## Search found 99 matches

Mon Mar 16, 2020 4:51 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Replies: 8
Views: 116

If there is no conductive solid already participating in the redox reaction, then you would need to [censored] an inert metal such as Pt(s)
Mon Mar 16, 2020 4:50 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Voltaic Cells
Replies: 3
Views: 91

### Re: Voltaic Cells

Yes, they are the same. The other kind of cell that was mentioned but not studied in class was the concentration cell.
Mon Mar 16, 2020 4:49 pm
Forum: Phase Changes & Related Calculations
Topic: state functions
Replies: 9
Views: 221

### Re: state functions

State functions, such as enthalpy, entropy, and Gibb's free energy, are dependent on the initial and final values. However, in the case of heat (q) and work which are pathway functions, the 'path' taken or how much is done is important.
Sun Mar 15, 2020 7:29 am
Forum: Balancing Redox Reactions
Topic: balancing h and o
Replies: 7
Views: 163

### Re: balancing h and o

Start off by balancing the oxygen atoms by using H20. From there depending on the pH, you use H+ for acidic solutions and OH^- for basic solutions to balance out the Hydrogens.
Sun Mar 15, 2020 7:26 am
Forum: Balancing Redox Reactions
Topic: OH vs H
Replies: 12
Views: 169

### Re: OH vs H

No, H+ is only used to balance a redox rxn in acidic conditions. In the case of a basic solution, you MUST use OH^-
Sun Mar 15, 2020 7:24 am
Forum: Balancing Redox Reactions
Topic: Pt in Cell Diagram
Replies: 10
Views: 201

### Re: Pt in Cell Diagram

Pt(s) is used when there is no conductive solid participating in the reaction. It is an inert metal, therefore will not affect the redox rxn.
Sun Mar 15, 2020 7:23 am
Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
Topic: E cell
Replies: 9
Views: 130

### Re: E cell

E° refers to standard conditions, such as 1M, 1atm, 25°C (This is found using the cathode-anode), while E is not under these same conditions and can be found using the Nernst equation. As long as you have one of them known, the Nernst equation can be used to find the other.
Sun Mar 15, 2020 7:19 am
Forum: Interesting Applications: Rechargeable Batteries (Cell Phones, Notebooks, Cars), Fuel Cells (Space Shuttle), Photovoltaic Cells (Solar Panels), Electrolysis, Rust
Topic: Electrolysis
Replies: 6
Views: 108

### Re: Electrolysis

It's on the outline, so it can appear on the final. However, I think as long as you understand the basics, you should be fine.
Sun Mar 15, 2020 7:17 am
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Enthalpy and Heat
Replies: 4
Views: 126

### Re: Enthalpy and Heat

enthalpy is the change in heat at constant pressure (at which is can be equal to ), while q is measure of heat under varying conditions.
Sun Mar 15, 2020 7:15 am
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: calculating delta H for an expansion
Replies: 3
Views: 116

### Re: calculating delta H for an expansion

You'll need to use the standard enthalpy of formation and the ∆Hr° = ∆H° $\sum$(products) - ∆H° $\sum$(reactants)
Sun Mar 15, 2020 7:12 am
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Bond Enthalpies and Standard Enthalpies of Formation
Replies: 2
Views: 102

### Re: Bond Enthalpies and Standard Enthalpies of Formation

If the values are not given, you might have to use the ∆G° = ∆H° - T∆S°equation to calculate enthalpy. If not, then the value might be zero. I don't believe there should be much confusion regarding this on the final.
Sun Mar 15, 2020 7:09 am
Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
Topic: Lyndon Review: 1D
Replies: 5
Views: 140

### Re: Lyndon Review: 1D

changing the size does not affect the cell potential
Sun Mar 15, 2020 7:08 am
Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
Topic: Same charge
Replies: 1
Views: 67

### Re: Same charge

First, make sure you balance the charges of each half reaction (for the most part you should need electrons to balance the half rxns). If then, you notice that both half rxns have the same charges then you should be fine as the electrons eventually cancel out.
Sun Mar 15, 2020 7:05 am
Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
Topic: Flipping the anode
Replies: 4
Views: 107

### Re: Flipping the anode

Since all the standard cell equations are written as reduction (which coincide with the cathodes), then the anode must be flipped to get the oxidation half reaction.
Sun Mar 15, 2020 7:03 am
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Including H2O in Cell Diagram
Replies: 3
Views: 48

