Search found 55 matches

by claribel charway 1I
Sat Dec 07, 2019 8:15 pm
Forum: Resonance Structures
Topic: when there is resonance
Replies: 5
Views: 164

Re: when there is resonance

No, you need at least 3 atoms to have resonance because the double bond must be switched with one that has a single bond.
by claribel charway 1I
Sat Dec 07, 2019 7:39 pm
Forum: Student Social/Study Group
Topic: Grades
Replies: 14
Views: 405

Re: Grades

I am a bit confused by the grading but it sounds like the whole class is rounding comparative to everyone else's total score out of 500.
by claribel charway 1I
Sat Dec 07, 2019 7:37 pm
Forum: Lewis Structures
Topic: Lewis for carbon monoxide
Replies: 3
Views: 228

Re: Lewis for carbon monoxide

With a double bond and one lone pair on each atom, you do not form a full octet because there's only 6 electrons on carbon and oxygen. In order to get full octets and an overall neutral charge you must use the triple bond and a lone pair on each.
by claribel charway 1I
Thu Dec 05, 2019 4:09 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Shape of Coordination Compounds
Replies: 1
Views: 41

Shape of Coordination Compounds

How many coordination compound shapes do we need to know?
by claribel charway 1I
Thu Dec 05, 2019 2:51 pm
Forum: Naming
Topic: naming
Replies: 5
Views: 69

Re: naming

I am not sure exactly how much naming will be on the final but definitely memorize the worksheet he gave us.
by claribel charway 1I
Thu Dec 05, 2019 2:50 pm
Forum: Biological Examples
Topic: Biological questions on the final
Replies: 5
Views: 132

Re: Biological questions on the final

I think all you need to know is hemoglobin, myoglobin and cisplatin.
by claribel charway 1I
Sat Nov 30, 2019 5:05 pm
Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
Topic: Drawing sigma & Pi bonds
Replies: 7
Views: 194

Re: Drawing sigma & Pi bonds

the most important thing is knowing where sigma and pi bonds are located and their orientation; sigma bonds are end to end while pi bonds are side by side
by claribel charway 1I
Fri Nov 29, 2019 5:50 pm
Forum: Administrative Questions and Class Announcements
Topic: Studying for the Final [ENDORSED]
Replies: 11
Views: 265

Re: Studying for the Final [ENDORSED]

Personally, I like videos. I would also focus on the major concepts in addition to just doing problems.
by claribel charway 1I
Fri Nov 29, 2019 3:43 pm
Forum: Student Social/Study Group
Topic: Final Review Sessions
Replies: 7
Views: 196

Re: Final Review Sessions

He doesn't have anything up yet on the website about review sessions but I'm sure he'll mention it on Monday. There's also the workshops and step up sessions for review.
by claribel charway 1I
Fri Nov 29, 2019 3:40 pm
Forum: Calculating the pH of Salt Solutions
Topic: pH vs. pOH
Replies: 17
Views: 325

Re: pH vs. pOH

pH is a measure of acidity, specifically it measures the H+ ions. pOH is a measure of basicity, specifically the OH ions. Their respective values are inverse of each other. For example, ph of 0 is a pOH of 14.
by claribel charway 1I
Fri Nov 29, 2019 3:36 pm
Forum: Student Social/Study Group
Topic: Preparing for the final
Replies: 25
Views: 337

Re: Preparing for the final

The same thing happened to me as well. I think the best thing to do is to do textbook problems but also attend as many review sessions as possible. From what I heard, the final might be more conceptually focused so understanding certain principles is imperative.
by claribel charway 1I
Sun Nov 24, 2019 12:49 pm
Forum: Student Social/Study Group
Topic: Final Jitters
Replies: 127
Views: 33483

Re: Final Jitters

I get test anxiety as well. I recommend not studying at all the day of the final. As terrifying as it sounds it will help you heeled when it comes time for the test. Your brain won’t be overloaded with chem info and it personally helps me feel confident. I try to listen to the same music that I stud...
by claribel charway 1I
Sun Nov 24, 2019 12:43 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Lone pairs
Replies: 13
Views: 147

Re: Lone pairs

the only lone pairs that matter are the ones on the central atom, for example it makes the difference between linear and bent
by claribel charway 1I
Sun Nov 24, 2019 12:41 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: AXE Format
Replies: 34
Views: 274

Re: AXE Format

Writing just E is fine.
by claribel charway 1I
Sun Nov 24, 2019 12:38 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Non-polar molecules with different non-central atoms
Replies: 3
Views: 40

