Search found 29 matches
- Sat Mar 18, 2017 7:55 pm
- Forum: *Alkenes
- Topic: Are alkenes and alkynes considered functional groups?
- Replies: 4
- Views: 1672
Re: Are alkenes and alkynes considered functional groups?
This confused me too because on Q5A. on the 2013 final alkene was considered a functional group but not on 2015 Q10? So I don't get whether or not it is..
- Fri Mar 17, 2017 2:52 am
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: Catalyst that is used and produced
- Replies: 4
- Views: 872
Re: Catalyst that is used and produced
Do you include the catalyst when writing the rate law?
- Thu Mar 16, 2017 11:18 pm
- Forum: *Electrophilic Addition
- Topic: Transition step
- Replies: 3
- Views: 1609
Re: Transition step
But then if the first step's activation energy is lower than the second steps then why wouldn't it be the second step?
- Thu Mar 16, 2017 11:17 pm
- Forum: *Electrophilic Addition
- Topic: Electrophilic Addition Example in Quiz 3 Prep
- Replies: 2
- Views: 1369
Re: Electrophilic Addition Example in Quiz 3 Prep
Also, for these reactions it will be a pi bond breaking to form two sigma bonds.
- Thu Mar 16, 2017 11:11 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Quiz 3 Winter 2017
- Replies: 183
- Views: 30191
Re: Quiz 3 Winter 2017
Iso is needed whenever you have a methyl connected to "two carbons" (methyl connected to a carbon which is connected to another carbon)
- Thu Mar 16, 2017 11:06 pm
- Forum: *Organic Reaction Mechanisms in General
- Topic: Naming Organic Molecules
- Replies: 20
- Views: 4232
Re: Naming Organic Molecules
When you name cyclohexenes, can you go clockwise or counterclockwise in numbering carbons? And also, what role does the double bond play in numbering?
Re: "Iso"
Building on the previous replies, it may be useful to know that iso- prefixes generally occur when the substituent is on the second carbon in the parent chain.
- Fri Mar 10, 2017 2:20 pm
- Forum: *Alkanes
- Topic: Naming [ENDORSED]
- Replies: 93
- Views: 17169
Re: Naming [ENDORSED]
If there are two methyls, for example, on Carbon number 2; then you would write it as 2-dimethyl. Similarly, if it was on Carbon #3, it would be 3-dimethyl.
- Fri Mar 10, 2017 2:19 pm
- Forum: *Organic Reaction Mechanisms in General
- Topic: Naming Organic Molecules
- Replies: 20
- Views: 4232
Re: Naming Organic Molecules
The Khan Academy ones helped me a lot, especially when it came to naming alkenes and alkynes with iso- and sec- etc. prefixes, it was really helpful.
- Wed Feb 22, 2017 2:32 pm
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: Arrhenius plot vs. activation energy
- Replies: 3
- Views: 1136
Re: Arrhenius plot vs. activation energy
If the slope of the line is steeper does that mean that it has a higher or lower activation energy?
- Wed Feb 22, 2017 2:30 pm
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: Ea and rate constant
- Replies: 3
- Views: 812
Re: Ea and rate constant
I've been a little confused on what k can be affected by because it is a constant. Is it affected by temperature, concentrations, and catalysts? Or are there more factors besides this?
- Wed Feb 22, 2017 2:26 pm
- Forum: General Science Questions
- Topic: Rusty on High School Chem [ENDORSED]
- Replies: 347
- Views: 479341
Re: Rusty on High School Chem [ENDORSED]
I had the same issue and I've been using Tyler Dewitt's videos (: I'm a very visual learner so they really helped me out, especially during the thermochemistry unit.
- Wed Feb 22, 2017 2:24 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 3977248
Re: Post All Chemistry Jokes Here
Why do scientists call helium, curium, and barium the healing elements?
Because if you can't helium or curium, you have to barium
Because if you can't helium or curium, you have to barium
- Thu Feb 09, 2017 7:00 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 3977248
Re: Post All Chemistry Jokes Here
Why did the bear dissolve in water?
Because it was polar lol
Because it was polar lol
- Thu Feb 02, 2017 11:28 pm
- Forum: Concepts & Calculations Using Second Law of Thermodynamics
- Topic: Entropy Integral
- Replies: 1
- Views: 533
Entropy Integral
A few of the problems use the integral of Cp dt/T and i'm confused as to what that is equal to; is it equal to entropy or enthalpy?