### Re: Including H2O in Cell Diagram

Yes, H2O is not included in the cell diagram
Sun Mar 15, 2020 7:02 am
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Replies: 3
Views: 61

### Re: Adding H20 to solution

The effect of the dilution depends on where it is occurring. If the cathode is diluted then the cell potential decreased. However, if the anode is dilution there is an increase in cell potential.
Sun Mar 15, 2020 7:00 am
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Electrode Mass
Replies: 10
Views: 216

### Re: Electrode Mass

Changing the concentration of the electrode might result in an increase, however for the mass it should not affect cell potential.
Sat Mar 14, 2020 3:31 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: inert gases
Replies: 6
Views: 101

### Re: inert gases

Kaylee Clarke 1G wrote:what of the elements such as platinum that seem to be attached to a cell diagram?

Pt(s) is used as a conductor when there is no conductive solid participating in the redox reaction. It is added to the cell diagram but does not participate.
Sat Mar 14, 2020 3:28 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Cell Diagram
Replies: 11
Views: 153

### Re: Cell Diagram

Yes. Since Pt(s) is an inert metal, it is commonly used in the absence of a conductive solid.
Sat Mar 14, 2020 3:27 pm
Forum: Balancing Redox Reactions
Topic: Redox Reaction in a Basic Solution
Replies: 3
Views: 121

### Re: Redox Reaction in a Basic Solution

for basic solutions, you balance out the oxygens with H2O and then use OH^- to balance the hydrogens
Sat Mar 14, 2020 3:08 pm
Forum: Balancing Redox Reactions
Topic: Oxidation number
Replies: 12
Views: 252

### Re: Oxidation number

the oxidation number helps identify whether a species is oxidized or reduced. Using the oxidation number, you can determine how many electrons are necessary to balance the charges of a half reaction.
Sat Mar 14, 2020 3:06 pm
Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
Topic: Endgame 1a
Replies: 5
Views: 102

### Re: Endgame 1a

the anode is the side with the lower concentration as it is the side where oxidation occurs.
Sat Mar 14, 2020 3:04 pm
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: E vs Eo
Replies: 6
Views: 146

### Re: E vs Eo

Eº refers to standard conditions while E is not and therefore is affected by changes such as temperature, concentration etc.
Sat Mar 14, 2020 3:01 pm
Forum: Balancing Redox Reactions
Topic: Acid or base?
Replies: 5
Views: 173

### Re: Acid or base?

Yes, we will be given that information as it is necessary to determine how to balance the redox rxns. In some cases, we might be given the pH or even pka or pkb to determine pH.
Thu Mar 12, 2020 8:30 am
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: 6L.3
Replies: 4
Views: 79

### Re: 6L.3

You get the half reactions by looking at the species used in the galvanic cell. It helps to think about AnOX RedCat. The left side or anode is where the oxidation reaction occurs (a loss of electrons) and the right is where the reduction occurs (gaining of electrons).
Thu Mar 12, 2020 8:25 am
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Lavelle's review slides
Replies: 3
Views: 43

### Re: Lavelle's review slides

Pt(s) is an inert metal, so it won't affect the reaction but is necessary to serve as conductor.
Thu Mar 12, 2020 8:20 am
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: salt bridge
Replies: 11
Views: 83

### Re: salt bridge

The salt bridge is essentially meant to neutralize solutions and balance the charges which occur due to the transfer of electrons in a redox reaction.
Thu Mar 12, 2020 8:11 am
Forum: Balancing Redox Reactions
Topic: Determining the oxidizer and reducer
Replies: 10
Views: 105

### Re: Determining the oxidizer and reducer

Familiarize yourself with the LEO (loss of electron, oxidization) and GER (gains electrons, reduction) acronyms, they help identify what is being reduced and oxidized. From there you also have to know that the species that is being reduced in the 'oxidizing agent' and the one being oxidized is the '...
Thu Mar 12, 2020 8:07 am
Forum: Balancing Redox Reactions
Topic: Oxidation/Reduction
Replies: 17
Views: 260