Re: Non-polar molecules with different non-central atoms

It depends where the two atoms are placed. If they same atoms aren’t opposite of each other their dipole moments won’t cancel out thereby making it polar.
by claribel charway 1I
Wed Nov 20, 2019 8:14 am
Forum: Determining Molecular Shape (VSEPR)
Topic: 2E.13 part a
Replies: 3
Views: 46

2E.13 part a

For part A in question 13 of 2E, I3- has a bond angle of 180 degrees even though it has 3 lone pairs on it. Why isn't its bond angle less than 180 degrees?
by claribel charway 1I
Sun Nov 17, 2019 11:36 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Bonds in VSEPR
Replies: 11
Views: 106

Re: Bonds in VSEPR

Double and Triple bonds are accounted for as single bonds. So regardless of the number of bonds, it only counts as one region of electron density.
by claribel charway 1I
Sun Nov 17, 2019 11:31 pm
Forum: Ionic & Covalent Bonds
Topic: Study Group
Replies: 8
Views: 131

Re: Study Group

I would love to join! I really need to study before this test.
by claribel charway 1I
Sun Nov 17, 2019 11:30 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Repulsion Strength
Replies: 5
Views: 98

Re: Repulsion Strength

Lone pairs have the greatest repulsion because they are closer together. Lone bonding is the next strongest because it is the next closest. Bonding-bonding pairs are the weakest because the electrons are more spread apart since each atom takes an electron within its cloud.
by claribel charway 1I
Sun Nov 17, 2019 11:19 pm
Forum: Coordinate Covalent Bonds
Topic: coordinate covalent bond
Replies: 9
Views: 231

Re: coordinate covalent bond

What is the difference or what distinguishes a coordinate covalent bond from a regular bond? In a coordinate covalent bond both electrons come from the same atom while in a regular bond each atom provides an electron. Oh, got it! The only way you would know the type of bond (coordinate covalent vs ...
by claribel charway 1I
Sun Nov 17, 2019 11:14 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Effect of electronegativity difference on bond angles
Replies: 3
Views: 49

Re: Effect of electronegativity difference on bond angles

Yes, the more electronegative fluorine atom pulls more of the electron cloud decreasing the repulsion between the C-H bond. But I think it increases the F-C-H bond angle because the fluorine is pulled out "further" so the H-C-H bond angle will decrease as a result of the pull. For the test...
by claribel charway 1I
Fri Nov 15, 2019 9:55 am
Forum: Interionic and Intermolecular Forces (Ion-Ion, Ion-Dipole, Dipole-Dipole, Dipole-Induced Dipole, Dispersion/Induced Dipole-Induced Dipole/London Forces, Hydrogen Bonding)
Topic: 3F problem 3
Replies: 3
Views: 63

Re: 3F problem 3

Dipole-dipole moments will exist for b,c, and d. CH4 and CCl4 are completely uniform since the atoms around the central atom are the same. Because of this there is not dipole pull because there’s an even amount of electronegativity around carbon. In the case of CH3Cl, CH2Cl2, and CHCl3 there’s diffe...
by claribel charway 1I
Fri Nov 15, 2019 9:51 am
Forum: General Science Questions
Topic: Test 2
Replies: 4
Views: 81

Re: Test 2

Everything from 2D on so chemical forces/bonds and structures (Lewis and vsepr)so basically from the midterm to the lecture today
by claribel charway 1I
Wed Nov 13, 2019 8:41 pm
Forum: Coordinate Covalent Bonds
Topic: coordinate covalent bond
Replies: 9
Views: 231

Re: coordinate covalent bond

Ruby Richter 4G wrote:What is the difference or what distinguishes a coordinate covalent bond from a regular bond?

In a coordinate covalent bond both electrons come from the same atom while in a regular bond each atom provides an electron.
by claribel charway 1I
Wed Nov 13, 2019 8:33 pm
Forum: Coordinate Covalent Bonds
Topic: coordinate covalent bond
Replies: 9
Views: 231

Re: coordinate covalent bond

Water is an example of a coordinate covalent bond, oxygen provides both electrons to the hydrogens.
by claribel charway 1I
Sat Nov 09, 2019 6:57 pm
Forum: Electronegativity
Topic: Polar Molecules
Replies: 4
Views: 73

Re: Polar Molecules

If the electronegativity difference is greater than 2 then it is polar. It could be either ionic polar or covalent polar.
by claribel charway 1I
Sat Nov 09, 2019 6:55 pm
Forum: Dipole Moments
Topic: calculating dipole moments
Replies: 1
Views: 27

