## Search found 54 matches

Sun Jan 10, 2021 10:29 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: Q and K
Replies: 21
Views: 63

### Re: Q and K

Yeah Q tells us the ratio of P/R concentrations at any time while K is the P/R concentrations at equilibrium. However, even though they may be calculated the same way knowing Q and K can tell us which direction the reaction tends to.
Sun Jan 10, 2021 10:25 pm
Forum: Ideal Gases
Topic: Non-Ideal gases?
Replies: 22
Views: 86

### Re: Non-Ideal gases?

I think Dr. Lavelle mentioned that this course would only deal with ideal gases since they are much easier to deal with conceptually and in terms of doing calculations.
Sun Jan 10, 2021 10:23 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Concentration vs Pressure
Replies: 9
Views: 23

### Re: Concentration vs Pressure

I think mathematically they follow the same process when calculating K, but conceptually Kc is defined by molar concentrations while Kp is defined using partial pressures of gasses.
Wed Dec 16, 2020 12:08 am
Forum: Student Social/Study Group
Topic: Study music
Replies: 32
Views: 159

### Re: Study music

I really like to listen to classical piano when studying for harder topics as it doesn't have lyrics but if I'm just working on normal assignments then I like to listen to a lot of contemporary music that I personally enjoy.
Wed Dec 16, 2020 12:07 am
Forum: Student Social/Study Group
Topic: Final Exam
Replies: 49
Views: 284

### Re: Final Exam

Yeah I definitely thought that this final was harder than the 2 previous midterms that we did. I was uncertain on a lot of questions and had to guess on a few which was pretty rough.
Wed Dec 16, 2020 12:04 am
Forum: Student Social/Study Group
Topic: Changing Study Habits
Replies: 35
Views: 163

### Re: Changing Study Habits

I need to stop cramming right before big tests as I have a tendency to push back a lot of work and studying a few days before tests which really makes me work a lot and not retain as much information as I could. I could also utilize more of the resources given as I only did textbook problems and wat...
Wed Dec 16, 2020 12:02 am
Forum: Student Social/Study Group
Topic: Curve
Replies: 29
Views: 200

### Re: Curve

I don't think there's a curve because of how the professor adds points to tests which should help regardless.
Wed Dec 16, 2020 12:02 am
Forum: Student Social/Study Group
Topic: Curve
Replies: 29
Views: 200

### Re: Curve

I don't think there's a curve because of how the professor adds points to tests which should help regardless.
Wed Dec 16, 2020 12:01 am
Forum: Student Social/Study Group
Topic: Winter Break
Replies: 44
Views: 230

### Re: Winter Break

I usually try not to look at school too much during break but if I forget important concepts before class then I would just briefly review my notes and online videos on the topics that I forgot.
Tue Dec 08, 2020 8:55 pm
Forum: Naming
Topic: Naming quizlet
Replies: 41
Views: 253

### Re: Naming quizlet

Thanks this helps a lot with practicing.
Tue Dec 08, 2020 8:54 pm
Forum: Naming
Topic: Naming metals
Replies: 6
Views: 43

### Re: Naming metals

For coordinate compounds the metal goes at the end of the bracket, but not always at the end of the molecule which is the key distinction.
Tue Dec 08, 2020 8:52 pm
Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
Topic: dipole-dipole molecule
Replies: 2
Views: 19

### Re: dipole-dipole molecule

Dipole-dipole attractions occur when the partial positive of one molecule is attracted to the partial negative of another. This often occurs between 2 polar molecules which you can determine to be polar based on the structure of the molecule.
Tue Dec 08, 2020 8:46 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: Why are hydrogen bonds so strong relative to other dipole-dipole bonds?
Replies: 11
Views: 128

### Re: Why are hydrogen bonds so strong relative to other dipole-dipole bonds?

Compared to other dipole-dipole bonds, the electronegativity difference between hydrogen and O/F/N is very high which makes for stronger bonds which play a huge role in biological and chemical molecules such as DNA.
Tue Dec 08, 2020 8:43 pm
Forum: Naming
Topic: What if I don't know?
Replies: 8
Views: 87

### Re: What if I don't know?

Yeah I'm fairly certain if there is a complicated compound that we're not expected to know the name will be given to us.
Sun Nov 29, 2020 9:08 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Bond Angles
Replies: 4
Views: 29