- Thu Jan 26, 2017 5:18 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 3977248
Re: Post All Chemistry Jokes Here
Why do chemists like nitrates so much?
They're cheaper than day rates.
They're cheaper than day rates.
- Wed Jan 18, 2017 11:59 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Help on Problem 8.25
- Replies: 1
- Views: 403
Help on Problem 8.25
In this problem, the heat gained by the reaction is that which is lost by the calorimeter, which made sense. But in the solutions manual when calculating q for the calorimeter in q=mCdt; the book only multiplies the C and the dt; what happens to the m?
- Sun Jan 15, 2017 11:14 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 3977248
Re: Post All Chemistry Jokes Here
I asked the guy sitting next to me if he had any Sodium Hypobromite…
He said NaBrO
He said NaBrO
- Mon Nov 28, 2016 10:40 pm
- Forum: Properties of Electrons
- Topic: Wavelength and Diameter
- Replies: 1
- Views: 616
Wavelength and Diameter
On one of the practice finals, it asks "Given that the diameter of a helium atom is approximately 10^-10 m; does your answer make sense?" And the answer is "since the wavelength is less than the diameter, yes it makes sense." I don't remember reading about this, is this a princip...
- Wed Nov 23, 2016 8:30 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 3977248
Re: Post All Chemistry Jokes Here
If a bear in Yosemite and a bear in Alaska both fell in water, which one would dissolve faster?
The one from Alaska, it's polar
The one from Alaska, it's polar
- Mon Nov 21, 2016 10:22 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 3977248
Re: Post All Chemistry Jokes Here
Two chemists go into a bar. The first one says "I think I'll have an H2O." The second one says "I think I'll have an H2O too" — and he died.
- Thu Nov 17, 2016 1:58 pm
- Forum: Naming
- Topic: Polydentates
- Replies: 4
- Views: 998
Polydentates
For carbonato, why is the molecule a bidentate and not a tetradentate even though there are four oxygens with lone pairs available for bonding?
- Thu Nov 10, 2016 6:58 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 3977248
Re: Post All Chemistry Jokes Here
Q: When one physicist asks another, "What's new?" what's the typical response?
A:C over lambda.
A:C over lambda.
- Fri Nov 04, 2016 1:06 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Shapes
- Replies: 6
- Views: 1151
Re: Shapes
Yes, we do. The lone pairs are vital in determining VSEPR shapes because the repulsion causes a change in shape, and thus, bond angle. For example, many molecules have bond angles of "less than" (180, for example) because even though the atoms may seem to be 180 degrees apart, in reality t...
- Fri Nov 04, 2016 1:06 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Shapes
- Replies: 6
- Views: 1151
Re: Shapes
Yes, we do. The lone pairs are vital in determining VSEPR shapes because the repulsion causes a change in shape, and thus, bond angle. For example, many molecules have bond angles of "less than" (180, for example) because even though the atoms may seem to be 180 degrees apart, in reality t...
- Sat Oct 22, 2016 7:42 pm
- Forum: SI Units, Unit Conversions
- Topic: Sig Figs [ENDORSED]
- Replies: 16
- Views: 3298
Re: Sig Figs [ENDORSED]
If a number is written in scientific notation with a zero, for example 5.60*10^4, then does only the one 0 count as significant or would it have 3 significant zeros because of the 10^4?
- Fri Oct 14, 2016 7:04 pm
- Forum: Ionic & Covalent Bonds
- Topic: Ionic Vs Covalent bonds
- Replies: 4
- Views: 1063
Re: Ionic Vs Covalent bonds
The type of bond depends on how big the electronegativity difference is between the two atoms. A smaller difference in electronegativity is generally a covalent bond, whereas a larger difference is an ionic bond. Above 2.0 difference between the to bonding atoms leads to an ionic bond and below lead...
- Fri Oct 07, 2016 7:15 pm
- Forum: General Science Questions
- Topic: Mass of an electron
- Replies: 3
- Views: 1260
Re: Mass of an electron
Binding energy is the energy that bounds the electron to the metal. The threshold energy is the minimum energy necessary to eject an electron from the metal surface.
- Fri Sep 30, 2016 7:55 pm
- Forum: Significant Figures
- Topic: Basic Sig Figs
- Replies: 13
- Views: 2004
Re: Basic Sig Figs
Trailing zeros, as well as leading zeros, both don't count as significant figures because they are simply placeholders in the number. However, if there is a decimal, then the zeros do count as significant. For example, 400 has only one significant figure because the zeros are just placeholders; but ...