Search found 33 matches
- Fri Mar 17, 2017 9:47 am
- Forum: *Electrophilic Addition
- Topic: Electrophilic Addition
- Replies: 2
- Views: 1450
Re: Electrophilic Addition
Since this is not part of 14B syllabus, I doubt it would make a difference which Carbon you attach the Halide to. The question usually specifies the product formed, so just follow that. This is how it works --> ASYMMETRIC ACROSS DOUBLE BOND - both carbons have different number of hydrogens attached ...
- Wed Mar 15, 2017 11:35 pm
- Forum: *Cycloalkanes
- Topic: Numbering counterclockwise or clockwise
- Replies: 4
- Views: 8666
Re: Numbering counterclockwise or clockwise
The priority goes --
Functional Groups > Bonds (triple>double) > substituents.
So you would choose a numbering such that the functional group gets the lowest value.
Functional Groups > Bonds (triple>double) > substituents.
So you would choose a numbering such that the functional group gets the lowest value.
- Wed Mar 15, 2017 9:03 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Flipping an Ecell equation
- Replies: 1
- Views: 660
Re: Flipping an Ecell equation
E 0 cell = E 0 cathode - E 0 anode For a Spontaneous (favorable) cell E 0 cell is positive. So if both reduction reactions are given, try plugging the values into the equation above to see which combination gives you a positive value. The combination giving the positive value will tell you which rea...
- Wed Mar 15, 2017 8:56 pm
- Forum: *Cyclohexanes (Chair, Boat, Geometric Isomers)
- Topic: How to determine higher stability
- Replies: 2
- Views: 1631
Re: How to determine higher stability
Chloro and Bromo groups are large in size. Hence if they are placed close to each other, they will experience very high repulsion (ie the structure is unstable). They also experience repulsion from the hydrogen groups. To minimize the repulsion, thereby making the structure stable, these two groups ...
- Tue Mar 14, 2017 11:07 pm
- Forum: *Cycloalkanes
- Topic: Numbering counterclockwise or clockwise
- Replies: 4
- Views: 8666
Re: Numbering counterclockwise or clockwise
The first priority of numbering is given to the alkene group, that is the double bond. While numbering the carbons, we always go along the double bond. So in this case, we choose the lowest number for the carbon with the double bond, with the Cl group attached to it. This makes our double bond and o...
- Tue Mar 14, 2017 10:56 pm
- Forum: *Alkanes and Substituted Alkanes (Staggered, Eclipsed, Gauche, Anti, Newman Projections)
- Topic: Angle of 60/180 or 0 and 120
- Replies: 3
- Views: 1043
Re: Angle of 60/180 or 0 and 120
I drew them out below.
The dihedral angle is between the Chloro and the Bromo groups.
Hope this helps.
The dihedral angle is between the Chloro and the Bromo groups.
Hope this helps.
- Tue Mar 14, 2017 12:09 pm
- Forum: *Cycloalkanes
- Topic: Benzene [ENDORSED]
- Replies: 3
- Views: 1933
Re: Benzene [ENDORSED]
Oh... I'm so sorry.
Yes.
Amines too.
Yes.
Amines too.
- Tue Mar 14, 2017 11:56 am
- Forum: *Haloalkanes
- Topic: Practice Problem Sets [ENDORSED]
- Replies: 1
- Views: 1280
Re: Practice Problem Sets [ENDORSED]
Naming structures with multiple double bonds follows the same principle as all other compounds. There is however, one small difference -- You retain the 'a' after the prefix (indicating the number of carbons) and put di, tri .... to indicate how many double bonds there are. For Example - CH 2 =CH-CH...
- Tue Mar 14, 2017 11:49 am
- Forum: *Cycloalkanes
- Topic: Benzene [ENDORSED]
- Replies: 3
- Views: 1933
Re: Benzene [ENDORSED]
Dr. Lavelle hasn't covered benzene as a substituent in class. So, the questions assigned for homework also neglect the larger benzene problems. When benzene is the main ring, then you just write benzene For example - Chloro Benzene 1,2 Dichloro Benzene (orthodichlorobenzene) etc.. It is written as a...