### Re: Bond Angles

The shape of molecules and lone pairs determines the bond angles. The best way to get familiar with them is just by practicing I think since there isn't any way to calculate the bond angles.
Sun Nov 29, 2020 9:05 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: London Dispersion
Replies: 33
Views: 137

### Re: London Dispersion

London dispersion forces are always present between molecules as the distribution of electrons is random within atoms which can create moments of instantaneous dipoles and induced dipoles. This can occur even with other intermolecular forces present.
Sun Nov 29, 2020 9:01 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Molecular Shape
Replies: 12
Views: 60

### Re: Molecular Shape

Lone pairs are more repulsive than bond pairs which can alter bond angles and the overall shape of molecules which can affect the polarity and other factors which makes lone pairs really important.
Sun Nov 29, 2020 8:58 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: H20 Shape
Replies: 17
Views: 98

### Re: H20 Shape

H2O has the two lone pairs on the central atom which repels the hydrogens causing the molecule to be bent instead of linear. If there were no lone pairs then the molecule would be linear.
Sun Nov 29, 2020 8:56 pm
Forum: Dipole Moments
Topic: What are dipole moments
Replies: 9
Views: 69

### Re: What are dipole moments

A dipole moment is the polarity of a molecule which is important to know because polarity determines how well molecules bond which determines a lot of chemical structures.
Sun Nov 29, 2020 8:49 pm
Forum: Dipole Moments
Topic: Tetrahedral Atoms and Dipole Moments
Replies: 7
Views: 41

### Re: Tetrahedral Atoms and Dipole Moments

I think so because the dipoles wouldn't be able to cancel out due to the atoms having different electronegativities which would slightly alter bond angles and make the molecular polar.
Sun Nov 29, 2020 8:48 pm
Forum: Hybridization
Topic: Definition of Hybridization
Replies: 5
Views: 59

### Re: Definition of Hybridization

Hybridization is the mixing of atomic orbitals (hybridization) to better suit electron pairing to form bonds.
Sun Nov 29, 2020 8:45 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Polarity
Replies: 17
Views: 73

### Re: Polarity

If there is a net dipole moment in a direction then the molecular is polar. This usually occurs if the molecule is asymmetrical in shape.
Sun Nov 29, 2020 8:42 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Bond angles
Replies: 7
Views: 29

### Re: Bond angles

Yeah I think you just need to look at the shape and lone pairs which gives u the bond angles which were found from previous experiments. You don't need to calculate or know exactly how the bond angles were found just know that they maximize repulsion.
Sun Nov 29, 2020 8:38 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: How do bonds affect shapes?
Replies: 11
Views: 64

### Re: How do bonds affect shapes?

I don't think whether a bond is a single, double, or triple affects the shape of the molecule. However do know that double and triple bonds are shorter and stronger than single bonds.
Sun Nov 29, 2020 8:36 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: ions
Replies: 8
Views: 60

### Re: ions

I don't think whether a molecular is positive or negative affects the shape. You should just be looking for electron bonding pairs and lone electron pairs which affect molecular shape.
Sun Nov 15, 2020 10:42 pm
Forum: Electronegativity
Topic: polar vs nonpolar
Replies: 19
Views: 69

### Re: polar vs nonpolar

I think the electronegativity difference has to be higher than or equal to 0.5 and lower than 1.6 for a bond to be considered polar.
Sun Nov 15, 2020 10:39 pm
Forum: Ionic & Covalent Bonds
Topic: Hydrogen Bonding
Replies: 13
Views: 65

### Re: Hydrogen Bonding

F, O, and N have very high electronegativity differences relative to H which leads to a strong polar covalent bond, or a hydrogen bond.
Sun Nov 15, 2020 10:33 pm
Forum: Ionic & Covalent Bonds
Topic: Bond Length
Replies: 6
Views: 42

### Re: Bond Length

A shorter bond length is more stable because shorter bond lengths have higher energy which is harder to break and therefore more stable.
Sun Nov 15, 2020 10:30 pm
Forum: Ionic & Covalent Bonds
Replies: 18
Views: 108

