Search found 33 matches
- Sat Dec 08, 2018 3:28 pm
- Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
- Topic: Usuing Rydberg's Equation Conceptually
- Replies: 1
- Views: 519
Usuing Rydberg's Equation Conceptually
For Rydberg's equation, I have seen in previous threads that the negative means that the there is a decrease in energy. So, should I proceed with the problem with the negative from the formula or add the negative in the end. For example, if I am trying to find the energy emitted from when the level ...
- Fri Dec 07, 2018 9:31 pm
- Forum: Lewis Acids & Bases
- Topic: HCl vs. HI
- Replies: 7
- Views: 731
Re: HCl vs. HI
I think bond length and electronegativity are directly related since the more electronegative an ion is, the shorter the bond length, the less acidic it is.
- Fri Dec 07, 2018 5:47 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Correct Bond Angles
- Replies: 6
- Views: 652
Re: Correct Bond Angles
The angles of molecules with lone pair electrons always push the other bonds out of place and closer together, thus the bond angles are smaller in such situations.
- Thu Dec 06, 2018 3:30 pm
- Forum: General Science Questions
- Topic: Studying Methods
- Replies: 6
- Views: 1022
Studying Methods
How would anyone recommend studying for the final? Would videos on youtube or practice questions be better practice?
- Sun Dec 02, 2018 6:30 pm
- Forum: Properties & Structures of Inorganic & Organic Bases
- Topic: Soapy Feels
- Replies: 4
- Views: 760
Re: Soapy Feels
They react with the acidic outside of our skin.
- Tue Nov 27, 2018 12:33 pm
- Forum: Hybridization
- Topic: How to Write Second Pi Bond in Triple Bond
- Replies: 3
- Views: 441
Re: How to Write Second Pi Bond in Triple Bond
Olivia L 3D wrote:I just asked my TA this today and he said it would be (Cp -Cp) because they are the same type of bond. The compositions are the same but there are more than one.
Thanks!
- Tue Nov 27, 2018 10:06 am
- Forum: Hybridization
- Topic: How to Write Second Pi Bond in Triple Bond
- Replies: 3
- Views: 441
How to Write Second Pi Bond in Triple Bond
For example, in acetylene (C2H2) there is a triple bond between the two carbons. So, the sigma bond is (Csp - H1) for both carbons to hydrogens (since the shape is linear). For the first sigma bond between the two carbons it would be (Csp - Csp) and for the first pi bond it would be (Cp - Cp). Howev...
- Sun Nov 25, 2018 6:46 pm
- Forum: Interionic and Intermolecular Forces (Ion-Ion, Ion-Dipole, Dipole-Dipole, Dipole-Induced Dipole, Dispersion/Induced Dipole-Induced Dipole/London Forces, Hydrogen Bonding)
- Topic: induced-dipole
- Replies: 4
- Views: 670
Re: induced-dipole
A dipole occurs when there is one side of the atom that is more electronegative than the other. However, an induced-dipole occurs when a non-polar molecule interacts with a dipole and since there is a preference for electronegativity on one side of the dipole, the non-polar molecule will shift its e...
- Sun Nov 25, 2018 6:43 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Test 3 material
- Replies: 6
- Views: 700
Re: Test 3 material
My TA mentioned that it would be all material from after the midterm to last friday.
- Sun Nov 25, 2018 6:41 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Sigma vs pi bonds
- Replies: 7
- Views: 728
Re: Sigma vs pi bonds
Think of sigma bonds being the inital bond between two molecules and every additional bond being a pi bond.
- Sun Nov 18, 2018 9:48 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Bond Angles Between the Same shape
- Replies: 6
- Views: 650
Bond Angles Between the Same shape
Will the bond angles be the same for all bent VESPR shapes or does electron affinity or density play a role on the bond angle?
- Sun Nov 18, 2018 9:45 pm
- Forum: Properties of Light
- Topic: Test 3
- Replies: 24
- Views: 2113
Re: Test 3
Lavelle has some helpful outlines that covers what things are needed for the test.
- Sun Nov 18, 2018 9:43 pm
- Forum: General Science Questions
- Topic: Thanksgiving Week
- Replies: 8
- Views: 893
Re: Thanksgiving Week
No lecture on Wednesday, Thursday, or Friday.
- Sun Nov 18, 2018 9:42 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Resonance Structures and bond angles
- Replies: 4
- Views: 2218
Re: Resonance Structures and bond angles
For the bond length part of the question, the bond length does not affect the shape since the electron cloud is evenly distributed throughout the resonance structure so that there is an even length between the bonds that are in resonance.
- Sun Nov 18, 2018 9:41 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Lone pairs
- Replies: 5
- Views: 525
Re: Lone pairs
Yes. A lone pair adds one more electron cloud to the shape which changes the shape (and in turn the name) as well as the bond angles.
- Wed Nov 14, 2018 12:04 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Determining VSEPR bond angles
- Replies: 5
- Views: 1827
Re: Determining VSEPR bond angles
Will we be tested on bond angles at all? If so, is there a set amount of angles that we should memorize?
- Wed Nov 14, 2018 12:03 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Octet Rule
- Replies: 6
- Views: 747
Re: Octet Rule
Elements in the third period can utilize the d oribital, thus allowing it to have more than an octet. However, you do not want to not have at least an octet with all your elements (with the exceptions being H, He, Li, and Be).
- Wed Nov 14, 2018 11:59 am
- Forum: Administrative Questions and Class Announcements
- Topic: Thanksgiving week
- Replies: 10
- Views: 1281
Re: Thanksgiving week
He said he wants to cancel class on Wednesday but only if we can get through enough content. He has not stated his decision yet.