- Tue Mar 14, 2017 11:40 am
- Forum: *Alkanes and Substituted Alkanes (Staggered, Eclipsed, Gauche, Anti, Newman Projections)
- Topic: Angle of 60/180 or 0 and 120
- Replies: 3
- Views: 1043
Re: Angle of 60/180 or 0 and 120
You could draw the same structure if all the atoms bound to both the carbons are the same. For example - Ethane Or even if all were the same except one. For example - Bromo- ehtane However, when there are different groups around the carbons, say a Bromine (bromo), on one of the carbons, and Chlorine...
- Fri Mar 10, 2017 9:30 am
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 2762323
Re: Post All Chemistry Jokes Here
1st Chemist: "What's new?"
2nd Chemist: c over lambda.
2nd Chemist: c over lambda.
- Fri Mar 10, 2017 9:18 am
- Forum: *Amines
- Topic: Numbering of carbons in amines
- Replies: 1
- Views: 1215
Numbering of carbons in amines
In amine compounds with multiple hydrocarbon substituents (2 or 3), if one of them has a substituent, which direction do we start naming it in. Should the Carbon attached to the Nitrogen get the lowest number (1) or should we try to make the substituent get the lowest number?
- Fri Mar 03, 2017 11:15 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Extra Review Session Winter 2017
- Replies: 7
- Views: 2177
Re: Extra Review Session Winter 2017
Please find attached the recording of winter 2017 post midterm review
- Fri Mar 03, 2017 9:30 am
- Forum: *Alkanes
- Topic: Naming Organic Compounds (substituents)
- Replies: 1
- Views: 580
Naming Organic Compounds (substituents)
How to name an organic compound that has a hydrocarbon chain with substituents as a substituent. eg - CH3-CH-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH3 | H-C-H H-C-H H-C-H H-C-Br H-C-H H For some reason, this post shows the substituent attached to the 1st carbon. It is attached to the second Carbon.
- Sat Feb 25, 2017 11:38 am
- Forum: *Enzyme Kinetics
- Topic: Catalyst [ENDORSED]
- Replies: 2
- Views: 588
Catalyst [ENDORSED]
Are catalysts included in the overall rate law of a reaction?
- Fri Feb 17, 2017 9:19 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 2762323
Re: Post All Chemistry Jokes Here
Chemistry Lab.
- Fri Feb 17, 2017 9:11 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 2762323
Re: Post All Chemistry Jokes Here
I have many chemistry jokes.
....
I'm just afraid they won't get a good Reaction.
....
I'm just afraid they won't get a good Reaction.
- Thu Feb 09, 2017 12:38 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Delta G vs Delta G0
- Replies: 5
- Views: 7784
Delta G vs Delta G0
When asked for delta G, being given Delta H0 and Delta S0, should we just plug in the given temperature (Delta G0 = DeltaH0 - T DeltaS0) or
calculate Delta G using -
Delta G = DeltaG0 + RT ln(Q) <Where DeltaG0 = DeltaH0 - (298)DeltaS0>
????
calculate Delta G using -
Delta G = DeltaG0 + RT ln(Q) <Where DeltaG0 = DeltaH0 - (298)DeltaS0>
????
- Mon Feb 06, 2017 7:18 pm
- Forum: Interesting Applications: Rechargeable Batteries (Cell Phones, Notebooks, Cars), Fuel Cells (Space Shuttle), Photovoltaic Cells (Solar Panels), Electrolysis, Rust
- Topic: Half reactions for electrolysis [ENDORSED]
- Replies: 1
- Views: 538
Half reactions for electrolysis [ENDORSED]
How is writing half reactions for electrolysis different from electrolytic cells?
We only have one solution, so how do we go abut doing that?
We only have one solution, so how do we go abut doing that?
- Wed Feb 01, 2017 10:58 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Salt Bridge?
- Replies: 3
- Views: 559
Re: Salt Bridge?
The salt bridge completes the circuit hence allowing current to pass through the system. The wires allow movement of electrons. The salt bridge allows movement of counter ions from one side to the other.
- Tue Jan 24, 2017 1:32 pm
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: Energy of a Gas?
- Replies: 2
- Views: 625
Energy of a Gas?