### Re: Oxidation/Reduction

You take a look at the change in oxidation number. The molecule that is being reduce deceased in the oxidation number such as Cu2^+(aq)→ Cu(s), while the species being oxidized increases in the oxidation number Zn(s) → Zn2+(aq) *These examples can be found in RedOx reactions Part 1 sheet with furthe...
Thu Mar 12, 2020 7:47 am
Forum: Balancing Redox Reactions
Topic: Half Reactions
Replies: 15
Views: 148

### Re: Half Reactions

for half reactions you have to play attention on whether the solution is acidic or basic, this will tell you if you should use H+ and H2O (for acidic solutions) or OH- and H2O (for basic solutions). Start off with adding H2O to the side that needs it to balance out the O atoms. From there, depending...
Thu Mar 12, 2020 7:36 am
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: Finding k1 when given two temperatues
Replies: 6
Views: 129

### Re: Finding k1 when given two temperatues

You don't really KNOW which is T1 and K1, you more assign given values. Despite this, whichever you choose to be T1 and K1 must correlate with one another. I usually label the initial temp and k as T1 and K1, then the second temp as T2 to find K2 (the unknown value). As long as you keep the related ...
Thu Mar 12, 2020 7:22 am
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: Combustion of gas
Replies: 6
Views: 151

### Re: Combustion of gas

In the case of ∆G° = ∆H° - T∆S°, which indicates standard condition yes. The combustion of gas will be spontaneous due to the negative enthalpy value, the release of heat through an exothermic reaction, and a positive (increasing) entropy.
Thu Mar 12, 2020 7:11 am
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: G=-nFe
Replies: 7
Views: 123

### Re: G=-nFe

You have to look at the number of electrons transferred in the redox reaction. (Essentially, the number of electrons that balances the combined half-reactions.)
Thu Mar 12, 2020 7:09 am
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: dilutions and Ecell
Replies: 8
Views: 148

### Re: dilutions and Ecell

It is important to note where the dilution is occurring as it will affect cell potential differently if it is in the cathode or anode. You can use E˚(cell) = E˚(cathode) - E˚(anode) to get a better understanding. When the cathode is diluted, cell potential decreases due to the lower cathode. Therefo...
Thu Mar 12, 2020 7:03 am
Forum: Phase Changes & Related Calculations
Topic: delta G0 versus delta G
Replies: 15
Views: 423

### Re: delta G0 versus delta G

The "o" indicates standard conditions, (in temperature, pressure and concentration. ∆G° can be used to find ∆G and vice versa in the equation ∆G = ∆G° + RT ln Q
Thu Jan 30, 2020 4:17 pm
Forum: Phase Changes & Related Calculations
Topic: State Functions
Replies: 9
Views: 85

### Re: State Functions

Enthalpy is considered a state function as it is dependent on initial and final states.
Thu Jan 30, 2020 4:16 pm
Forum: Phase Changes & Related Calculations
Topic: Calculating Work
Replies: 6
Views: 65

### Re: Calculating Work

w=-P$\Delta$V
The equation for work has a negative. If the change in volume is also negative, then work will be positive. If not, then it will be negative.
Thu Jan 30, 2020 4:13 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Why can't qv equal delta H?
Replies: 3
Views: 60

### Re: Why can't qv equal delta H?

qv is at constant volume, with changing pressure, while delta H is heat transfer at constant pressure.
Thu Jan 30, 2020 4:11 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Delta H v. q
Replies: 5
Views: 71

### Re: Delta H v. q

q refers to the energy, as heat, transferred due to a change in temperature. $\Delta H$ is the heat transferred at constant pressure
Thu Jan 30, 2020 4:08 pm
Forum: Phase Changes & Related Calculations
Topic: Cv and Cp
Replies: 9
Views: 96

### Re: Cv and Cp

They are equal in the case of solids and liquids but change for gases due to compression and expansion.
Thu Jan 30, 2020 4:05 pm
Forum: Phase Changes & Related Calculations
Topic: Molar Heat Capacity at Cp s. Cv
Replies: 4
Views: 63

### Re: Molar Heat Capacity at Cp s. Cv

Both can be used for a gas, however they do not yield the same answer. The p subscript indicates constant pressure while the v is for volume.
Thu Jan 30, 2020 4:02 pm
Forum: Phase Changes & Related Calculations
Topic: Units
Replies: 16
Views: 161

