## Search found 108 matches

Fri Mar 13, 2020 2:02 pm
Forum: Zero Order Reactions
Topic: catalyst
Replies: 5
Views: 161

### Re: catalyst

No, not all zero order reactions is dependent on a catalyst. A zero order reaction could also occur with an enzyme or a surface. It's just that most commonly you would find a catalyst with a zero order reaction.
Fri Mar 13, 2020 2:00 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Endgame review packet, question 2b
Replies: 2
Views: 72

### Re: Endgame review packet, question 2b

For E cell, I got 2.05 V because the Ce is the cathode and Fe is the anode so it will be 1.61V - (-0.44V) = 2.05V. Since my E cell is different than yours, I also got a different delta G and K. For delta G, I got -396 kJ/mol and for K I got 2.6 x 10^69
Thu Mar 12, 2020 12:22 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: 5I.29
Replies: 3
Views: 151

### Re: 5I.29

You would use ICE to solve this problem and use 0.22 bar for HCl as the initial partial pressure. The initial partial pressure for H2 and Cl2 would be 0. Then for equilibrium you would use -2x for HCl and x for H2 and Cl2. Then you would set it equal to K and solve for the equilibrium partial pressu...
Thu Mar 12, 2020 12:18 pm
Forum: General Rate Laws
Topic: Factors Affecting k
Replies: 83
Views: 452

### Re: Factors Affecting k

Yes, the rate constant can change. It can change due to temperature. The rate constant is related to temperature through the Arrhenius equation.
Thu Mar 12, 2020 11:31 am
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: Battery
Replies: 19
Views: 363

### Re: Battery

Yes, a dead battery means that the reaction is at equilibrium so E potential is 0 and so is delta G.
Sun Mar 08, 2020 6:42 pm
Forum: Reaction Mechanisms, Reaction Profiles
Topic: Slow step vs. fast step
Replies: 3
Views: 79

### Slow step vs. fast step

How can determine which step is a slow step or fast step? What does fast step of a reaction mean?
Sun Mar 08, 2020 6:26 pm
Forum: Arrhenius Equation, Activation Energies, Catalysts
Topic: A in the Arrhenius Equation
Replies: 3
Views: 85

### Re: A in the Arrhenius Equation

The A stands for the frequency of collisions that occurs with the correct orientation or is the pre-exponential factor which is a constant for the reaction
Sun Mar 08, 2020 6:25 pm
Forum: Method of Initial Rates (To Determine n and k)
Topic: How to determine order
Replies: 3
Views: 92

### Re: How to determine order

One way to determine the order of the reaction is to look at the differential rate law. The general form for the differential rate law is k[R]^n and n is the order of the reactant or how many reactants are needed to form a product. So, if n = 1 then it is a first order reaction and if n = 2 then it ...
Sun Mar 08, 2020 6:18 pm
Forum: Reaction Mechanisms, Reaction Profiles
Topic: K’ for multi step reactions
Replies: 1
Views: 52

### Re: K’ for multi step reactions

The K' for multi step reactions would be the reverse rate of the overall K that we get at the end. For instance, in class the K overall we got was [D] /[A][B]. Then at equilibrium, it would be k[A][B] = k'[D] and then you could solve for k'.
Sun Mar 08, 2020 6:15 pm
Forum: Zero Order Reactions
Topic: slope of zero order reaction
Replies: 2
Views: 68

### Re: slope of zero order reaction

The slope of a zero order reaction is always negative because the equation we derived in class is equal to -k and since k must be positive all the time the slope of a zero order reaction is always negative since a zero order reaction doesn't depend on reactant concentration there's nothing to change...
Wed Feb 26, 2020 10:56 pm
Forum: Balancing Redox Reactions
Topic: OH- in Basic Solutions
Replies: 6
Views: 128

### Re: OH- in Basic Solutions

First you would add H2O to balance your oxygens. Then you would add H+ to balance your H and then you would add OH- to both sides because of alkaline or basic solution
Wed Feb 26, 2020 10:53 pm
Forum: Balancing Redox Reactions
Topic: How to tell if its being reduced or oxidized
Replies: 15
Views: 302

### Re: How to tell if its being reduced or oxidized

No because the charge of Mn in MnO4- is +7 and so Mn is going from a +7 charge to a +2 charge which means that it is gaining electrons for the charge to be less positive. So Mn is being reduced. You have to look at the charges individually if it is a compound and not the overall charge of the compou...
Wed Feb 26, 2020 10:50 pm
Forum: Balancing Redox Reactions
Topic: When to add H+ or H20
Replies: 19
Views: 444

### Re: When to add H+ or H20

You add H2O to balance the amount of oxygens and you do this step first. Then you add H+ to balance the amount of hydrogens.
Wed Feb 26, 2020 10:42 pm
Forum: General Science Questions
Topic: Test 2
Replies: 16
Views: 400

