## Search found 71 matches

Sun Jan 17, 2021 8:05 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: Q and K
Replies: 45
Views: 143

### Re: Q and K

Yes Q is a constant for the reaction at a time not at equilibrium which is compared to k in order to see which direction the reaction is shifting towards.
Sun Jan 17, 2021 8:04 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: ice tables
Replies: 7
Views: 26

### Re: ice tables

I make sure to double check the coefficients so I dont mess up the change expressions. I also check to see which way the reaction is shifted towards so I know which concentrations are decreasing and increasing.
Sun Jan 17, 2021 8:01 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Sapling Week 1 #3
Replies: 9
Views: 43

### Re: Sapling Week 1 #3

I used an ICE table to solve this question. You know the initial concentrations by dividing moles/Liters and you have the coefficients which will give u the change. Then you can set up an expression that you can set equal to Kc which is [HI]^2/[H2][I2]
Sun Jan 17, 2021 7:58 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Pressure Increase
Replies: 7
Views: 16

### Re: Pressure Increase

If inert gases were in the reaction, then the reaction will not shift right or left. it will only shift if the pressure change is due to a change in volume.
Sun Jan 17, 2021 7:53 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Exothermic vs Endothermic
Replies: 13
Views: 33

### Re: Exothermic vs Endothermic

A reaction is endothermic if it requires energy to run. Exothermic reactions release energy. delta H is negative in a exothermic reaction and positive in an endothermic reaction.
Sun Jan 10, 2021 10:11 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Changing pressure by adding gas
Replies: 13
Views: 53

### Re: Changing pressure by adding gas

There needs to be a change in volume to have a change in concentration so adding gases wont shift the reaction.
Sun Jan 10, 2021 10:08 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: reaction quotient
Replies: 6
Views: 18

### Re: reaction quotient

The Q is the ratio of products to reactants at a point other than equilibrium. This value is compared to K to see if the reaction will favor the reactants or products.
Sun Jan 10, 2021 10:02 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: K Favors Products or Reactants
Replies: 20
Views: 67

### Re: K Favors Products or Reactants

Large is greater than 10^3 and small is less than 10^-3
Sun Jan 10, 2021 10:02 pm
Forum: Ideal Gases
Topic: T variable in pv=nrt [ENDORSED]
Replies: 38
Views: 270

### Re: T variable in pv=nrt[ENDORSED]

I usually tend to keep it in Kelvin.
Sun Jan 10, 2021 10:01 pm
Forum: Ideal Gases
Topic: Sapling Homework
Replies: 22
Views: 167

### Re: Sapling Homework

I bought the package last quarter so this quarter I just used my credit from when I bought it. It gave me that option.
Thu Dec 17, 2020 12:34 am
Forum: Identifying Acidic & Basic Salts
Topic: rules for determining
Replies: 6
Views: 61

### Re: rules for determining

Look to see if it donates or accepts hydrogen ions.
Thu Dec 17, 2020 12:33 am
Forum: Identifying Acidic & Basic Salts
Topic: Identifying Salt pH
Replies: 6
Views: 52

### Re: Identifying Salt pH

I think this is the correct way it works.
Thu Dec 17, 2020 12:32 am
Forum: Identifying Acidic & Basic Salts
Topic: Titration Graphs
Replies: 6
Views: 70

### Re: Titration Graphs

We need to know the stoichiometric point.
Thu Dec 17, 2020 12:31 am
Forum: Identifying Acidic & Basic Salts
Topic: Strong acid / base ion
Replies: 8
Views: 56

### Re: Strong acid / base ion

Yes if both the cation and anion is from a strong acid/base, then the pH will not change.
Thu Dec 17, 2020 12:29 am
Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
Topic: Difference between pH and pOH
Replies: 12
Views: 63

### Re: Difference between pH and pOH

pH and pOH are just scales that represent the concentration of H+ ions and OH- ions.
Thu Dec 10, 2020 7:09 pm
Forum: Calculating the pH of Salt Solutions
Topic: pH formula?
Replies: 46
Views: 934