I think adding electrons to an atom makes the ionic radius bigger as the added electrons repel from the already existing electrons while taking away electrons from an atom makes the radius smaller because there is less electron shielding so electrons get pulled closer to the nucleus.
Sun Nov 08, 2020 10:52 pm
Forum: Ionic & Covalent Bonds
Topic: London dispersion forces
Replies: 12
Views: 55

### Re: London dispersion forces

London dispersion forces occur when the electrons in atoms form temporary dipoles due to chance. This force is the weakest intermolecular force.
Sun Nov 08, 2020 10:44 pm
Forum: Ionic & Covalent Bonds
Topic: Chemical Bonds
Replies: 12
Views: 63

### Re: Chemical Bonds

Double bonds have more electrons than single bonds so they exert more force on the nucleus which pulls atoms closer together and makes the bond shorter.
Sun Nov 08, 2020 10:42 pm
Forum: Ionic & Covalent Bonds
Replies: 38
Views: 214

Going across a period nuclear charge increases due to the addition of more protons while electron shielding remains constant which causes a causes electrons to be pulled closer to the nucleus making the atomic radius smaller.
Sun Nov 08, 2020 10:37 pm
Forum: Ionic & Covalent Bonds
Topic: Difference Between Ionic & Covalent Bonds
Replies: 11
Views: 61

### Re: Difference Between Ionic & Covalent Bonds

Ionic bonds form when an atom transfers an electron to another to form a bond where covalent bonds form when atoms share electrons. Ionic bonds are usually formed between a metal and nonmetal where ionic bonds are formed between 2 nonmetals.
Sun Nov 01, 2020 10:16 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Simplifying Electron Configurations
Replies: 9
Views: 66

### Re: Simplifying Electron Configurations

The noble gas represents a full and therefore stable valence shell which is unique to noble gases which is why we use noble gases to shorten electron configurations.
Sun Nov 01, 2020 10:12 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Noble Gas Configuration
Replies: 13
Views: 75

### Re: Noble Gas Configuration

I think doing either is fine, but if you are asked to write the electron configuration of a noble gas you should use the previous noble gas or write the entire configuration as the question is testing you on writing electron configurations.
Sun Nov 01, 2020 10:06 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: s and d orbitals in electron configurations
Replies: 9
Views: 60

### Re: s and d orbitals in electron configurations

You want to order the orbitals in order of increasing energy. So 3d^1 would be before 4s^2.
Sun Nov 01, 2020 9:58 pm
Forum: *Particle in a Box
Topic: Energy Equations
Replies: 9
Views: 101

### Re: Energy Equations

You can use either equation to get the energy of a particle but I don't think you can use E=pc for photons as photons have no mass and therefore no momentum.
Sun Nov 01, 2020 9:55 pm
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: Electron affinity
Replies: 4
Views: 36

### Re: Electron affinity

I think energy is released because adding electrons to an atom can make it more stable and stable atoms have less energy than other states. As a result the difference in energy is released when an atom accepts an electron to be more stable.
Sun Oct 25, 2020 8:58 pm
Forum: *Shrodinger Equation
Topic: Application of Shrodinger's Equation
Replies: 3
Views: 63

### Re: Application of Shrodinger's Equation

Yeah I'm pretty sure we only have to understand it conceptually as it is a pretty high level quantum physics equation with calculus.
Sun Oct 25, 2020 8:56 pm
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: Amplitude
Replies: 16
Views: 85

### Re: Amplitude

Changing a wave's amplitude only affects the intensity of that wave. The frequency of a wave is how many cycles there are in a given time frame and wavelength is the distance between the crests or troughs. The frequency/wavelength of a wave affects the energy as a higher frequency/lower wavelength w...
Sun Oct 25, 2020 8:52 pm
Forum: DeBroglie Equation
Topic: Derivation of Equations on Midterm?
Replies: 17
Views: 99

### Re: Derivation of Equations on Midterm?

Most likely the equations would be given so we don't have to derive anything. However it's good to know where the equations came from to have a better fundamental understanding of the concepts.
Sun Oct 25, 2020 8:48 pm
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: Bohr theory of the atoms
Replies: 4
Views: 40

### Re: Bohr theory of the atoms

Yeah, Bohr's model explained that when an electron moves from a higher energy level to a lower one, energy is emitted.
Sun Oct 25, 2020 8:45 pm
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: Lyman and Balmer Series
Replies: 5
Views: 48

