## Search found 66 matches

Sat Jan 16, 2021 8:24 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: Temperature
Replies: 12
Views: 51

### Re: Temperature

If this was to happen, the value of K would also be changed due to the temperature change. Additionally, this would require extra information such as finding two values of Q that are different.
Sat Jan 16, 2021 8:21 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Kw constant
Replies: 25
Views: 50

### Re: Kw constant

[H2O] will be left out due to the large excess which is why it can be disregarded due to its presence in both the reactant and products as stated in the lecture.
Sat Jan 16, 2021 8:18 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: When x is negligible in Equilibrium constant
Replies: 34
Views: 93

### Re: When x is negligible in Equilibrium constant

Based on some of the UA's, an equilibrium constant smaller than 10^-4 would allow you to disregard the x for an approximation.
Sat Jan 16, 2021 5:03 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: ka vs kb
Replies: 20
Views: 55

### Re: ka vs kb

I believe that the a and b are simply to label and distinguish acid and bases. Ka representing the dissociation of acid while Kb deals with base which provides the Kw value.
Sat Jan 16, 2021 4:53 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Le Chatelier's with Solids
Replies: 5
Views: 17

### Re: Le Chatelier's with Solids

Solid and liquids are omitted due to the fact that they do not have concentrations. Therefore, they would have no influence on the K and will not favor reactants or products.
Sun Jan 10, 2021 9:42 am
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Response of Equilibria to Change
Replies: 8
Views: 23

### Re: Response of Equilibria to Change

K, the equilibrium constant can only be affected if the temperature is altered. Other factors do not affect this as discussed in the previous lecture that the constant will still be the same due to the ratio. Changing factors like pressure will simply change when equilibrium is reached.
Sun Jan 10, 2021 9:39 am
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: Q and K
Replies: 38
Views: 118

### Re: Q and K

Q and K are found using the same concept of Product/Reactants. The main difference between the two is that the reaction quotient (Q) is identified when the reaction is not at equilibrium while K is the actual equilibrium constant. Comparing these two will provide us information if the reactant or pr...
Sun Jan 10, 2021 9:32 am
Forum: Equilibrium Constants & Calculating Concentrations
Topic: K vs. Q
Replies: 53
Views: 157

### Re: K vs. Q

Correct. Product divided by reactants will determine the K. If reaction is not at equilibrium, Q can be determined in order to identify if the reactant or products will be favored.
Sun Jan 10, 2021 9:29 am
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Changing K
Replies: 3
Views: 20

### Re: Changing K

Right. Temperature is the only factor that could change the K due to its affect during the chemical reaction.
Sun Jan 10, 2021 9:27 am
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Q and K
Replies: 13
Views: 31

### Re: Q and K

Yes, we often use Q in order to determine if the reactant or product will be favored.
Sun Dec 06, 2020 10:12 am
Forum: Lewis Acids & Bases
Topic: Lewis Acids & Bases
Replies: 12
Views: 88

### Re: Lewis Acids & Bases

To add on I have always approached acids and bases by creating my theory that lewis acids are electron deprived and bases are electron rich that can donate to these acids.
Sun Dec 06, 2020 10:00 am
Forum: Lewis Acids & Bases
Topic: Determining Lewis Acids and Bases
Replies: 9
Views: 47

### Re: Determining Lewis Acids and Bases

Lewis acids are often electron acceptors because they need the electron from lone pairs to satisfy the valence electrons that they need. From how I see it, lewis base are those who can afford donating or sharing the lone pairs around the orbitals that they have.
Sun Dec 06, 2020 9:42 am
Forum: Lewis Acids & Bases
Topic: Classification of Lewis Acids and Bases
Replies: 5
Views: 42

### Re: Classification of Lewis Acids and Bases

The way I understood it is to understand that Lewis Acids need the electron that makes them the acceptor because their orbitals or “cloud” is empty. The Lewis Bases have electrons in their cloud that they are able to donate once there is bond that is made.
Sun Dec 06, 2020 9:30 am
Forum: Lewis Acids & Bases
Topic: Bronsted vs. Lewis bases
Replies: 11
Views: 70