### Re: pH formula?

The pH formula is -log[H+].
Thu Dec 10, 2020 7:06 pm
Forum: Amphoteric Compounds
Topic: Amphoteric: acid and/or base
Replies: 4
Views: 47

### Re: Amphoteric: acid and/or base

for a molecule to be amphoteric it needs to be able to act as a base or a acid so it needs to be a proton acceptor or a proton donor depending on what it reacts with. water is a good example as it can donate a hydrogen atom to become a hydroxide ion or accept an electron to become a hydronium ion.
Thu Dec 10, 2020 7:03 pm
Forum: Properties & Structures of Inorganic & Organic Bases
Topic: Which is the stronger acid?
Replies: 9
Views: 185

### Re: Which is the stronger acid?

Have more oxygens will delocalize the charge more and make it easier to break the bond which results in it being a stronger acid.
Thu Dec 10, 2020 7:02 pm
Forum: Properties & Structures of Inorganic & Organic Bases
Topic: Determining relative strengths of bases (6C 17)
Replies: 2
Views: 121

### Re: Determining relative strengths of bases (6C 17)

BrO- has a negative charge so it is more likely to be a proton acceptor than morphine making it a stronger base.
Thu Dec 10, 2020 6:58 pm
Forum: Properties & Structures of Inorganic & Organic Acids
Topic: Week 10 Sapling Q10
Replies: 6
Views: 41

### Re: Week 10 Sapling Q10

HBr is a strong acid and HBrO is not on the list of strong acids so HBr is stronger.
Thu Dec 10, 2020 6:55 pm
Forum: Properties & Structures of Inorganic & Organic Acids
Topic: pKa
Replies: 3
Views: 36

### Re: pKa

We dont have to memorize the actual number but we have to know the trends and what the pKa means for the strength of the acid.
Sun Dec 06, 2020 11:05 pm
Forum: Industrial Examples
Topic: Coordination compounds as Chemotherapy drugs
Replies: 9
Views: 834

### Re: Coordination compounds as Chemotherapy drugs

I think we just need to know about cisplatin and how it is used in chemotherapy treatments by disrupting cell replication.
Sun Dec 06, 2020 11:03 pm
Forum: Biological Examples
Topic: Hemoglobin
Replies: 12
Views: 226

### Re: Hemoglobin

Hemoglobin carries oxygen through the blood while Myoglobin carries oxygen through the muscles.
Sun Dec 06, 2020 11:02 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Prefixes
Replies: 9
Views: 58

### Re: Prefixes

I memorized them by making flashcards with the ligand names and the prefixes.
Sun Dec 06, 2020 11:01 pm
Forum: Naming
Topic: 9C.3
Replies: 3
Views: 37

### Re: 9C.3

I think its just the new IUPAC naming convention. It is still correct to use cyano.
Sun Dec 06, 2020 10:59 pm
Forum: Naming
Topic: ligand names
Replies: 4
Views: 31

### Re: ligand names

Im pretty sure we cant. We can only use the periodic table and equations sheet.
Mon Nov 30, 2020 12:09 pm
Forum: Naming
Topic: Using ido or o
Replies: 24
Views: 134

### Re: Using ido or o

-ido is the new IUPAC convention but it is not widely recognized yet so Dr. Lavelle said we can just use -o.
Mon Nov 30, 2020 12:07 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Memorizing Common Ligands
Replies: 6
Views: 60

### Re: Memorizing Common Ligands

I think we should memorize all of them because were not sure which ones are going to be tested on the final.
Mon Nov 30, 2020 12:05 pm
Forum: Biological Examples
Topic: Hemoglobin vs. Myoglobin
Replies: 29
Views: 220

### Re: Hemoglobin vs. Myoglobin

Hemoglobin carries more oxygen as it has 4 myoglobins and transports o2 in the blood. Myoglobin transports through the tissues.
Mon Nov 30, 2020 12:03 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Learning ligand names and charges
Replies: 5
Views: 76