Re: calculating dipole moments

Dipole moments are calculated by multiplying the charge by the distance between the atoms.
by claribel charway 1I
Sat Nov 09, 2019 6:52 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: Hydrogen Bonding
Replies: 3
Views: 33

Re: Hydrogen Bonding

It bonds to highly electronegative elements while being not as negative. As a result, there is an attraction between a very weak element and a very strong one that tremendously pulls on hydrogen’s electron. Hydrogen can be considered the weakest element because it only had one electron to exert forc...
by claribel charway 1I
Sat Nov 02, 2019 4:58 pm
Forum: Lewis Structures
Topic: Resonance Hybrids
Replies: 3
Views: 48

Re: Resonance Hybrids

Resonance structures are the different variations of the double bond. A resonance hybrid is the blend of all three resonance structures. It is how the molecules are represented in real life because it evenly distributes the double bond. This is known as the delocalization of electrons.
by claribel charway 1I
Sat Nov 02, 2019 4:55 pm
Forum: Ionic & Covalent Bonds
Topic: "Primarily Ionic" Bonds (HW 2D.3)
Replies: 2
Views: 53

Re: "Primarily Ionic" Bonds (HW 2D.3)

There is still an electronegative difference between Be and Br but it isn't as great as the one between Ba and Br. I believe that's why you would regard BaBr2 as primarily ionic
by claribel charway 1I
Sat Nov 02, 2019 4:45 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: What d to include when "counting valence electrons including d electrons"
Replies: 1
Views: 44

Re: What d to include when "counting valence electrons including d electrons"

Yes, Sb's 4d orbital was full and would then not be considered as valence electrons
by claribel charway 1I
Sat Nov 02, 2019 4:43 pm
Forum: Octet Exceptions
Topic: Octet Exceptions
Replies: 3
Views: 59

Re: Octet Exceptions

It has to be from period 3 onward
by claribel charway 1I
Sat Nov 02, 2019 4:42 pm
Forum: Lewis Structures
Topic: drawing lewis structures
Replies: 5
Views: 77

Re: drawing lewis structures

Br has an expanded octet
by claribel charway 1I
Sun Oct 27, 2019 1:21 am
Forum: Properties of Light
Topic: Light vs. Particles
Replies: 2
Views: 61

Re: Light vs. Particles

Particles use de Broglie's equation (lambda=h/mv) because they have mass. Light uses E=hc/lambda because the equation features the speed of light and does not include mass since light does not have measurable mass.
by claribel charway 1I
Sun Oct 27, 2019 1:16 am
Forum: SI Units, Unit Conversions
Topic: Midterm
Replies: 6
Views: 214

Re: Midterm

I believe it will have everything up to chemical bonds on there.
by claribel charway 1I
Sun Oct 27, 2019 1:14 am
Forum: Einstein Equation
Topic: Total Energy of Light
Replies: 2
Views: 144

Re: Total Energy of Light

technically E=hf=hc/lambda calculates total energy of a photon
by claribel charway 1I
Sun Oct 27, 2019 1:11 am
Forum: Resonance Structures
Topic: Resonance
Replies: 4
Views: 68

Re: Resonance

A substance has resonance when the molecule requires a double bond that can be shifted to another single bond. As long as there's at least three elements and a required double bond, a resonance structure can be made.
by claribel charway 1I
Thu Oct 24, 2019 9:12 am
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Order of electron configuration
Replies: 6
Views: 72

Re: Order of electron configuration

Although 4s is filled first, you write 3D first because it still occupies a slighter lower energy level.
by claribel charway 1I
Sat Oct 19, 2019 5:51 pm
Forum: General Science Questions
Topic: Tutoring
Replies: 6
Views: 148

Re: Tutoring

The tutoring offered on the website are all group sessions. Maybe you could contact your TA for one-on-one sessions but I would say that showing up to their office hours works best because you can ask them all the questions you have.
by claribel charway 1I
Sat Oct 19, 2019 5:46 pm
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: Determining # of Subshells in an Orbital
Replies: 3
Views: 55

Re: Determining # of Subshells in an Orbital

As far as I know it is just something you memorize.
by claribel charway 1I
Mon Oct 14, 2019 3:57 pm
Forum: Heisenberg Indeterminacy (Uncertainty) Equation
Topic: Indeterminacy Equation
Replies: 3
Views: 59