### Re: Bronsted vs. Lewis bases

From what I recall that I got from the lecture, both of these have similarly concepts, only that Bronsteds are associated with the protons acceptor while the Lewis bases are associated with the electron donations. I believe he said that they are both similar principles so in regards of defining, we ...
Sun Dec 06, 2020 9:26 am
Forum: Lewis Acids & Bases
Topic: Water
Replies: 62
Views: 480

### Re: Water

Water is able to act both as an acid or a base.
Sun Nov 29, 2020 11:20 am
Forum: Determining Molecular Shape (VSEPR)
Topic: Bond Angles
Replies: 11
Views: 64

### Re: Bond Angles

Lone pairs influence the bond angles by making them decrease because of the repulsion that it causes. In regards of knowing the actual bond angle, we do not need to know the exact angle, only the general idea of how it is influenced.
Sun Nov 29, 2020 11:15 am
Forum: Determining Molecular Shape (VSEPR)
Topic: Determining Bond Angles
Replies: 9
Views: 47

### Re: Determining Bond Angles

Analyzing the shape will help provide a clear understanding of what the bond angles could possibly be. Directly answering your question, yes, a linear molecular shape has a bond angle of 180 degrees.
Sun Nov 29, 2020 11:11 am
Forum: Determining Molecular Shape (VSEPR)
Topic: Bond Angles
Replies: 5
Views: 44

### Re: Bond Angles

I think memorizing that the lone pairs and bond pairs influence the bond angles of the molecular shape/geometry. The way I memorize it is that when a lone pair present, the repulsion has a larger effect causing the bond pairs to be pushed more closely together.
Sun Nov 29, 2020 11:04 am
Forum: Determining Molecular Shape (VSEPR)
Topic: VSEPR Chart
Replies: 18
Views: 104

### Re: VSEPR Chart

Emphasizing what the others have said, it is probably better to just memorize it. The resources that is provided by the TA’s and UA’s will probably be our best bet in regards of being familiar with the shapes, bond angles, etc.
Sun Nov 29, 2020 11:02 am
Forum: Hybridization
Topic: hybridization
Replies: 5
Views: 60

### Re: hybridization

I am unsure but I do not recall the d orbitals being discussed or taught during his lecture, but the s and p orbitals will be on the final exam.
Sun Nov 22, 2020 5:51 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Sapling Week 7-8 #1
Replies: 8
Views: 27

### Re: Sapling Week 7-8 #1

It would be a trigonal pyramid due to information given of the three oxygen bonded with the sulfur along with one lone pair.
Sun Nov 22, 2020 5:42 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Sapling question
Replies: 4
Views: 27

### Re: Sapling question

The angles are experimentally determined and can not be calculated precisely. In this case, the VSEPR will help us the most in determining which angles are larger or smaller based on the bonds that are provided for us to idenitfy.
Sun Nov 22, 2020 5:40 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Bond Angles
Replies: 21
Views: 101

### Re: Bond Angles

From the knowledge I have gained so far, I believe bond angles are determined experimentally. Bond angles change based on the electron repulsion on the different bonds that are given to us.
Sun Nov 22, 2020 5:33 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: different shapes given in notes
Replies: 4
Views: 35

### Re: different shapes given in notes

It is probably essential that we know all of the shapes that was discussed during the lecture. Just to be safe, I think it will be better if we familiarize ourselves beyond what we need to know to prepare us for organic chemistry.
Sun Nov 22, 2020 5:28 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Memorizing Shape Names
Replies: 12
Views: 63

### Re: Memorizing Shape Names

Personally, the only way that it has been helping me is to hop on quizlet and memorize from there.
Sun Nov 15, 2020 1:45 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Writing Electron Configurations
Replies: 9
Views: 76

### Re: Writing Electron Configurations

I think it was written this way because the orbitals that are found in 5s are the outermost shell which means that it easier to take away electrons rather than the 4d shell which it is closer to the nucleus.
Sun Nov 15, 2020 1:39 pm
Forum: Ionic & Covalent Bonds
Topic: Electronegativity difference
Replies: 12
Views: 87

### Re: Electronegativity difference

From my knowledge, the electronegativity is determined experimentally which means that we would be provided values and a table to identify what the question is asking for. Also, even if we do not need find it experimentally, the trends in the periodic table should provide sufficient information to f...
Sun Nov 15, 2020 1:35 pm
Forum: Ionic & Covalent Bonds
Topic: Electronegativity
Replies: 18
Views: 104

