Search found 43 matches
- Fri Dec 07, 2018 9:36 pm
- Forum: Conjugate Acids & Bases
- Topic: Oxoacids
- Replies: 2
- Views: 549
Oxoacids
Can someone explain to me what an oxoacid is, and how it differs from a normal acid?
- Tue Dec 04, 2018 4:31 pm
- Forum: Electronegativity
- Topic: Trend of Electronegativity
- Replies: 18
- Views: 4136
Re: Trend of Electronegativity
The trends are the same. They increase up a group and across a period. It usually helps me to draw a diagonal line up and across the periodic table to remind myself of this trend during tests!
- Tue Dec 04, 2018 4:29 pm
- Forum: Sigma & Pi Bonds
- Topic: Rotating Bond?
- Replies: 4
- Views: 679
Re: Rotating Bond?
Sigma bonds are allowed to rotate because the electron distribution does not change and bond strength stays the same due to the fact that electron density in sigma bonds are along the axis
- Tue Dec 04, 2018 4:27 pm
- Forum: Naming
- Topic: Naming using Prefixes
- Replies: 1
- Views: 211
Naming using Prefixes
How do you know which prefix to use? Bi vs Bis, Tri vs Tris, Tetra vs Tetrakis
- Fri Nov 30, 2018 2:19 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Coordination Number
- Replies: 10
- Views: 921
Re: Coordination Number
the coordination number is the number of atoms/ions that surround the central atom and you find it by calculating the charge
- Mon Nov 26, 2018 8:21 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: Intermolecular forces and melting/boiling points
- Replies: 4
- Views: 1209
Re: Intermolecular forces and melting/boiling points
Dipole Dipole is molecules having a concentration of charge in a certain area due to polarity, which allows for greater attraction with another molecule that has its charges concentrated in certain areas. Hydrogen bonding is just super strong Dipole Dipole because of the Hydrogen with very electron...
- Mon Nov 26, 2018 6:43 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: Intermolecular forces and melting/boiling points
- Replies: 4
- Views: 1209
Intermolecular forces and melting/boiling points
How does hydrogen bonding, LDF forces, and dipole dipole interactions affect the melting and boiling points of molecules? does it have to do with the electronegativity or strong/weakness of the force?
- Mon Nov 26, 2018 6:41 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: Test 3
- Replies: 2
- Views: 358
Re: Test 3
Yes, these will be on the test
- Sun Nov 25, 2018 7:39 pm
- Forum: Bond Lengths & Energies
- Topic: Isolobal Principle
- Replies: 1
- Views: 442
Isolobal Principle
Can someone explain the isolobal principle/analogy to me? In problem 3.101 of the 6th edition, they replace bonds of C-H in the benzene structure with nitrogen but I'm confused as to why this is possible or why it happens.
- Fri Nov 23, 2018 10:33 pm
- Forum: Dipole Moments
- Topic: Polarity
- Replies: 9
- Views: 928
Re: Polarity
Since oxygen is more electronegative, it pull on the molecule making it polar
- Fri Nov 23, 2018 10:32 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Test 3
- Replies: 10
- Views: 980
Re: Test 3
It covers all of chapter 4 and the end of chapter three as outlined on his website
- Fri Nov 23, 2018 10:30 pm
- Forum: Hybridization
- Topic: reason for hybridization
- Replies: 9
- Views: 10118
Re: reason for hybridization
It exists because hybridized orbitals are lower in energy which results in a more stable compound
- Sun Nov 18, 2018 9:47 pm
- Forum: Quantum Numbers and The H-Atom
- Topic: Degeneracy
- Replies: 8
- Views: 1366
Re: Degeneracy
Degeneracy is basically the levels of orbitals with the same energy, signified by the principle quantum number
- Sun Nov 18, 2018 9:46 pm
- Forum: Resonance Structures
- Topic: Radicals
- Replies: 11
- Views: 1389
Re: Radicals
A radical has an unpaired valence electron on an atom
- Thu Nov 15, 2018 1:59 pm
- Forum: Octet Exceptions
- Topic: The center atom
- Replies: 20
- Views: 3194
Re: The center atom
The central atom is usually the one with the lowest ionization energy
- Thu Nov 15, 2018 1:58 pm
- Forum: Formal Charge and Oxidation Numbers
- Topic: Formal Charge
- Replies: 10
- Views: 1639
Formal Charge
When determining molecular structures, is having the formal charge be 0 or having a complete octet more important?