### Re: Units

0°C= 273.15 K. When calculating change in temp, if you have 283.15K-276.15K or 10°C-3°C, the change in temperature is essentially the same.
Thu Jan 30, 2020 3:52 pm
Forum: Phase Changes & Related Calculations
Topic: 4A. 1 Identifying open and closed system
Replies: 11
Views: 269

### Re: 4A. 1 Identifying open and closed system

C is a closed system as the clariometer does not allow the transfer of energy to the suroundings.
Thu Jan 23, 2020 2:31 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Acids and Bases pka and pkb
Replies: 8
Views: 88

### Re: Acids and Bases pka and pkb

A lower pKa indicates a stronger acid and a lower pKb is a stronger base, as pKa + pKb = 14
Thu Jan 23, 2020 2:29 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: ice table
Replies: 13
Views: 93

### Re: ice table

They aren't included, since you wouldn't include them in the K expression.
Thu Jan 23, 2020 2:27 pm
Forum: Ideal Gases
Topic: ICE table approximation
Replies: 10
Views: 80

### Re: ICE table approximation

You take a look at the K value. If it is less than 10^-3, then you can approximate. If the K value is 10^-3, it can get a bit tricky, so I would still do the full calculation.
Thu Jan 23, 2020 2:25 pm
Forum: Ideal Gases
Topic: Equilibrium Constant
Replies: 7
Views: 73

### Re: Equilibrium Constant

Since K=products/reactants. A small K value indicated that the numerator is being divided by a large denominator. So there are more reactants.
Thu Jan 23, 2020 2:22 pm
Forum: Ideal Gases
Topic: PV=nRT
Replies: 13
Views: 148

### Re: PV=nRT

This in relation to concentration (n/V). It's used mainly to calculate for the unknown variable.
Thu Jan 23, 2020 2:19 pm
Forum: Ideal Gases
Topic: test 1
Replies: 9
Views: 120

### Re: test 1

No, test one is only for chemical equilibrium and acids and bases
Thu Jan 23, 2020 2:18 pm
Forum: Ideal Gases
Topic: Kc vs Kp
Replies: 43
Views: 567

### Re: Kc vs Kp

It depends on what asked and given. If you are calculating molar concentration then you would use Kc.
Thu Dec 05, 2019 5:51 pm
Forum: Naming
Topic: naming
Replies: 3
Views: 70

### Re: naming

When it comes to alphabetizing, you look at the beginning of the compound itself, not the prefixes used.
Thu Dec 05, 2019 5:48 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Ligand Names
Replies: 2
Views: 55

### Re: Ligand Names

I believe that the ligands on the table are the principle ones that may come up during the final.
Thu Dec 05, 2019 5:44 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Lone Pairs in this Compound
Replies: 2
Views: 70

### Re: Lone Pairs in this Compound

The subscript of two shows that there is double of what is inside the parentheses, therefore 2 N. The third one is the N that is on the outside in the HN.
Thu Dec 05, 2019 5:40 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: chelate
Replies: 2
Views: 58

### Re: chelate

It also includes bidentate complexes, as chelating ligands refers to those that can make multiple (2 or more) bonds to the central metal atom.
Thu Dec 05, 2019 5:37 pm
Forum: Naming
Topic: 9C 1A
Replies: 3
Views: 56

### Re: 9C 1A

iron is a naming exception when it comes to adding the -ate suffix, instead of ironate. We use the roman name of ferrum, then add the suffix.
Thu Dec 05, 2019 5:33 pm
Forum: Naming
Topic: Cyanido vs cyano
Replies: 5
Views: 77

### Cyanido vs cyano

I'm confused on these two terms. The textbook uses the form cyanido, but Lavelle wrote cyano for a naming example in lecture. Can they be used interchangeably, or are they different?
Thu Dec 05, 2019 5:30 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: -ate
Replies: 11
Views: 265

### Re: -ate

-ate is used with there is a negative charge on the complex and is added to the end of the TM
Thu Dec 05, 2019 5:29 pm
Forum: Naming
Topic: sodium bisoxalato(diaqua)ferrate(III) (homework 9C.3D)
Replies: 2
Views: 63

### Re: sodium bisoxalato(diaqua)ferrate(III) (homework 9C.3D)

3. I don't think there is a preference, but the textbook uses OH2 a lot, so i would stick with that format.
Sat Nov 23, 2019 4:15 pm
Forum: Hybridization
Topic: Hybridization with lone pairs on central atom
Replies: 6
Views: 103