### Re: Electronegativity

Wondering the same thing honestly. I think as long as we are familiar with the trends in the periodic table we should be fine on the midterms and exams. If needed, I think the tables will be provided for us if it is needed in the problem.
Sun Nov 15, 2020 1:29 pm
Forum: Dipole Moments
Topic: Sapling number 17
Replies: 10
Views: 78

### Re: Sapling number 17

In CH4, LDR exists because of the fact that C and H do not have much of a difference in their electronegativity. Adding on, drawing the Lewis structure will help visualize that the hydrogen surrounding the atom in the middle are all similar causing the dipole moments to cancel and not have an effect...
Sun Nov 15, 2020 1:11 pm
Forum: Dipole Moments
Topic: Textbook discrepancy
Replies: 6
Views: 45

### Re: Textbook discrepancy

In the lectures and other sessions, the information they provide has the arrow leaning towards the electronegative atom. I would say to ultimately just follow how the lecture demonstrates it rather than the book. In regards of understanding the concept better, I think just go with your personal pref...
Sun Nov 15, 2020 1:08 pm
Forum: Dipole Moments
Topic: Sapling #19
Replies: 12
Views: 76

### Re: Sapling #19

Had the same issue regarding this problem! I figured it was an error in the problem itself but I said it was dipole-dipole.
Sun Nov 08, 2020 2:53 pm
Forum: Lewis Structures
Topic: Atom in the middle of a lewis structure
Replies: 7
Views: 40

### Re: Atom in the middle of a lewis structure

The atom with the lowest ionization energy goes in the middle of the lewis structure because they are more compatible to accept bonds and electrons with other atoms.
Sun Nov 08, 2020 2:49 pm
Forum: Lewis Structures
Topic: Lone Pairs Question
Replies: 22
Views: 119

### Re: Lone Pairs Question

Lone pairs are essentially electrons that belong to that certain atom that is being described. They are not bonded with any other elements.
Sun Nov 08, 2020 2:46 pm
Forum: Ionic & Covalent Bonds
Topic: Extra Valence Electrons
Replies: 10
Views: 55

### Re: Extra Valence Electrons

The elements that you have listed essentially describes the octet rule exceptions in which they are able to accommodate extra electrons due to the period 3 / or 3d subshell.
Sun Nov 08, 2020 2:23 pm
Forum: Electronegativity
Topic: Electronegativity trend
Replies: 18
Views: 92

### Re: Electronegativity trend

Essentially, the electronegativity trend shows that it increases from left to right and bottom to top in the periodic table.
Sun Nov 08, 2020 2:19 pm
Forum: Electronegativity
Topic: Atom size
Replies: 22
Views: 803

### Re: Atom size

I do not think that the size of an atom is influenced by the electronegativity that it contains, but we do see that it is somewhat the opposite of each other because the periodic table shows a trend that electronegativity gradually increases when going left to right/bottom to top of the table. On th...
Sun Nov 01, 2020 11:05 am
Forum: Octet Exceptions
Topic: Octet Exceptions
Replies: 10
Views: 48

### Re: Octet Exceptions

I think these are exceptions due to the fact that the valence electron bonding isn’t strong enough to hold all of its electrons.
Sun Nov 01, 2020 10:56 am
Forum: Lewis Structures
Topic: Using Lewis Structures
Replies: 7
Views: 62

### Re: Using Lewis Structures

Yes, lewis structures can be used to represent ionic bonds similar to the example that Professor Lavelle demonstrated in the previous lecture during week 4.
Sun Nov 01, 2020 10:54 am
Forum: Lewis Structures
Topic: Octet Rule
Replies: 12
Views: 74

### Re: Octet Rule

The octet rule does not apply to the elements of H, He, Li, and Be. While there may be more elements that do not apply to the octet rule like Boron, Professor has only discussed these four so far.
Sun Nov 01, 2020 10:43 am
Forum: Ionic & Covalent Bonds
Topic: Homework due date
Replies: 49
Views: 336