### Re: Test 2

It's going to cover the second page of thermodynamics and electrochemistry!
Wed Feb 26, 2020 10:41 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Homework 6L.9
Replies: 4
Views: 92

### Re: Homework 6L.9

So if we start off with an equation: 2KMnO4 + 8FeCl2 --> 2KCl + 2MnCl2 + 8FeO + 5Cl2. Through this equation you would see that your potassium value doesn't change, its charge is still +1. You also notice that the charge of Cl doesn't change and that it is still -1. That means MnO4 and Fe are your ca...
Wed Feb 26, 2020 10:29 pm
Forum: Balancing Redox Reactions
Topic: 6N.5
Replies: 2
Views: 84

### Re: 6N.5

Cl2 would have a charge of -2 because one Cl would have the charge of -1. So therefore one Hg would have the charge of +1 and Hg2 would have the charge +2 because overall the compound is neutral
Wed Feb 26, 2020 10:25 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: cell diagram
Replies: 4
Views: 147

### Re: cell diagram

So the order of a cell diagram would be solid|gas|aqueous || aqueous|gas|solid. The two lines in the middle represent the salt bridge and the left side represents the anode and the right side represents the cathode. A cell bridge is just another way to represent the transfer of electrons from an an...
Thu Feb 20, 2020 2:52 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Standard reduction potential
Replies: 2
Views: 67

### Standard reduction potential

Since the standard reduction potential is an intensive property, does that mean after we complete the reaction it stays constant and never changes again? If it does change again, what causes that change?
Thu Feb 20, 2020 2:47 pm
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: 6L.3 part c
Replies: 1
Views: 34

### Re: 6L.3 part c

The half reactions would be O2 + 2H2O + 4e- --> 4OH- and O2 + 4H+ 4e- --> 2H2O. You would just ignore the Pt because we add the Pt in the cell diagram because we needed a solid.
Thu Feb 20, 2020 2:34 pm
Forum: Gibbs Free Energy Concepts and Calculations
Topic: gas constant for gibbs free energy
Replies: 5
Views: 113

### Re: gas constant for gibbs free energy

Yes, because the units for Gibbs free energy is J/mol or kJ/mol and you cancel out the K with temperature.
Thu Feb 20, 2020 2:31 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: cell diagram
Replies: 4
Views: 147

### Re: cell diagram

So the order of a cell diagram would be solid|gas|aqueous || aqueous|gas|solid. The two lines in the middle represent the salt bridge and the left side represents the anode and the right side represents the cathode. A cell bridge is just another way to represent the transfer of electrons from an ano...
Thu Feb 20, 2020 2:26 pm
Forum: Gibbs Free Energy Concepts and Calculations
Topic: 5G.15
Replies: 5
Views: 114

### Re: 5G.15

I'm pretty sure the answer key is wrong because I also got -2.7 kJ/mol and the other people I asked also got -2.7 kJ/mol. Also, in my answer key, someone added a decimal point.
Thu Feb 20, 2020 2:22 pm
Forum: Gibbs Free Energy Concepts and Calculations
Topic: 5G.15
Replies: 5
Views: 89

### Re: 5G.15

For 5G.15, for the standard GFE I got -12.35 kJ and for my final answer, I actually got -2.7 kJ/mol instead of -27 kJ/mol How did you get -12.35 kJ? I used the one for NH3 in the back of the book that was -32.9 kJ/mol since the standard GFE for the reactants are zero. For this question, you also us...
Thu Feb 20, 2020 2:20 pm
Forum: Gibbs Free Energy Concepts and Calculations
Topic: 5G.15
Replies: 5
Views: 89

### Re: 5G.15

For 5G.15, for the standard GFE I got -12.35 kJ and for my final answer, I actually got -2.7 kJ/mol instead of -27 kJ/mol I also got -2.7 kJ/mol, did you happen to figure out what went wrong? Thank you!! I'm not sure I think the book just made an error but I checked with other people and they also ...
Thu Feb 20, 2020 2:20 pm
Forum: Gibbs Free Energy Concepts and Calculations
Topic: 5G. 13
Replies: 6
Views: 128

### Re: 5G. 13

For G, I got -19.124 kJ instead of 19.33 kJ. You would use the equation G = -RTlnK to find what G is. So, you use G=-RTlnK to find the standard GFE and not the ones in the back of the book? Yup! You would use the ones in the back of the book if they didn't give you equilibrium and values to find Q.
Sat Feb 15, 2020 8:17 pm
Forum: Van't Hoff Equation
Topic: Enthalpy, Entropy, and Gibbs Free Energy
Replies: 7
Views: 83

