Re: Quiz 3 Winter 2017

Posted: Thu Mar 09, 2017 7:09 am
by Nikhita_Jaaswal_2H
304751905 wrote:for #1, why do we need "iso" in front of propyl? wouldn't the 4- signify the branching?

You have to place "iso" in front for the propyl because 4 signifies where the propyl is connected to the decane, not the branching on the propyl substituent itself.

Re: Quiz 3 Winter 2017

Posted: Thu Mar 09, 2017 9:12 am
by Chem_Mod
Chris_Rudewicz_3H wrote:So if we have say, for example, a 35/40 on quiz 1, a 37/40 on quiz 2, and then we get a 10/40 on quiz 3, what will happen is we will get a 37/40 on quiz 3 in the gradebook?


Yes

Re: Quiz 3 Winter 2017

Posted: Thu Mar 09, 2017 9:40 am
by Jocelyn Sandoval 3B
For the quiz 3 preparation, why does electrophilic addition have 2 intermediates? Graphically, isn't there only 1?

Re: Quiz 3 Winter 2017

Posted: Thu Mar 09, 2017 11:18 am
by BetcyGaspar_3C
Jocelyn Sandoval 3B wrote:For the quiz 3 preparation, why does electrophilic addition have 2 intermediates? Graphically, isn't there only 1?
Pages 84-85 of the course reader demonstrate the graph of the problem in quiz 3 preparation. Just because there is only one dip in the graph does not mean it stands for one intermediate.

Re: Quiz 3 Winter 2017

Posted: Thu Mar 09, 2017 7:16 pm
by EmilyLeibovitch2E
Is it correct that electrophilic addition always has 2 intermediates where SN2 only has 1?

Re: Quiz 3 Winter 2017

Posted: Thu Mar 09, 2017 10:09 pm
by Leila_Shamir_3J
For number 5 in the practice quiz, is the reaction an electrophilic addition reaction because the hydrogen is being added to the bromide molecule?

Re: Quiz 3 Winter 2017

Posted: Thu Mar 09, 2017 10:19 pm
by Leila_Shamir_3J
On number 7 on the practice quiz, why does the butene become butane after the addition of Cl2?

Re: Quiz 3 Winter 2017

Posted: Thu Mar 09, 2017 10:36 pm
by Natalie Rotstein 3J
The quiz 3 prep includes alkenes and cycloalkenes, and Lavelle's responses to questions on the quiz prep problems seem to imply that we are expected to know how to solve all of the problems in the quiz prep, but the beginning of the thread it says alkanes and cycloalkanes in the textbook and only up to pg 96 (prior to the start of alkenes) in the course reader - do we need to know how to solve problems involving alkenes or not?

Re: Quiz 3 Winter 2017

Posted: Thu Mar 09, 2017 10:44 pm
by Chem_Mod
EmilyLeibovitch2E wrote:Is it correct that electrophilic addition always has 2 intermediates where SN2 only has 1?


SN2 does not have any intermediates. Perhaps you meant transition states.

Electrophilic addition has 2 transition states and SN2 has 1. Correct.

Ask me after class if this is not clear.

Re: Quiz 3 Winter 2017

Posted: Thu Mar 09, 2017 10:45 pm
by Chem_Mod
Leila_Shamir_3J wrote:On number 7 on the practice quiz, why does the butene become butane after the addition of Cl2?


Because it no longer has a double bond.

Re: Quiz 3 Winter 2017

Posted: Thu Mar 09, 2017 11:00 pm
by Chem_Mod
Natalie Rotstein 3J wrote:The quiz 3 prep includes alkenes and cycloalkenes, and Lavelle's responses to questions on the quiz prep problems seem to imply that we are expected to know how to solve all of the problems in the quiz prep, but the beginning of the thread it says alkanes and cycloalkanes in the textbook and only up to pg 96 (prior to the start of alkenes) in the course reader - do we need to know how to solve problems involving alkenes or not?


"Lavelle's responses to questions on the quiz prep problems seem to imply that we are expected to know how to solve all of the problems in the quiz prep"

I explicitly stated in the quiz 3 prep answers above:
"Q3. Alkenes not covered in your Quiz 3."


Q3 was an alkene structure and we covered these structures and names (geometric isomers, cis/trans, E/Z) this week (which is not on quiz 3).

Your question is also ambiguous. Do you mean alkene structures, cis/trans, etc. The answer is again no, not for quiz 3.

If you mean electrophilic addition across a double bond which I covered three times for an entire lecture last week. Yes. A double bond is an alkene. One cannot cover the electrophilic addition (across a double bond) reaction mechanism and not have an alkene in the reaction.

Re: Quiz 3 Winter 2017

Posted: Thu Mar 09, 2017 11:36 pm
by Natalie Rotstein 3J
Thank you for clarifying, I was mainly confused about whether we would need to know alkene structures/formulas from the name for alkenes other than the ones mentioned in lecture in the context of the electrophilic addition, such as ethene and 2-butene, but I think I understand what we need to know now. Essentially, we need to know how alkenes function in an electrophilic addition reaction, and whether they are electrophilic or nucleophilic, as well as some specific alkene-involving-reactions discussed in lecture, but for the most part, we don't need to know the IUPAC naming of alkenes or the structure based on their names?
Thanks!
Chem_Mod wrote:I explicitly stated in the quiz 3 prep answers above:
"Q3. Alkenes not covered in your Quiz 3."