### Re: Homework due date

I am pretty sure it means that it is due Sunday at 11:59pm just like our five post in chem community.
Sun Nov 01, 2020 10:37 am
Forum: Ionic & Covalent Bonds
Topic: Octet Rule Lecture 12
Replies: 7
Views: 44

### Re: Octet Rule Lecture 12

Yes that is true, the octet rule applies to Boron because of the three valence electrons that it possesses.
Sun Nov 01, 2020 10:34 am
Forum: Ionic & Covalent Bonds
Topic: Non Metals
Replies: 10
Views: 92

### Re: Non Metals

They do not lose any electrons due to their ionization energy. The bonds are stronger because of they have more pull/attraction making them to be poor electric conductors.
Sun Nov 01, 2020 10:24 am
Forum: Ionic & Covalent Bonds
Topic: Ionic Vs. Covalent
Replies: 7
Views: 63

### Re: Ionic Vs. Covalent

Essentially, covalent bonds often share electrons between other elements while the ionic bonds simply take or give electrons off depending on the situation.
Sun Nov 01, 2020 10:21 am
Forum: Ionic & Covalent Bonds
Topic: Strength of bonds
Replies: 13
Views: 90

### Re: Strength of bonds

Hydrogen bonds are often have the weakest link while covalent bonds have the strongest link with each other. In addition, the bonds with single bonds are ideally weaker than triple bonds.
Thu Oct 29, 2020 7:42 am
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: 4s and 3d
Replies: 14
Views: 104

### Re: 4s and 3d

I believe the 3d would have to be filled up by an electron to its full capacity in order for the electron to go to the next energy level.
Sun Oct 25, 2020 9:17 pm
Forum: Quantum Numbers and The H-Atom
Topic: Emitting a Photon
Replies: 9
Views: 53

### Re: Emitting a Photon

The photon would be emitted once the excited electron begins to come down from its peak energy level, once it reaches normal state there will no longer any emitting that occur because all the photons have been emitted.
Sun Oct 25, 2020 9:14 pm
Forum: Photoelectric Effect
Topic: Intensity vs. Frequency
Replies: 22
Views: 140

### Re: Intensity vs. Frequency

The intensity is related to the number of photons of the light.
Sun Oct 25, 2020 9:10 pm
Forum: Photoelectric Effect
Topic: Mass of atoms
Replies: 18
Views: 105

### Re: Mass of atoms

I would stick with the SI units just in case because it is easier to work with the SI units.
Sun Oct 25, 2020 9:04 pm
Forum: Photoelectric Effect
Topic: Calculations
Replies: 18
Views: 97

### Re: Calculations

I think in regards of calculations, you will be fine if you are off by a few numbers. Best to refer to the answers to the multiple choice question if your calculation is slightly off.
Sun Oct 25, 2020 8:59 pm
Forum: DeBroglie Equation
Topic: n1 and n2
Replies: 15
Views: 56

### Re: n1 and n2

It will be easier to remind yourself that it should be final minus the initial.
Sun Oct 25, 2020 8:57 pm
Forum: DeBroglie Equation
Topic: Derivation of Equations on Midterm?
Replies: 17
Views: 99

### Re: Derivation of Equations on Midterm?

Our midterm will be all multiple choice, so I think everything we need in regards of equations will be provided and given to us on the equation and constants worksheet.
Sun Oct 25, 2020 8:54 pm
Forum: Student Social/Study Group
Topic: Final Jitters
Replies: 226
Views: 35945

### Re: Final Jitters

Often, I try to relax by changing the scenery where I am and surrounding myself with sounds that calm me down such as songs. Personally, I try to listen to my body and my mind in order to avoid over stressing and preventing anxiety attacks. Try to spread out your studying time as well.
Sun Oct 25, 2020 8:51 pm
Forum: Heisenberg Indeterminacy (Uncertainty) Equation
Topic: Midterm 1
Replies: 18
Views: 206

### Re: Midterm 1

I think you should master the equation just in case it will show up on the midterm. Since it was on the lecture, it is a possibility that it will be an equation that we may require to use during the midterm.
Sun Oct 25, 2020 8:48 pm
Forum: Heisenberg Indeterminacy (Uncertainty) Equation
Topic: When do we use Heisenberg indeterminacy equation
Replies: 10
Views: 70