- Sun Nov 04, 2018 1:06 pm
- Forum: Empirical & Molecular Formulas
- Topic: garlic bread midterm practice #2
- Replies: 5
- Views: 595
Re: garlic bread midterm practice #2
Most likely the error is from a rounding thing from somewhere in your calculations considering the number you are multiplying by is big yet the amount of error is pretty minor.
- Sat Nov 03, 2018 11:30 pm
- Forum: Ionic & Covalent Bonds
- Topic: Chem Midterm
- Replies: 13
- Views: 1093
Re: Chem Midterm
8 parts but Lavelle said that there would be a homework question on the test.
- Sat Nov 03, 2018 10:45 pm
- Forum: Administrative Questions and Class Announcements
- Topic: MIDTERM PRACTICE - Garlic Bread Review Session [ENDORSED]
- Replies: 121
- Views: 17222
- Sat Oct 27, 2018 8:12 pm
- Forum: Lewis Structures
- Topic: Lewis Dot Structures
- Replies: 3
- Views: 425
Re: Lewis Dot Structures
The bonds are usually dependent on the amount of electrons two atoms share. Thus, bonds will be a double bond when four electrons are shared between two atoms and a bond will be a single bond when two electrons are shared between atoms.
- Sat Oct 27, 2018 8:09 pm
- Forum: Ionic & Covalent Bonds
- Topic: Electron Affinity vs. Ionization Energy [ENDORSED]
- Replies: 4
- Views: 454
Electron Affinity vs. Ionization Energy [ENDORSED]
Is electron affinity and ionization directly related or are they the same thing? If they are related, is there any equation which relates the two?
- Sat Oct 27, 2018 8:06 pm
- Forum: Heisenberg Indeterminacy (Uncertainty) Equation
- Topic: Indeterminacy Question
- Replies: 2
- Views: 1382
Indeterminacy Question
If I have an indeterminacy of delta x, does that mean that any x that I get will be in the range +- delta x or +- delta x/2?
- Sun Oct 21, 2018 5:49 pm
- Forum: Properties of Electrons
- Topic: Test question
- Replies: 6
- Views: 598
Re: Test question
I don't think we need to know anything that wasn't covered in lecture.
- Sun Oct 21, 2018 5:46 pm
- Forum: Quantum Numbers and The H-Atom
- Topic: Principle Quantum #
- Replies: 5
- Views: 687
Re: Principle Quantum #
http://quantumnumbers.weebly.com/uploads/1/2/2/1/12213482/794280614.jpg
The Principal Quantum numbers signify the orbital in which the electron is in and thus the energy level of the electron.
The Principal Quantum numbers signify the orbital in which the electron is in and thus the energy level of the electron.
- Sun Oct 21, 2018 5:43 pm
- Forum: *Shrodinger Equation
- Topic: Use of Schrodinger equation
- Replies: 3
- Views: 441
Re: Use of Schrodinger equation
Lavelle mentioned that the calculations for the Schrodinger Equation was not necessary for the test but the fundamental concepts would be tested.
- Thu Oct 11, 2018 1:54 pm
- Forum: General Science Questions
- Topic: Khan Academy
- Replies: 10
- Views: 1489
Khan Academy
I have been looking for other ways to review. Has anyone tried to study via Khan Academy and if so, has the review with Khan Academy more or less helpful than reviewing lecture notes and the book?
- Thu Oct 11, 2018 1:46 pm
- Forum: Administrative Questions and Class Announcements
- Topic: So can we do problems from Review of Chemistry for week 2 homework?
- Replies: 4
- Views: 279
Re: So can we do problems from Review of Chemistry for week 2 homework?
Some people have already had their TA Discussion section which is why there are already questions about it. I don't think its needed to do the week 2 questions for your week 1 homework, its just that people have already started next week's homework. As far as I understand, any 7 questions that were ...
- Thu Oct 11, 2018 1:43 pm
- Forum: Student Social/Study Group
- Topic: Studying techniques
- Replies: 12
- Views: 803
Re: Studying techniques
I have been doing the last few problems for each section and trying to solve it over and over again until I completely understand it. Its been helping with the conceptual side of chemistry.
- Thu Oct 04, 2018 9:11 pm
- Forum: Empirical & Molecular Formulas
- Topic: Question M.19 (Sixth Edition)
- Replies: 2
- Views: 349
Re: Question M.19 (Sixth Edition)
To start, you have to convert CO2, H2O, and N2 into mols using their molar mass and the grams given to you for each substance (.682g for CO2, .174g for H2O, and .110g for N2). The 194 g.mol^-1 for caffeine isn't important until later when you need to calculate the molecular formula from the empirica...
- Thu Oct 04, 2018 9:04 pm
- Forum: SI Units, Unit Conversions
- Topic: Scientific Notation
- Replies: 11
- Views: 1073
Re: Scientific Notation
I believe that scientific notation is usually used if it is smaller the quantity uses 10^-2 or smaller or 10^2 or bigger.
- Thu Oct 04, 2018 8:56 pm
- Forum: SI Units, Unit Conversions
- Topic: L35 Tons Conversion Rate
- Replies: 4
- Views: 409
L35 Tons Conversion Rate
Sodium bromide, NaBr, which is used to produce AgBr for use in photographic film, can itself be prepared as follows. Fe + Br2 -> FeBr2 FeBr2 + Br2 -> Fe3Br8 Fe3Br8 + Na2CO3 -> NaBr + CO2 + Fe3O4 What mass of iron, in kilograms, is needed to produce 2.50 t of NaBr? Note that these equations must firs...