Search found 16 matches

by Andre Tsivis 1K
Sat Mar 12, 2016 2:00 am
Forum: *Cycloalkenes
Topic: Final 2012 Question 5
Replies: 1
Views: 407

Re: Final 2012 Question 5

A ring structure has the carbons on the inside of each bond. When a double bond locks it into place, the ring forms bonds on the same side of the bond and not on opposite sides. A ring that has a trans structure is often unstable and irregulary looking. All circular rings will have a cis structure.
by Andre Tsivis 1K
Thu Mar 10, 2016 2:45 am
Forum: Student Social/Study Group
Topic: Post All Chemistry Jokes Here
Replies: 8017
Views: 1401872

Re: Chemistry Jokes

After chemistry class, a student asks a chemist for help with regards to rate constants. The chemist, in response says "k" !
by Andre Tsivis 1K
Fri Mar 04, 2016 5:32 pm
Forum: *Constitutional and Geometric Isomers (cis, Z and trans, E)
Topic: Priority Groups
Replies: 1
Views: 323

Re: Priority Groups

If two groups are the same, it would mean that both chains would have exactly the same formula, therefore, it would be labeled as a dichloro (for your example) or (something like )a diethyl group. Because of this, priority would not matter because the chains would be equal anyways. In the regards of...
by Andre Tsivis 1K
Fri Feb 26, 2016 1:21 pm
Forum: *Cycloalkenes
Topic: Numbering for Cycloalkenes
Replies: 2
Views: 633

Re: Numbering for Cycloalkenes

Also, the length of the substituent doesn't matter, only the placement does. A methyl group holds the same numbering priority as a larger substituting such as an isopropyl or tert-pentyl group. But as always, this ordering still has a lower priority than making the double bonds as low of a number as...
by Andre Tsivis 1K
Fri Feb 26, 2016 1:16 pm
Forum: *Cycloalkenes
Topic: Numbering for Cycloalkenes
Replies: 2
Views: 633

Re: Numbering for Cycloalkenes

Double bonds hold priority. The best way to name cycloalkenes is to have the double bonds have priority over the substituents. However, the double bond with the most substituants directly in front of it should get the lower number, hence making the most substituent groups have lower numbers. Of cour...
by Andre Tsivis 1K
Sun Feb 21, 2016 2:55 am
Forum: *Organic Reaction Mechanisms in General
Topic: Arrow Electron Flow Ex from Course Reader
Replies: 2
Views: 393

Re: Arrow Electron Flow Ex from Course Reader

I am also assuming that when a BOND is broken, 2 e- will be transferred and when there is just a single dot drawn in the Lewis structure then only that one e- will be transferred.
by Andre Tsivis 1K
Sun Feb 21, 2016 2:13 am
Forum: *Organic Reaction Mechanisms in General
Topic: Arrow Electron Flow Ex from Course Reader
Replies: 2
Views: 393

Re: Arrow Electron Flow Ex from Course Reader

2 electrons are being transferred if there is a double-headed arrow, and only one electron is being transferred if there is a single-headed arrow (pg. 86 course reader).
by Andre Tsivis 1K
Sun Feb 21, 2016 2:00 am
Forum: Arrhenius Equation, Activation Energies, Catalysts
Topic: k and rate of reaction
Replies: 1
Views: 354

Re: k and rate of reaction

To find a rate, a specific reaction must be given, from which a rate law can be established. Then a k value must be found by by using the Arrhenius equation and then it can be related back into the Rate law derived from a given reaction.
by Andre Tsivis 1K
Sat Feb 13, 2016 2:33 am
Forum: Reaction Mechanisms, Reaction Profiles
Topic: Rate law
Replies: 2
Views: 401

Re: Rate law

A rate law explains the rate of reactions according to parameters given. A differential rate law is helpful for explaining the rate at a certain time. The integrated rate law is helpful for finding a time where an amount of material exists and the 1/2 life laws help to explain half lives. All use co...
by Andre Tsivis 1K
Fri Feb 05, 2016 12:45 am
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: How to figure out Cathode and Anode Reactions?
Replies: 1
Views: 324

Re: How to figure out Cathode and Anode Reactions?

Oxidation occurs when a substance loses an electron. Therefore the charge increases. Reduction occurs where a substance gains an electron and reduces a substance's chemical charge. The half reactions show oxidation and reduction separately, both balanced seperately so that all of the e- cancel out o...
by Andre Tsivis 1K
Thu Jan 28, 2016 6:32 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Bond Enthalpies
Replies: 3
Views: 518

Bond Enthalpies

For some reason I can never do these problems properly. For bond enthalpies, do the broken bonds have their values negated or do the formed bonds have their enthalphy negated? Sorry if it's a dumb question but thank you in advance everyone.
by Andre Tsivis 1K
Tue Jan 26, 2016 5:29 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Elements in their most stable form
Replies: 2
Views: 6171

Re: Elements in their most stable form

An element is in its most stable form if it is in its most pure/stable state (For example Fe(s), Na(s), He(g), H2(g), C(s) are all n their elemental forms). In liquid and solid forms, an elemental state is a pure block or substance containing only that element (like a block of pure iron, or a block ...
by Andre Tsivis 1K
Fri Jan 22, 2016 3:35 am
Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
Topic: Reversible and Irreversible
Replies: 1
Views: 349

Re: Reversible and Irreversible

A reversible process is one that takes place in equilibrium and is a slow gradual change from one position to the next. Because it is a continuous change, it can be reversed with an opposite reaction. On the contrary, irreversible processes occur when there is a spontaneous action of some sort such ...
by Andre Tsivis 1K
Fri Jan 15, 2016 12:16 am
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: Heat Capacity
Replies: 3
Views: 477

Re: Heat Capacity

I find Heat Capacity as being still useful even though it is an extensive property because it can be used to derive other more specific heat capacities. By placing a mass measure to the extensive property of Heat Capacity, other specific heat capacities can be derived according to the mass measure t...
by Andre Tsivis 1K
Fri Jan 08, 2016 1:51 am
Forum: Phase Changes & Related Calculations
Topic: +VE and phase change
Replies: 2
Views: 1240

+VE and phase change

I am a little unsure of what the term "+VE" (Course reader Pg 17) means. Also, if VE+ is the result of endothermic reactions, could the term change to be negative in the case of exothermic state changes (e.g. freezing/condensation/deposition), or does state change only yield a positive VE+...

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