### Re: When do we use Heisenberg indeterminacy equation

Based on my knowledge, we only use the Heisenberg indeterminacy equation once we are asked for the velocity.
Sun Oct 25, 2020 8:45 pm
Forum: Heisenberg Indeterminacy (Uncertainty) Equation
Topic: Uncertainty in percentage
Replies: 8
Views: 73

### Re: Uncertainty in percentage

Relying on the units will help with your confusion. Also, you can attempt to multiply the percentage to find the value of the uncertainty.
Sun Oct 18, 2020 8:36 pm
Forum: Einstein Equation
Topic: What are the units for E
Replies: 16
Views: 124

### Re: What are the units for E

Energy is usually given in Joules after calculations. If you are calculating for wavelength, the problem will often tell you to either give your answer in meters or nanometers.
Sun Oct 18, 2020 8:33 pm
Forum: Einstein Equation
Topic: m vs nm
Replies: 66
Views: 433

### Re: m vs nm

I believe it depends on what you are trying to calculate and what it is asking for. For the most part, it will probably ask for nanometers.
Sat Oct 17, 2020 10:27 am
Forum: Student Social/Study Group
Topic: How are you studying?
Replies: 203
Views: 1266

### Re: How are you studying?

Essentially, I think it is all about time management. Creating a time frame throughout the day for each of your classes can help you stay on top them. For chem, I try to watch the lecture twice, the first time trying to focus on writing all the information that I need and the second to pay attention...
Sat Oct 17, 2020 9:54 am
Forum: Photoelectric Effect
Topic: Excess energy
Replies: 20
Views: 135

### Re: Excess energy

That equation is the method to find kinetic energy. Professor Lavelle mentions that this calculation expresses the excess energy of the electron that is emitted. Please correct me if I am wrong, hope this helps.
Sat Oct 17, 2020 9:31 am
Forum: Properties of Light
Topic: Question regarding webcam
Replies: 8
Views: 94

### Re: Question regarding webcam

Based on the information I have gathered from my TA and Professor’s email, we do not necessarily need a webcam if we have another device that will show our workspace while taking the assessments.
Sat Oct 17, 2020 9:29 am
Forum: Properties of Light
Topic: rydberg equation
Replies: 7
Views: 61

### Re: rydberg equation

I believe during the Lecture, Professor Lavelle mentioned that he prefers to have it solved the way he did it to avoid easy mistakes that we could possibly make when using the rydberg equation.
Sun Oct 11, 2020 2:45 pm
Forum: Balancing Chemical Reactions
Topic: Naming compounds
Replies: 21
Views: 192

### Re: Naming compounds

Hello, I believe when it comes to being familiar with the compounds and basic elements, it will be beneficial for your growth in the course. In exams or quizzes, I do believe that we will be given this information in order to provide an answer to the question.
Sun Oct 11, 2020 2:42 pm
Forum: Balancing Chemical Reactions
Topic: Periodic Table
Replies: 50
Views: 482

### Re: Periodic Table

I do not think you need to memorize the periodic table. Although, you will probably memorize some of the elements because you constantly use them. Personally, I printed a copy of the periodic table and keep it next to me due to the fact that it is very handy when doing calculations.
Sun Oct 11, 2020 2:11 pm
Forum: Empirical & Molecular Formulas
Topic: How to go from molecular formula to empirical formula
Replies: 4
Views: 31

### Re: How to go from molecular formula to empirical formula

The empirical formula is rather just a more condensed version of the molecular formula. Ultimately, it just a simple division problem where you are dividing by the smallest integer of the element in the molecular formula of your compound. You should still be keeping the same ratio of the molecular f...
Sun Oct 11, 2020 1:58 pm
Forum: Empirical & Molecular Formulas
Topic: Calculation Errors for Empirical Formulas
Replies: 10
Views: 67

### Re: Calculation Errors for Empirical Formulas

I think it ultimately depends on how close you are. In this case, 2.8 would be a legitimate calculation close enough to 3 when analyzing ratios.
Sun Oct 11, 2020 1:54 pm
Forum: SI Units, Unit Conversions
Topic: SI Units
Replies: 13
Views: 125

### Re: SI Units

Yes, I believe since so because it is the system used throughout the world. It will probably be wise to use it to avoid confusion when researching.