Re: Indeterminacy Equation

The uncertainty is the range that the velocity would fall into. So in this case, it would fall between 0 and 10 m/s.
by claribel charway 1I
Mon Oct 14, 2019 3:55 pm
Forum: *Shrodinger Equation
Topic: Midterm
Replies: 14
Views: 447

Re: Midterm

The midterm is November 6.
by claribel charway 1I
Wed Oct 09, 2019 8:25 am
Forum: Photoelectric Effect
Topic: Photon [ENDORSED]
Replies: 6
Views: 126

Re: Photon [ENDORSED]

Photons are essentially packets of energy. The photoelectric effect basically states that a certain amount of energy is required to emit an electron from a metal (work function). If the photon's energy equals or exceeds the work function then the photon will transfer it's energy to the electron so t...
by claribel charway 1I
Wed Oct 09, 2019 8:19 am
Forum: SI Units, Unit Conversions
Topic: How to express answers
Replies: 13
Views: 271

Re: How to express answers

He hasn't said how he wants them expressed. I would go with scientific notation with the base units (g, mole, L). Just always make sure your sig figs are correct.
by claribel charway 1I
Wed Oct 09, 2019 8:12 am
Forum: Significant Figures
Topic: Are we allowed to round when showing work?
Replies: 7
Views: 125

Re: Are we allowed to round when showing work?

I believe so. I usually do the same thing but on the test I'm going to show all my unrounded answers just in case. The most important thing is that you're not rounding before the final answer.
by claribel charway 1I
Wed Oct 09, 2019 8:11 am
Forum: SI Units, Unit Conversions
Topic: Conversion
Replies: 3
Views: 97

Re: Conversion

Yes millimol means 10^-3 moles. When converting from moles to grams you multiply the moles by the molar mass.
Moles * grams/mole = grams
by claribel charway 1I
Wed Oct 02, 2019 7:21 pm
Forum: Molarity, Solutions, Dilutions
Topic: Dilution Calculations
Replies: 3
Views: 77

Re: G.23

I believe it's just extra information that isn't necessary to finding the solution to the problem.
by claribel charway 1I
Wed Oct 02, 2019 7:17 pm
Forum: Limiting Reactant Calculations
Topic: Limiting reactant
Replies: 4
Views: 34

Re: Limiting reactant

When you compare the moles of the reactants check to see which compound is in excess. For example is A:B is 1:2 in the balanced equation. If the moles calculated for A is 1 and the moles calculated for B is 3 then B is in excess meaning that A is the limiting reactant. A doesn't have enough of itsel...
by claribel charway 1I
Wed Oct 02, 2019 7:11 pm
Forum: Empirical & Molecular Formulas
Topic: Homework question M.17
Replies: 2
Views: 104

Re: Homework question M.17

The 1.0 comes form the hydrogen in HA and the 17.0 comes from the OH (16 g + 1 g) in XOH.
by claribel charway 1I
Wed Oct 02, 2019 7:07 pm
Forum: SI Units, Unit Conversions
Topic: Homework 2
Replies: 7
Views: 107

Re: Homework 2

I'm not 100% sure but believe it would be the first discussion of next week since Week 2 homework needs to be turned in during week 2.
by claribel charway 1I
Wed Oct 02, 2019 7:04 pm
Forum: Molarity, Solutions, Dilutions
Topic: Molarity
Replies: 4
Views: 48

Re: Molarity

First you need to subtract the mass of (OH)x2 from the molar mass of the metal. When subtracting you find out the unknown metal is calcium. 74.10 - 34.02 = 40.08 Next, add the mass of Sulfur to the remaining amount. This is adding the masses of Calcium and Sulfur to create calcium sulfide. 40.08 + 3...
by claribel charway 1I
Wed Oct 02, 2019 6:58 pm
Forum: Empirical & Molecular Formulas
Topic: H25 Fundamental Question
Replies: 3
Views: 117

Re: H25 Fundamental Question

Phosphorus has 5 valence electrons. The numbers in parenthesis refer to the oxidation states. Phosphorus V is when the element is in the +5 oxidation state meaning that it has removed all its valence electrons. Phosphorus iii means 2 electrons have been removed leaving a +3 charge.
by claribel charway 1I
Wed Oct 02, 2019 6:42 pm
Forum: Molarity, Solutions, Dilutions
Topic: Molarity
Replies: 9
Views: 148

Re: Molarity

Knowing the molarity can also help you find the moles of a compound given that you know the volume and vice versa.

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