### Re: Hybridization with lone pairs on central atom

Yes since the regions of electron density correlates with the hybridization. 2 regions=sp and so on like without lone pairs.
Sat Nov 23, 2019 4:08 pm
Forum: Hybridization
Topic: hybridization
Replies: 11
Views: 95

### Re: hybridization

You begin with the Lewis structure that will provide you with the regions of electron density of the center atom. Form their you can determine the hybridization. 2 regions corresponds with $sp$; 3= $sp^{2}$ and so on.
Sat Nov 23, 2019 4:05 pm
Forum: Hybridization
Topic: 2.57
Replies: 4
Views: 90

### Re: 2.57

For the right carbon you use $sp$ hybridized orbitals while the left carbon uses $sp^{3}$
Sat Nov 23, 2019 4:01 pm
Forum: Hybridization
Topic: Hybridization Structure
Replies: 3
Views: 46

### Re: Hybridization Structure

I was a little confused about that too.
Sat Nov 23, 2019 3:59 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: Problem 3F10 b
Replies: 6
Views: 109

### Re: Problem 3F10 b

Sydney Myers 4H wrote:
Daniel Martinez 1k wrote:Si2F2

Is this due to the shape? because Si2F2 would have a more linear structure, compared with a round structure of SiF4, and higher surface area makes for higher intermolecular forces, specifically London Dispersion Forces.

I believe this question is dependent on polarity, no shape for size.
Sat Nov 23, 2019 3:57 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: 3F 15
Replies: 5
Views: 194

### Re: 3F 15

This question has to do with polarity, not size. Since AsF3 is polar, it has stronger dipole-dipole interaction than AsF5, a nonpolar molecule.
Sat Nov 23, 2019 3:54 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 Rules
Replies: 6
Views: 87

### Re: Hydrogen Bonding Rules

A hydrogen bond can occur for one lone pair of N,O, and F. Therefore, a nitrogen atom with 2 lone pairs can form 2 hydrogen bonds.
Sat Nov 23, 2019 3:50 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: Homework 3F1
Replies: 4
Views: 87

### Re: Homework 3F1

The question is asking what are the IMF of each molecule. For H2SeO4, due to its polarity, it has dipole-dipole and induced-induced. On top of that, it can also form hydrogen bonds.
Sat Nov 23, 2019 3:47 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 forces
Replies: 9
Views: 101

### Re: london forces

London forces depends on the size of a molecule. Since larger molecules are more polarizable they form stronger London forces.
Sat Nov 23, 2019 3:44 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: 3F.5
Replies: 4
Views: 80

### Re: 3F.5

Butanol has a higher melting point, due to its ability to form hydrogen bonds.
Sat Nov 23, 2019 3:42 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: dipole-dipole vs induced dipole
Replies: 9
Views: 110

### Re: dipole-dipole vs induced dipole

Dipole-dipole interactions occur in polar molecules, while an induced dipole has to do with the uneven distribution of charges, resulting form a shift in electrons.
Sat Nov 23, 2019 3:38 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: Boiling Points
Replies: 9
Views: 135

### Re: Boiling Points

I'm confused between the melting point and the boiling point of a compound? Is this referring to the same thing?
Sat Nov 23, 2019 3:36 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 Atoms
Replies: 6
Views: 84

### Re: Hydrogen Bonding Atoms

Hydrogen bonds are formed between H and N,O,F atoms that have lone pairs.
Sat Nov 23, 2019 3:35 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: Best Approach to Find IMFs
Replies: 11
Views: 217

### Re: Best Approach to Find IMFs

It's good to start off drawing the Lewis Structure. From there you can determine whether the molecule is polar or nonpolar and capable of forming a hydrogen. If a molecule is polar then there is a dipole-dipole interaction. All molecule tend to have a induced-induced interaction.
Sat Nov 23, 2019 3:31 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: dipole-dipole in a solid phase vs gas phase
Replies: 15
Views: 285

### Re: dipole-dipole in a solid phase vs gas phase

The dipole-dipole interaction in the solid phase is stronger
Fri Nov 01, 2019 1:44 pm
Forum: Trends in The Periodic Table
Topic: Calculating Ionization Energy
Replies: 1
Views: 42

### Calculating Ionization Energy

In my discussion we did a problem that was essentially the following:
Calculate the ionization energy of RB given that a radiation with the wavelength of 58.4nm produces electrons with a velocity of 240km/s, when it hits RB.