### Re: Learning ligand names and charges

I think we should memorize them because I think it is important to know for our final as we most likely wont have the name sheet.
Mon Nov 30, 2020 12:02 pm
Forum: Naming
Topic: Chlorido vs. chloro
Replies: 11
Views: 97

### Re: Chlorido vs. chloro

In lecture today, Dr. Lavelle explained that chloro is more widely used but I think both are still accurate.
Mon Nov 30, 2020 12:27 am
Forum: Shape, Structure, Coordination Number, Ligands
Topic: coordination number
Replies: 13
Views: 87

### Re: coordination number

Yes, the coordination number is the amount of bonds.
Mon Nov 30, 2020 12:25 am
Forum: Naming
Topic: chelating ligand
Replies: 7
Views: 75

### Re: chelating ligand

It is chelating if it has more than one lone pair.
Mon Nov 30, 2020 12:24 am
Forum: Hybridization
Topic: Delocalized Pi Bond
Replies: 10
Views: 67

### Re: Delocalized Pi Bond

It is related to resonance structures because if the bond is delocalized, the electrons can move.
Mon Nov 30, 2020 12:22 am
Forum: Determining Molecular Shape (VSEPR)
Topic: Polarity and Dipole Moments
Replies: 4
Views: 38

### Re: Polarity and Dipole Moments

Thats how I think of it. If the dipoles are in opposite direction and of the same magnitude, they cancel out. If all dipole moments cancel out, then the molecule is non polar.
Mon Nov 30, 2020 12:21 am
Forum: Hybridization
Topic: PBr5
Replies: 6
Views: 43

### Re: PBr5

There are 5 regions of electron density in PBr5 so there are 5 hybridized orbitals.
Sun Nov 22, 2020 10:43 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: double bonding
Replies: 8
Views: 74

### Re: double bonding

double bonds dont necessarily mean the molecule is going to be bent. The molecule is bent when there are lone pairs on the central atom of molecule like H2O.
Sun Nov 22, 2020 10:40 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Sapling #1
Replies: 6
Views: 45

### Re: Sapling #1

The sulfur has a lone pair which changes the structure.
Sun Nov 22, 2020 10:38 pm
Forum: Hybridization
Topic: pi bonds
Replies: 12
Views: 203

### Re: pi bonds

They are shown in the p orbital because a pi bond is formed when 2 p orbitals overlap vertically.
Sun Nov 22, 2020 10:37 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Bond Angles
Replies: 21
Views: 104

### Re: Bond Angles

I dont think you can calculate them. We just know the relative bond angles based on the structure of the molecule.
Sun Nov 22, 2020 10:34 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: memorizing VSEPR models
Replies: 13
Views: 79

### Re: memorizing VSEPR models

I made flashcards and used quizlet.
Sun Nov 15, 2020 10:31 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 Sites
Replies: 4
Views: 21

### Re: Hydrogen Bonding Sites

Yes, that is what I do. The shape will have an impact on the bonding but I dont think we have to worry about that for this midterm.
Sun Nov 15, 2020 10:30 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: Sapling # 20
Replies: 6
Views: 75

### Re: Sapling # 20

There are LD forces because compounds have some of these forces. The compound is polar so there are dipole dipole forces
Sun Nov 15, 2020 10:29 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: Van der Waals vs London Dispersion
Replies: 10
Views: 39

### Re: Van der Waals vs London Dispersion

They are the same just different names
Sun Nov 15, 2020 10:28 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: Ionic Bond vs. Hydrogen Bonding
Replies: 10
Views: 40

### Re: Ionic Bond vs. Hydrogen Bonding

ionic bonds are stronger and take more energy to break so it would have a higher boiling point.
Sun Nov 15, 2020 10:20 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: lodon dispersion forces
Replies: 8
Views: 17

### Re: lodon dispersion forces

they are not permanent so it takes a low energy to break them
Sun Nov 08, 2020 11:11 pm
Forum: Octet Exceptions
Topic: Aluminum Chloride Structure
Replies: 4
Views: 19