- Thu Nov 15, 2018 1:56 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Trigonal Shapes
- Replies: 4
- Views: 585
Trigonal Shapes
What is the difference between trigonal planar and trigonal pyramidal? why are the bond angles in trigonal planar 120 degrees but the angles in trigonal pyramidal differ?
- Mon Nov 12, 2018 8:50 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Molecules with Lone Pairs
- Replies: 1
- Views: 257
Molecules with Lone Pairs
For problem 4.1 in the 6th edition, it asks whether there can be lone pairs on the central atom of the ball and stick models of the atom. part (a) models three atoms with an angle of 120 degrees and the second is a linear model with an angle of 180 degrees. how does the degree decide how many lone p...
- Fri Nov 09, 2018 12:47 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Tetrahedral molecules
- Replies: 4
- Views: 400
Re: Tetrahedral molecules
Yes, the way he spoke about it in lecture today was that since it is 3d, the tetrahedral molecules have bond angles of 109.5 degrees
- Fri Nov 09, 2018 12:46 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Different Shapes
- Replies: 4
- Views: 356
Re: Different Shapes
In today's lecture (11/9) we went over linear, trigonal planar, and tetrahedral.
- Fri Nov 09, 2018 12:45 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Trigonal Planar
- Replies: 8
- Views: 923
Re: Trigonal Planar
It would be 3d
- Sun Nov 04, 2018 4:44 pm
- Forum: Lewis Structures
- Topic: Problem 3.57 6th edition
- Replies: 1
- Views: 140
Problem 3.57 6th edition
This asks to draw the lewis and appropiate resonance structures for a hydrogen sulfite ion. Why does the hydrogen bond to one of the oxygens, instead of just attaching to the sulfer?
- Sun Nov 04, 2018 4:33 pm
- Forum: Lewis Structures
- Topic: Expanded Octets
- Replies: 2
- Views: 319
Expanded Octets
Why can some elements have expanded octects? for example, problem 3.57 in the 6th edition asks for lewis structure of a sulfite ion (SO3)2- and in the expanded octet, sulfur has 10 electrons attached to it. why can this happen and when do i know that a compound has an expanded octet?
- Sun Nov 04, 2018 4:10 pm
- Forum: Empirical & Molecular Formulas
- Topic: Empirical Formulas with Masses
- Replies: 3
- Views: 417
Re: Empirical Formulas with Masses
You would first need to find the mass percentage of the element, and then assume that the mass percent is equal to grams and that you have 100 g of the substance.
- Sun Nov 04, 2018 4:08 pm
- Forum: Trends in The Periodic Table
- Topic: Ionization Energies
- Replies: 2
- Views: 259
Ionization Energies
Do we need to know how to calculate the exact ionization energies for the midterm? If so, how do we do it?
- Sun Nov 04, 2018 4:07 pm
- Forum: Formal Charge and Oxidation Numbers
- Topic: Formal Charge
- Replies: 7
- Views: 948
Formal Charge
Should the formal charge for a Lewis structure ever not be equal to zero? Is something for sure wrong with the structure if the formal charge not equal to zero?
- Sat Nov 03, 2018 9:07 am
- Forum: Lewis Structures
- Topic: Do brackets go over cations or anions or either or both?
- Replies: 3
- Views: 563
Re: Do brackets go over cations or anions or either or both?
I believe you put them on both the cation and anion to show how they are charged. []- and []+
- Mon Oct 29, 2018 12:26 pm
- Forum: Lewis Structures
- Topic: 3.33 Lewis Structure for NOF
- Replies: 1
- Views: 942
3.33 Lewis Structure for NOF
in problem 33 in the 6th edition, it asks for the lewis structure of NOF. the solutions manual shows a double bond between O and N, with N having a lone pair, O having 2 lone pairs, and F having 3 lone pairs and a bond with N. Why couldn't you have two double bonds between N and O/F with O and F hav...