Q3 was an alkene structure and we covered these structures and names (geometric isomers, cis/trans, E/Z) this week (which is not on quiz 3).

Your question is also ambiguous. Do you mean alkene structures, cis/trans, etc. The answer is again no, not for quiz 3.

If you mean electrophilic addition across a double bond which I covered three times for an entire lecture last week. Yes. A double bond is an alkene. One cannot cover the electrophilic addition (across a double bond) reaction mechanism and not have an alkene in the reaction.

Re: Quiz 3 Winter 2017

Posted: Fri Mar 10, 2017 12:56 am
by nicoleclarke_lec1M
Julie Barreto 3A wrote:how would you draw out 2-butene or anything with a number in front of it ???

This is an alkene and it would be a 4-carbon molecule with a double bond between the 2nd and 3rd carbon.

Re: Quiz 3 Winter 2017

Posted: Fri Mar 10, 2017 3:47 am
by Milan Hirpara 3K
What are the units for A in the Arrhenius equation?

Re: Quiz 3 Winter 2017

Posted: Fri Mar 10, 2017 9:25 am
by Chem_Mod
Milan Hirpara 3K wrote:What are the units for A in the Arrhenius equation?


Great question.

In the Arrhenius Equation A has the same units as k (the rate constant).

This makes sense since one can obtain A from the y-intercept in the ln k vs 1/T plot where the y-intercept is ln A.


Note that the units of k are dependent on the order of the reaction.

Re: Quiz 3 Winter 2017

Posted: Fri Mar 10, 2017 10:25 am
by 404639305
emilie liu 3G wrote:Will we have to know tert and sec for the quiz or can we use the IUPAC names for them instead of common names?


Lavelle said that he would never explicitly ask for common names, he said he with either just ask for the name (in which case you have the option of IUPAC or common) or just eh IUPAC.

Re: Quiz 3 Winter 2017

Posted: Fri Mar 10, 2017 10:54 am
by 404639305
Jocelyn_Dao_2N wrote:Why is the answer for number 4, 4-butyl-1,2-dimethylcyclohexane and not 1,butyl-3,4-butylcyclohexane?


remember you name in alphabetical order

Re: Quiz 3 Winter 2017

Posted: Sun Mar 12, 2017 7:58 pm
by Arie Hakimi 1L
will the answers to the quiz be posted?

Re: Quiz 3 Winter 2017

Posted: Sun Mar 12, 2017 9:22 pm
by Chem_Mod
Arie Hakimi 1L wrote:will the answers to the quiz be posted?


I posted the answers to Quiz 3 Preparation on March 4th. See answers above.

Re: Quiz 3 Winter 2017

Posted: Mon Mar 13, 2017 10:30 am
by Coleen_Leslie_2L
Will quizzes be returned in discussion sections this week?

Re: Quiz 3 Winter 2017

Posted: Mon Mar 13, 2017 4:54 pm
by Chem_Mod
Coleen_Leslie_2L wrote:Will quizzes be returned in discussion sections this week?


Yes

Re: Quiz 3 Winter 2017

Posted: Tue Mar 14, 2017 6:10 pm
by tpat14
If a a reaction is at equilibrium is it always the limiting reactant because it's slower? Or is it faster and the other is limiting?

Re: Quiz 3 Winter 2017

Posted: Wed Mar 15, 2017 1:12 pm
by TiengTum2D
Julie Barreto 3A wrote:how would you draw out 2-butene or anything with a number in front of it ???


In that case, the 2 simply indicate the location of the double bond. So the double would be between the 2nd and 3rd carbon in your carbon chain drawing.

Re: Quiz 3 Winter 2017

Posted: Thu Mar 16, 2017 10:27 am
by vannahyazon 1L
Chris_Rudewicz_3H wrote:We still get to drop our lowest quiz score, right?


Your lowest quiz score will be replaced by your highest quiz score.

So your grade for quizzes should be:

1. HIGHEST SCORE
2. HIGHEST SCORE
3. MIDDLE SCORE

Re: Quiz 3 Winter 2017

Posted: Thu Mar 16, 2017 12:58 pm
by Samantha Rubin-Pope - 1H
When will our quiz 3 scores be posted to MyUCLA?

Re: Quiz 3 Winter 2017

Posted: Thu Mar 16, 2017 11:11 pm
by veeksha25
Iso is needed whenever you have a methyl connected to "two carbons" (methyl connected to a carbon which is connected to another carbon)

Re: Quiz 3 Winter 2017

Posted: Fri Mar 17, 2017 1:06 am
by Armani Dodson 1A
Where are the answers for the actual quiz 3 posted.

Re: Quiz 3 Winter 2017

Posted: Fri Mar 17, 2017 1:10 am
by Armani Dodson 1A
How do you get the pseudo equilibrium constant on quiz 3?

Re: Quiz 3 Winter 2017

Posted: Fri Mar 17, 2017 3:11 pm
by Diana_Anum1G
Armani Dodson 1A wrote:How do you get the pseudo equilibrium constant on quiz 3?

Transition state over reactants.