### Re: Lyman and Balmer Series

I think you only have to know the Lyman and Balmer series but you should also know in general what the hydrogen spectral series are.
Sun Oct 18, 2020 10:41 pm
Forum: Properties of Light
Topic: Remembering EM spectrum
Replies: 6
Views: 62

### Re: Remembering EM spectrum

I don't think you should memorize the exact wavelengths and frequencies for each of EM radiation, but you should have a general idea on which waves have higher/lower frequencies and energies.
Sun Oct 18, 2020 10:34 pm
Forum: Einstein Equation
Topic: unexpected outcome of wave-particle experiment
Replies: 8
Views: 53

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

The photoelectric effect experiment demonstrated that photons can act as particles instead of just waves as the experiment showed individual photons interacting with individual electrons. Increasing the light intensity doesn't change the energy per photon but just the overall total sum of energy. Be...
Sun Oct 18, 2020 10:21 pm
Forum: Properties of Electrons
Topic: The Quantum World
Replies: 7
Views: 36

### Re: The Quantum World

Does anyone know how an electron can be emitted with 0 kinetic energy? Does it just stay in place or is it something else.
Sun Oct 18, 2020 10:15 pm
Forum: Properties of Light
Topic: energy level transfer
Replies: 7
Views: 36

### Re: energy level transfer

From a mathematical standpoint, the limit of the function as n approaches infinity is 0 because as the denominator of the function gets closer and closer to infinity, you get closer and closer to 0. From a conceptual standpoint I think energy approaches 0 as n goes to infinity because the energy lev...
Sun Oct 18, 2020 10:07 pm
Forum: Student Social/Study Group
Topic: How are you studying?
Replies: 203
Views: 1250

### Re: How are you studying?

I watch the lectures and take notes as well as do the homework assignments. I also read the textbook and do practice problems if I have extra time. Finally, if I am struggling on a concept or problem I try and learn more about it from the internet.
Fri Oct 09, 2020 4:01 pm
Forum: Balancing Chemical Reactions
Topic: State of matter in reaction
Replies: 9
Views: 37

### Re: State of matter in reaction

No the state of matter doesn't affect balancing equations but is still useful information to know for the overall reaction.
Fri Oct 09, 2020 3:59 pm
Forum: Limiting Reactant Calculations
Topic: Limiting reactants in all chemical rxns?
Replies: 18
Views: 147

### Re: Limiting reactants in all chemical rxns?

It would be very difficult for a reaction to not have a limiting reactant as getting the exact same quantity of all reactants is nearly impossible. You could theoretically have an infinite quantity of reactants which would get rid of the limiting reactant.
Fri Oct 09, 2020 3:48 pm
Forum: Balancing Chemical Reactions
Topic: Types of Chemical Reactions
Replies: 8
Views: 98

### Re: Types of Chemical Reactions

I think we will go over the different types of chemical reactions briefly as Dr. Lavelle usually goes over all the basics. But I also think it would be a good idea to review them a little bit beforehand.
Fri Oct 09, 2020 3:42 pm
Forum: Empirical & Molecular Formulas
Topic: Empirical and Molecular Formula
Replies: 17
Views: 124

### Re: Empirical and Molecular Formula

Is there ever a situation where the empirical formula would be used over the molecular formula?
Fri Oct 09, 2020 3:40 pm
Forum: Molarity, Solutions, Dilutions
Topic: Removing a part of a solution and diluting it?
Replies: 7
Views: 47

### Re: Removing a part of a solution and diluting it?

Yeah when diluting a solution the moles of solute always remain the same. So knowing that molarity = (moles of solute)/(liters of solution) and rearranging to solve for moles of solute gets us moles of solute = (molarity)(liters of solution) or MV. Then we get the equation M1V1 = M2V2 where M1/M2 ar...
Fri Oct 09, 2020 3:39 pm
Forum: Molarity, Solutions, Dilutions
Topic: Removing a part of a solution and diluting it?
Replies: 7
Views: 47

### Re: Removing a part of a solution and diluting it?

Yeah when diluting a solution the moles of solute always remain the same. So knowing that molarity = (moles of solute)/(liters of solution) and rearranging to solve for moles of solute gets us moles of solute = (molarity)(liters of solution) or MV. Then we get the equation M1V1 = M2V2 where M1/M2 ar...