Search found 20 matches
- Wed Nov 30, 2016 8:09 pm
- Forum: *Titrations & Titration Calculations
- Topic: Hwk 13.29
- Replies: 5
- Views: 3417
Re: Hwk 13.29
Haha awesome, thank you!
- Tue Nov 29, 2016 3:30 pm
- Forum: *Titrations & Titration Calculations
- Topic: Hwk 13.29
- Replies: 5
- Views: 3417
Hwk 13.29
1.436g of NaOH is dissolved in 300.mL solution, 25.00mL of this solution is titrated to the stoichiometric point with 34.20mL of 0.0695 M HCl. What is the percentage purity of the original sample? 1. I converted g of NaOH to moles of NaOH. 2. I then converted 0.0695M HCl to moles of HCl. 3. I then d...
- Mon Nov 28, 2016 8:09 pm
- Forum: *Making Buffers & Calculating Buffer pH (Henderson-Hasselbalch Equation)
- Topic: Henderson-Hasselbalch equation
- Replies: 4
- Views: 1839
Re: Henderson-Hasselbalch equation
The Henderson-Hasselbalch equation is used to calculate the pH of solution containing an acid and its conjugate base as a salt OR to calculate the pOH of a base and its conjugate acid as a salt.
pH= pKa + log(A-/HA)
pOH= pKb + log(BH+/BH)
pH= pKa + log(A-/HA)
pOH= pKb + log(BH+/BH)
- Wed Nov 16, 2016 4:58 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 3686939
Re: Post All Chemistry Jokes Here
If you’re not part of the solution your part of the precipitate.
- Wed Nov 16, 2016 4:58 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 3686939
Re: Post All Chemistry Jokes Here
What does a chemist bring as a dessert while camping? A ‘gram’ cracker.
- Wed Nov 09, 2016 9:49 pm
- Forum: Ideal Gases
- Topic: Quiz 3 [ENDORSED]
- Replies: 2
- Views: 812
Re: Quiz 3 [ENDORSED]
I think everything covered in the Course Reader would be fair game for the quiz.
- Mon Nov 07, 2016 11:58 pm
- Forum: Ionic & Covalent Bonds
- Topic: Cation vs Anion
- Replies: 4
- Views: 2797
Re: Cation vs Anion
Also, just to add on, cations are smaller than anions and have a positive charges.
- Tue Nov 01, 2016 11:35 pm
- Forum: Photoelectric Effect
- Topic: 2015 Midterm Question #3
- Replies: 2
- Views: 1015
Re: 2015 Midterm Question #3
In order to use the kinetic equation you would need 2 of the 3 things: the energy of the photons being emitted onto the metallic surface, the threshold energy of the metallic surface, or the kinetic energy of the photons emitted(1/2mv^2). According to the De Broglie equation, Wave Length= h/p and p=...
- Tue Nov 01, 2016 11:25 pm
- Forum: Hybridization
- Topic: hybridization
- Replies: 2
- Views: 593
Re: hybridization
Px and Py form pi bonds. Pz forms sigma bonds. Elaborate on the first part of your question.
Thanks.
Thanks.
- Tue Nov 01, 2016 11:21 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Fall 2015 Midterm Question 4
- Replies: 1
- Views: 734
Re: Fall 2015 Midterm Question 4
Hi Katelyn! The electron arrangement assumes the shape trigonal bipyramidal, however, when we take into account the 3 lone pairs, the molecular shape is in fact linear. To see this more clearly, imagine a linear molecule(2 atoms on each end) and arrange the 3 lone pairs around the central atom. I wi...
- Tue Nov 01, 2016 10:28 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Lone pairs in polarity
- Replies: 1
- Views: 476
Re: Lone pairs in polarity
Yes, lone pairs affect the polarity of a molecule. If there is an individual lone pair, there won't be another pair of electrons to cancel out the dipole moment, therefore the molecule will be polar. If there are two lone pairs, it is possible for it to not affect the polarity of the molecule if the...
- Mon Oct 31, 2016 10:41 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Lone Pairs on Linear Molecule
- Replies: 3
- Views: 1580
Re: Lone Pairs on Linear Molecule
Actually, after researching it appears that a molecule with AX2E3 is a linear molecule. Take I3- for example.
- Mon Oct 31, 2016 10:33 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Lone Pairs on Linear Molecule
- Replies: 3
- Views: 1580
Lone Pairs on Linear Molecule
Can a molecule have lone pairs and still be linear? Wouldn't AX2E1 or AX2E2 be Bent Shape? Thanks for the help.
- Sun Oct 30, 2016 11:10 pm
- Forum: Lewis Structures
- Topic: (SO3)2- Lewis Structure Formal Charge
- Replies: 1
- Views: 13233
(SO3)2- Lewis Structure Formal Charge
Hi. The Lewis Structure for sulfite has 3 resonance structures in which the Sulfur has a formal charge of 0 and two of the oxygens have a formal charge of -1. Why couldn't there be a 3 double bonds instead? Wouldn't this contribute to Sulfur having a formal charge of -2 and the oxygens having a form...
- Mon Oct 24, 2016 9:45 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: S, P, D, and F Orbitals [ENDORSED]
- Replies: 4
- Views: 1181
Re: S, P, D, and F Orbitals [ENDORSED]
An orbital is a mathematical representation of where an electron is likely to be found. Each orbital can hold up to two electrons with opposite spins. These orbitals are found in subshells(s,p,d,f) and the subshells are found in different energy levels(n).
- Tue Oct 18, 2016 9:08 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Aufbau's Principle [ENDORSED]
- Replies: 3
- Views: 836
Re: Aufbau's Principle [ENDORSED]
This is true for nearly all atoms with two exceptions: chromium and copper. I'd urge you to refer to the final paragraph of page 46 in the textbook as it would give a fairly thorough response as to why the exceptions exist. Hope this helped!
- Mon Oct 17, 2016 4:30 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Aufbau's Principle [ENDORSED]
- Replies: 3
- Views: 836
Re: Aufbau's Principle [ENDORSED]
Once they contain electrons, the 3d orbitals have lower energy than the 4s orbitals. Therefore, the 3d orbital must come before the 4s orbital.
- Mon Oct 10, 2016 7:17 pm
- Forum: Properties of Light
- Topic: Rydberg Equation
- Replies: 5
- Views: 1316
Re: Rydberg Equation
Both can be used: the latter is just a simplified version.
- Tue Oct 04, 2016 3:49 pm
- Forum: Properties of Light
- Topic: C=λV units question
- Replies: 3
- Views: 2367
Re: C=λV units question
Wavelength must always be calculated or used in a calculation in meters.
- Thu Sep 29, 2016 11:49 pm
- Forum: Properties of Light
- Topic: Frequency, wavelength, and Energy of light
- Replies: 5
- Views: 1019
Re: Frequency, wavelength, and Energy of light
What is the difference between the "energy" and "intensity" of a wave? Or are they referring to the same point in mind?