### Re: Aluminum Chloride Structure

Boron and Aluminum can be electron deficient and not have a full valence shell. Since both atoms usually have only 6 valence electrons, they can act as an electron accepter.
Sun Nov 08, 2020 11:07 pm
Forum: Resonance Structures
Topic: formal charge
Replies: 5
Views: 15

### Re: formal charge

Yes, the formal charges should add up to the total charge of the molecule.
Sun Nov 08, 2020 11:05 pm
Forum: Ionic & Covalent Bonds
Topic: Chemical Bonds
Replies: 12
Views: 65

### Re: Chemical Bonds

Double bonds are stronger than single bonds so they pull the atoms closer to each other.
Sun Nov 08, 2020 11:04 pm
Forum: Lewis Structures
Topic: expanded/smaller octets
Replies: 6
Views: 25

### Re: expanded/smaller octets

Atoms that have d-orbitals can have an expanded octet.
Sun Nov 08, 2020 11:01 pm
Forum: Ionic & Covalent Bonds
Replies: 38
Views: 222

The number of protons increases as you move across a period so there is a stronger pull on the electrons making the atomic radius smaller.
Sun Nov 01, 2020 11:48 pm
Forum: Lewis Structures
Topic: Using Lewis Structures
Replies: 7
Views: 62

### Re: Using Lewis Structures

Yes, an example would be sodium chloride.
Sun Nov 01, 2020 11:44 pm
Forum: Ionic & Covalent Bonds
Topic: Non Metals
Replies: 10
Views: 92

### Re: Non Metals

non metals want to gain an electron to fill their shell as they have a high ionization energy.
Sun Nov 01, 2020 11:41 pm
Forum: Administrative Questions and Class Announcements
Topic: Midterm Scores
Replies: 28
Views: 268

### Re: Midterm Scores

I heard that we were going to get the scores after the last discussion section took the exam but since we have not gotten them yet, I have just been looking for an email from Dr. Lavelle.
Sun Nov 01, 2020 11:39 pm
Forum: Quantum Numbers and The H-Atom
Topic: Ionization Energy Trend
Replies: 6
Views: 54

### Re: Ionization Energy Trend

The elements down a group have electrons farther away from the nucleus so it is easier to remove and takes less ionization energy.
Sun Nov 01, 2020 11:36 pm
Forum: Trends in The Periodic Table
Topic: studying
Replies: 12
Views: 59

### Re: studying

The UA workshops are helpfully along with doing the textbook problems and reading.
Sun Oct 25, 2020 10:10 pm
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: Midterm 1 Prep
Replies: 9
Views: 85

### Re: Midterm 1 Prep

I would study the fundamentals that we learned along with up to 1D.2 in the textbook. This includes the photoelectric effect, the c=lambda(v) and E=hv equations, Bohr frequency condition, Heisenberg Indeterminacy principle, and the Schrodinger wave function.
Sun Oct 25, 2020 10:06 pm
Forum: DeBroglie Equation
Topic: De Broglie's Equation vs C=wavelength(v)
Replies: 8
Views: 75

### Re: De Broglie's Equation vs C=wavelength(v)

In the De Broglie equation, you are relating wavelength to momentum so when the question asks you to solve for speed or requires you to solve for speed as one of the steps of the question, you would use De Broglie.
Sun Oct 25, 2020 10:03 pm
Forum: Properties of Electrons
Topic: Schrodinger's wave equation
Replies: 4
Views: 46

### Re: Schrodinger's wave equation

I think the Schrodinger equation gives us a wave function for each orbital basically giving a complex math model for the location of each orbital.
Sun Oct 25, 2020 9:59 pm
Forum: Properties of Light
Topic: Textbook Questions and Midterm
Replies: 6
Views: 61

### Re: Textbook Questions and Midterm

We just need to go up to 1D.2 in the textbook which is the first couple of questions in 1D. The last material that we learned that will be fair game for the midterm is the basics of the Schrodinger wave function.
Sun Oct 25, 2020 9:57 pm
Forum: Photoelectric Effect
Topic: Sapling #4 how do I find the number of electrons
Replies: 3
Views: 41