Do we have to prove or remember the proofs for
Energies of ideal gases - (mono atomic - 3/2 nRT and diatomic - 5/2 nRT)?
When do we use these in thermodynamics?
Energies of ideal gases - (mono atomic - 3/2 nRT and diatomic - 5/2 nRT)?
When do we use these in thermodynamics?
- Fri Jan 20, 2017 11:34 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Work on or by the system? [ENDORSED]
- Replies: 1
- Views: 509
Work on or by the system? [ENDORSED]
If the sign of Delta H is negative, is the work being done on the system or by the system/
- Fri Jan 13, 2017 7:24 am
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Units of Reaction Enthalpies
- Replies: 11
- Views: 2053
Re: Units of Reaction Enthalpies
But what if the product generated is not one mole in quantity?
Or if there are multiple products? (so multiple moles of each)
Or if there are multiple products? (so multiple moles of each)
- Thu Jan 12, 2017 6:08 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Units of Reaction Enthalpies
- Replies: 11
- Views: 2053
Units of Reaction Enthalpies
When we calculate reaction enthalpies for reaction that have more than one product or the balanced reaction has multiple moles of a product; what unit should we use?
Should we write kJ/mol or just kJ (since there are multiple moles)?
Should we write kJ/mol or just kJ (since there are multiple moles)?
- Fri Dec 02, 2016 2:09 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 2762323
Re: Post All Chemistry Jokes Here
What do you call a fish made of two sodium atoms?
2Na
2Na
- Fri Dec 02, 2016 1:54 pm
- Forum: *Making Buffers & Calculating Buffer pH (Henderson-Hasselbalch Equation)
- Topic: Making a buffer through titration [ENDORSED]
- Replies: 1
- Views: 495
Making a buffer through titration [ENDORSED]
During titration, how do we calculate the amount of base or acid required to make a buffer of a desired pH?
- Tue Nov 22, 2016 4:26 pm
- Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
- Topic: Percentage dissociation
- Replies: 1
- Views: 481
Percentage dissociation
What happens if percentage of dissociation is greater than 5%? Does it make all our calculations and approximation of (m-x=m) wrong?
Can we not use this if t is greater than 5%?
Can we not use this if t is greater than 5%?
- Tue Nov 22, 2016 4:20 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 2762323
Re: Post All Chemistry Jokes Here
A neutron walks into a bar and asks how much for a drink. The bartender replies "For you, No Charge."
- Thu Nov 17, 2016 4:53 pm
- Forum: Amphoteric Compounds
- Topic: With respect to other compounds....
- Replies: 1
- Views: 725
With respect to other compounds....
Amphoteric substances behave as either acids or bases in different situations. So I assume that their nature depends on the other compounds they interact with.
What happens when we study these compounds individually? Are they acidic or basic, or neither?
What happens when we study these compounds individually? Are they acidic or basic, or neither?
- Sat Nov 12, 2016 10:55 am
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Aqueous Ions
- Replies: 1
- Views: 414
Aqueous Ions
While calculating K, why do we consider only gases?
We don't consider liquid and solids, but why do we consider aqueous ions?
We don't consider liquid and solids, but why do we consider aqueous ions?
- Wed Nov 02, 2016 11:09 am
- Forum: Dipole Moments
- Topic: Net Dipole Moment
- Replies: 1
- Views: 937
Net Dipole Moment
How to determine if a compound has a net dipole moment or not? What factors is the net dipole moment based on?
- Sat Oct 22, 2016 2:30 pm
- Forum: Electronegativity
- Topic: Electronegativity vs Electron Affinity
- Replies: 4
- Views: 1585
Electronegativity vs Electron Affinity
How is Electronegativity different from electron affinity?
Why does Electron affinity have a unit?
Why doesn't Electronegativity have a unit?
Why does Electron affinity have a unit?
Why doesn't Electronegativity have a unit?
- Thu Oct 13, 2016 12:11 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: s and d orbitals
- Replies: 3
- Views: 803
s and d orbitals
While writing the electronic configurations, we fill up orbitals from lowest to highest energy. For K and Ca we write the [Ar]4s (4s1 and 4s2). However, the next element, Sc , we write 3d before 4s. Is this the standard convention or does the energy of the 4s orbital increase due to the presence of ...