- Sun Oct 28, 2018 4:00 pm
- Forum: Trends in The Periodic Table
- Topic: Atomic Radius
- Replies: 8
- Views: 754
Re: Atomic Radius
I doubt we will be expected to know exact values. I think just knowing the trends and which radii is larger is sufficient
- Sun Oct 28, 2018 3:53 pm
- Forum: Administrative Questions and Class Announcements
- Topic: MIDTERM PRACTICE - Garlic Bread Review Session [ENDORSED]
- Replies: 121
- Views: 17352
- Wed Oct 24, 2018 11:46 am
- Forum: Trends in The Periodic Table
- Topic: Test 2
- Replies: 3
- Views: 310
Re: Test 2
test 2 only covers material up to last friday's lecture, so it includes nothing about periodic table trends
- Tue Oct 23, 2018 1:06 am
- Forum: Properties of Light
- Topic: Test 2 Outline 2 Question About Electron Transition
- Replies: 1
- Views: 195
Re: Test 2 Outline 2 Question About Electron Transition
Basically electrons in both atoms and molecules can be excited to higher energy states (n=1,2 etc) so when they emit electromagnetic radiation, it gives detail to the spectroscopy
- Sun Oct 21, 2018 7:17 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: test #2
- Replies: 4
- Views: 347
Re: test #2
My TA mentioned that it would 40 points. It is going to be less questions apparently, but more in depth
- Fri Oct 19, 2018 8:53 am
- Forum: Einstein Equation
- Topic: Numbers to memorize [ENDORSED]
- Replies: 37
- Views: 4053
Re: Numbers to memorize [ENDORSED]
Our first test had a formula sheet on the front. I assume that is the same sheet we will be given all quarter
- Thu Oct 18, 2018 11:47 am
- Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
- Topic: Balmer and Lyman Series
- Replies: 2
- Views: 211
Balmer and Lyman Series
Can someone explain what the Balmer and Lyman series are? I know that the Lyman series corresponds to UV light and the Balmer series corresponds to visible light, but where is this relevant and what does this mean?
- Sun Oct 14, 2018 8:06 pm
- Forum: Properties of Light
- Topic: C=Wavelength*Frequency
- Replies: 11
- Views: 3152
Re: C=Wavelength*Frequency
C represents the speed of light
- Sun Oct 14, 2018 8:05 pm
- Forum: Properties of Light
- Topic: Chapters 1 and 2 logisitcs
- Replies: 3
- Views: 254
Re: Chapters 1 and 2 logisitcs
Homework due this week is chapter's 1 and 2 I believe. We definitely have not started a new chapter since Friday, so homework should be from 2 especially, and 1 if you need practice. Every TA is different, but if you are doing current material, they should not mind.
- Mon Oct 08, 2018 7:07 pm
- Forum: Empirical & Molecular Formulas
- Topic: Mass Percent Composition
- Replies: 7
- Views: 1100
Re: Mass Percent Composition
These problems should always add up to 100%. If not, it might be a trick question or you are mis calculating.
- Sun Oct 07, 2018 4:10 pm
- Forum: SI Units, Unit Conversions
- Topic: Formula Sheet?
- Replies: 6
- Views: 568
Re: Formula Sheet?
There is a formula sheet uploaded onto Lavelle's website, however, it doesn't have much to help with the fundamentals section. He will probably still give it to us, but not sure how useful it will be. The only thing to memorize for this test would probably be the SI unit conversions.
- Thu Oct 04, 2018 4:27 pm
- Forum: SI Units, Unit Conversions
- Topic: Homework Questions [ENDORSED]
- Replies: 14
- Views: 1190
Re: Homework Questions [ENDORSED]
Will homework always be due on Friday during the lecture? Or will we switch to turning in HW to the TA during our discussion period? Just wondering because what if we have to turn in homework that wasn't covered yet (in case our lecture is after our discussion period). Homework will be due, startin...
- Thu Oct 04, 2018 4:14 pm
- Forum: Balancing Chemical Reactions
- Topic: H.11 part 2 balancing tricks?
- Replies: 2
- Views: 245
Re: H.11 part 2 balancing tricks?
I think that balancing by jumping back and forth is the best way to do it. I always like to leave oxygen last because sometimes things get weird with the oxygen (and theres usually a lot of oxygen in complicated equations), but other than that, I can't think of any good 'tricks'
- Thu Oct 04, 2018 1:26 pm
- Forum: Accuracy, Precision, Mole, Other Definitions
- Topic: Molecules vs Formula Units? E21
- Replies: 2
- Views: 199
Molecules vs Formula Units? E21
In the 6th Edition, questions E21 asks for the amount (in moles) of molecules and formula units. What is the difference between these when calculating?
- Wed Oct 03, 2018 11:51 am
- Forum: Accuracy, Precision, Mole, Other Definitions
- Topic: Question E1(6th Edition)
- Replies: 7
- Views: 697
Re: Question E1(6th Edition)
I began this problem by multiplying 1.00 mol of Ag by Avogadro's number to get 6.022x10^23 atoms of Ag. Then I multiplied that by 2(144 pm)--144 pm is the radius of the atom, so to get the total length of the atom you have to double it. The end result was 1.73x10^26 pm, which is equal to 1.73x10^11...