### Re: Sapling #4 how do I find the number of electrons

When there is a maximum number of electrons ejected, the work function is equal to the energy per photon because the kinetic energy is 0. So you divide the total energy you were given divided by the energy for the work function (the energy per photon) resulting in the Joules canceling out leaving yo...
Sun Oct 18, 2020 10:02 pm
Forum: Properties of Electrons
Topic: Ionizing Electrons vs Ejecting Electrons
Replies: 6
Views: 47

### Re: Ionizing Electrons vs Ejecting Electrons

When an electron is ejected, the atom is ionized because an ejecting an electron will change the charge of the atom thus making it ionized since the charge of an electron is negative.
Sun Oct 18, 2020 9:59 pm
Forum: Photoelectric Effect
Topic: Light Intensity
Replies: 23
Views: 109

### Re: Light Intensity

Yes. They were only increasing the amount of photons which is the intensity not the frequency of light.
Sun Oct 18, 2020 9:57 pm
Forum: Einstein Equation
Topic: unexpected outcome of wave-particle experiment
Replies: 8
Views: 54

### Re: unexpected outcome of wave-particle experiment

The unexpected result was that increasing the intensity of the light did not release electrons but were released when the frequency of light was increased.
Sun Oct 18, 2020 9:49 pm
Forum: Student Social/Study Group
Topic: How are you studying?
Replies: 203
Views: 1284

### Re: How are you studying?

Hi, I take notes during the lecture and try to stay engaged with the lecture by asking questions in chemistry community. I usually try to read the text before the class and do the text book assignments on the weekends. For the midterm I am planning on reviewing the notes, textbook questions, sapling...
Fri Oct 16, 2020 10:49 am
Forum: Quantum Numbers and The H-Atom
Topic: Lecture 10/16
Replies: 4
Views: 69

### Lecture 10/16

In the question in the lecture where the question is asking to calculate the frequency of light emitted by a hydrogen atom when an electron transitions from the 4th to the second, I am a little confused on why the sign for the energy changed from negative to positive when we plugged it in to the E=h...
Sun Oct 11, 2020 10:24 pm
Forum: Molarity, Solutions, Dilutions
Topic: Stuck on Sapling HW
Replies: 14
Views: 199

### Re: Stuck on Sapling HW

I first converted grams of CuNO3 to moles then I used the equation M=n/V and rearranged it for V. Just plug in the values now and you should get the correct answer.
Sun Oct 11, 2020 10:20 pm
Forum: Balancing Chemical Reactions
Topic: Order of Balancing Rxns
Replies: 23
Views: 115

### Re: Order of Balancing Rxns

I start with balancing the ones that occur the least and mark my progress with tallies next to the question.
Sun Oct 11, 2020 4:13 pm
Forum: Molarity, Solutions, Dilutions
Topic: Formulas involved in Determining Solution Concentration
Replies: 8
Views: 86

### Re: Formulas involved in Determining Solution Concentration

When the problem gives an initial volume and initial moles and then asks you to either find the final volume or final moles, I use the M(initial)V(initial)=M(final)V(final) equation.
Thu Oct 08, 2020 12:01 am
Forum: Empirical & Molecular Formulas
Topic: Sapling Hw Week 1 #10
Replies: 20
Views: 283

### Re: Sapling Hw Week 1 #10

Also where can we learn to read such symbols or way of displaying a chemical reaction without the lettering we usually use? For 2-butanone and 3-methyl 3-hexyl, there are Carbon molecules in between each bond represented by the lines in the picture. Each Carbon molecules needs to have 4 bonds so ad...
Wed Oct 07, 2020 12:16 am
Forum: Significant Figures
Topic: When are sig figs applied?
Replies: 12
Views: 104

### Re: When are sig figs applied?

I was taught not to round until the end of a problem so I just apply sig figs when I am done solving.