Why do we solve for the work function?
Fri Nov 01, 2019 1:38 pm
Forum: Trends in The Periodic Table
Topic: Noble Gases
Replies: 10
Views: 158

### Re: Noble Gases

The noble gasses do not follow the trends of IE and EA due to their full valence shell which makes them pretty much unreactive.
Fri Nov 01, 2019 1:35 pm
Forum: Quantum Numbers and The H-Atom
Topic: 1D.17
Replies: 3
Views: 68

### Re: 1D.17

$m_{l}=-l,...0,...l$, so if the l= 1 then the magnetic numbers are -1,0,1
Fri Nov 01, 2019 1:30 pm
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: D orbital
Replies: 5
Views: 65

### Re: D orbital

If you take a look at the magnetic quantum numbers $m_{l}$ for the d, they are -2, -1, 0, +1, +2, which are 5 in total. Each orbital is able to hold 2 electrons, therefore the d-orbital can hold a total of 10 electrons.
Fri Nov 01, 2019 1:25 pm
Forum: DeBroglie Equation
Topic: Dino Nuggets Problem 8b
Replies: 11
Views: 494

### Re: Dino Nuggets Problem 8b

I got that far, as to find the Energy of the ejected electron, but how do I cancel the mol^-1 of the work function to be able to add it to the $E_{k}$?
Fri Nov 01, 2019 1:20 pm
Forum: *Shrodinger Equation
Topic: shrodinger equation
Replies: 4
Views: 88

### Re: shrodinger equation

Fri Nov 01, 2019 1:18 pm
Forum: Administrative Questions and Class Announcements
Topic: Accessing the E-textbook [ENDORSED]
Replies: 58
Views: 6122

### Re: Accessing the E-textbook[ENDORSED]

The sampling isn't mandatory but it is highly recommended as it provides you with extra practice and questions that are useful to study for the exams.
Fri Nov 01, 2019 1:16 pm
Forum: Heisenberg Indeterminacy (Uncertainty) Equation
Topic: What's the right equation?
Replies: 7
Views: 111

### Re: What's the right equation?

Fri Nov 01, 2019 1:07 pm
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: Electromagnetic Spectrum
Replies: 3
Views: 66

### Re: Electromagnetic Spectrum

I don't believe we have to know what frequencies correspond to what, but i do think it's good to be familiar with the visible light spectrum. This questions was more based on vaguely knowing the Balmer and Lymen series.
Fri Nov 01, 2019 1:04 pm
Topic: Info for Midterm
Replies: 12
Views: 346

### Re: Info for Midterm

No this will not be tested, since it was just briefly mentioned.
Fri Nov 01, 2019 1:01 pm
Forum: DeBroglie Equation
Topic: Dino Nuggets Problem 8b
Replies: 11
Views: 494

### Dino Nuggets Problem 8b

8. B) A newly designed laser pointer with a certain frequency is pointed at a sodium at a sodium metal surface. An electron is ejected from the metal surface with wavelength 1.10nm. What is the frequency of the light from the laser pointer? The work function of sodium is 150.6 kJmol^1. I understand ...
Fri Oct 18, 2019 6:45 pm
Forum: *Particle in a Box
Topic: Particle in A box
Replies: 8
Views: 279

### Re: Particle in A box

I think it's something that's meant to be more conceptual and help us understand what we are learning, not really something we have to focus a lot on since we didn't have questions on it.
Fri Oct 18, 2019 6:42 pm
Forum: Heisenberg Indeterminacy (Uncertainty) Equation
Topic: heisenberg, calculating kinetic energy
Replies: 3
Views: 49

### Re: heisenberg, calculating kinetic energy

It could be due because your velocity is not squared.
Fri Oct 18, 2019 6:38 pm
Forum: DeBroglie Equation
Topic: De Broglie's Equation
Replies: 17
Views: 270

### Re: De Broglie's Equation

A photon does not have mass which is required for the de Broglie's equation where $\lambda =\frac{h}{mv}$
Fri Oct 18, 2019 6:34 pm
Forum: Einstein Equation
Topic: HW 1B. 7
Replies: 6
Views: 309

### Re: HW 1B. 7

The new formula is derived from solving for the frequency in $c=\lambda \nu$ which gives you $\nu = c/\lambda$. You can then plug in this new value of $\nu$ into E=h$\nu$ to get $E=\frac{hc}{\lambda }$
Fri Oct 18, 2019 6:28 pm
Forum: Properties of Light
Topic: Unit for Wavelength
Replies: 34
Views: 416

### Re: Unit for Wavelength

Wavelength is measured in meters or other prefixes of meters such as nano and pico. It's easy to remember that units should cancel, c=λν which essentially is (m/s)=m x s^(-1)
Fri Oct 11, 2019 12:55 pm
Forum: Properties of Light
Topic: Clarification on Frequency
Replies: 8
Views: 169

### Re: Clarification on Frequency

Increasing the intensity of light will not change the frequency of a wave, it will only change the amplitude of the wave.
Fri Oct 11, 2019 12:50 pm
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: Test Equation Sheets
Replies: 5
Views: 86

### Re: Test Equation Sheets

An equation sheet will be provided during every test, so i don't think you have to worry much about memorizing the equations but more about how to apply them.
Fri Oct 11, 2019 12:47 pm
Forum: Properties of Light
Topic: Electromagnetic Spectrum
Replies: 5
Views: 82

### Re: Electromagnetic Spectrum

I don't believe we have to memorize the exact ranges, but possibly their placement based on wavelength. I do think you should know the range of visible light because it is common.
Fri Oct 11, 2019 12:44 pm
Forum: Accuracy, Precision, Mole, Other Definitions
Topic: Theoretical vs. Actual Yield
Replies: 38
Views: 3607

### Re: Theoretical vs. Actual Yield

The actual yield is less than the theoretical yield due to impurities and side reactants. I don't believe it's a concept you'll have to justify in the lab. You just need to familiarize yourself with it.
Fri Oct 11, 2019 12:39 pm
Forum: SI Units, Unit Conversions
Replies: 13
Views: 272

### Re: How to express answers

I'm still a little confused as to when I should use scientific notation or not. For example, the textbook solution for Fundamentals E.23 part a is 0.0134 mol Cu^2+, while the solution for E.23 part b is 8.74x10^-3. Why did they decide not to use scientific notation for part a? I've noticed that sci...
Fri Oct 04, 2019 1:37 pm
Forum: Limiting Reactant Calculations
Topic: General Limiting Reactant Question
Replies: 4
Views: 60

### Re: General Limiting Reactant Question

When there is only one reactant in an equation, there is no limiting reactant. When calculating the limiting reactant of a reaction with multiple reactants, you need to use mass and molar mass. Then you find the theoretical/maximum yield.
Fri Oct 04, 2019 1:32 pm
Forum: Accuracy, Precision, Mole, Other Definitions
Replies: 18
Views: 320

The question usually specifies which unit is preferred in the answer. If there is a certain question you are referencing, try posting it verbatim, in order to clear up the confusion.
Fri Oct 04, 2019 1:28 pm
Forum: Molarity, Solutions, Dilutions
Topic: Module: Molarity and Dilution of a solution
Replies: 5
Views: 107

### Re: Module: Molarity and Dilution of a solution

This question requires the M1V1=M2V2 as it is a dilution problem. The 5.00g is necessary to find the moles of KMnO4. From there, you can calculate the M1, divide your answer by .15L (after unit conversion of mL). The 20.00mL or .02000L is your V1, with the new volume 250mL or .250L as your V2
Fri Oct 04, 2019 1:17 pm
Forum: Molarity, Solutions, Dilutions
Topic: Fundamentals G5
Replies: 3
Views: 86

### Re: Fundamentals G5

I was confused on that question too, but you have to make sure to do a unit conversion of mmol to mol and to use the M=n/v. This question also required the use of the ratio of Na:Na2CO3, which is 2:1 and CO3:Na2CO3, 1:1.
Fri Oct 04, 2019 1:11 pm
Forum: SI Units, Unit Conversions
Topic: Why do we always need grams when solving a problem?
Replies: 6
Views: 105

### Re: Why do we always need grams when solving a problem?

The unit conversion is necessary for dimensional analysis. In a calculation that requires the use of a molecule's molecular weight, we cannot simply go from mg to moles. The mg nor the g would cancel out.