### Enthalpy, Entropy, and Gibbs Free Energy

For the Van't Hoff Equation, if we assume the change in standard entropy and standard enthalpy to be constant, then is the change in standard Gibbs free energy also constant because deltaG = deltaH + TdeltaS?
Sat Feb 15, 2020 8:12 pm
Forum: General Science Questions
Topic: Converting Liters to m^3 ?
Replies: 2
Views: 79

### Re: Converting Liters to m^3 ?

You could also think of it this way, where 1 mL = 1 cm^3 so therefore 1 L = 1000 cm^3 and 1L = 0.001 m^3
Sat Feb 15, 2020 8:07 pm
Forum: Gibbs Free Energy Concepts and Calculations
Topic: Unit for Pressure in delta G equation
Replies: 2
Views: 66

### Re: Unit for Pressure in delta G equation

Yes as long as the two pressures given are the same units then it doesn't matter because when we did chemical equilibrium we also used bars for pressure. So it will continue to be the same here. Hope this helps!
Sat Feb 15, 2020 8:05 pm
Forum: Gibbs Free Energy Concepts and Calculations
Topic: 5G.15
Replies: 5
Views: 89

### Re: 5G.15

For 5G.15, for the standard GFE I got -12.35 kJ and for my final answer, I actually got -2.7 kJ/mol instead of -27 kJ/mol
Sat Feb 15, 2020 8:00 pm
Forum: Gibbs Free Energy Concepts and Calculations
Topic: 5G. 13
Replies: 6
Views: 128

### Re: 5G. 13

For G, I got -19.124 kJ instead of 19.33 kJ. You would use the equation G = -RTlnK to find what G is.
Fri Feb 07, 2020 12:49 am
Forum: Third Law of Thermodynamics (For a Unique Ground State (W=1): S -> 0 as T -> 0) and Calculations Using Boltzmann Equation for Entropy
Topic: 3rd Law of Thermodynamics
Replies: 2
Views: 31

### 3rd Law of Thermodynamics

What is the 3rd Law of Thermodynamics and why is it important? How does it relate to entropy or enthalpy?
Fri Feb 07, 2020 12:38 am
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: molar heat capacity
Replies: 2
Views: 42

### Re: molar heat capacity

The molar heat capacity is given as a specific value for a compound when it is not an ideal gas. When the compound is an ideal gas, depending on whether or not it is mono, linear, and non-linear and whether or it is constant volume or constant pressure there would be different ratios.
Fri Feb 07, 2020 12:34 am
Forum: Entropy Changes Due to Changes in Volume and Temperature
Topic: Entropy and Equations (reversible vs irreversible)
Replies: 2
Views: 26

### Re: Entropy and Equations (reversible vs irreversible)

Since entropy is a state function, it doesn't matter if the reaction is reversible or irreversible. We would just do everything separately.
Fri Feb 07, 2020 12:21 am
Forum: Calculating Work of Expansion
Topic: Isothermal expansion of an ideal gas
Replies: 2
Views: 46

### Re: Isothermal expansion of an ideal gas

Heat energy is still being transferred into or out of the system if work is being done on or by the system because in order for deltaU to be equal to zero then there must be heat energy to balance out the amount of work done for the deltaU = 0 because deltaU = heat energy + work. However, if no work...
Fri Feb 07, 2020 12:15 am
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: Monatomic ideal gases
Replies: 2
Views: 47

### Re: Monatomic ideal gases

You use the ideal gas constant for monoatomic ideal gases when you have constant pressure or constant volume. Some examples of monoatomic ideal gases include all the noble gases on the periodic table, like Xenon, Neon, etc.
Sun Feb 02, 2020 6:40 pm
Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
Topic: Constant Volume and Pressure
Replies: 7
Views: 49

### Re: Constant Volume and Pressure

When you have a constant volume or pressure, it means that the volume and pressure is fixed and won't change during the reaction.
Sun Feb 02, 2020 6:39 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: 4A.13
Replies: 3
Views: 31

### Re: 4A.13

Yes it is because a change in temperature is the same no matter the units and so a change in temperature of 7.32 C is the same as a change in temperature of 7.32 K
Sun Feb 02, 2020 6:34 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: Heat Capacity 4C.3
Replies: 3
Views: 45

### Re: Heat Capacity 4C.3

You would use the equations qp = nCpΔT and qv = nCvΔT to find the final temperature. Make sure to know that Cp = 5/2R and Cv = 3/2R
Sun Feb 02, 2020 6:29 pm
Forum: Calculating Work of Expansion
Topic: Two different equations
Replies: 2
Views: 41

### Re: Two different equations

The first work equation is the one with the integral and you would use that if pressure isn't constant. However, if pressure is constant then you would use w = -P ΔV.
Sun Feb 02, 2020 6:25 pm
Forum: Concepts & Calculations Using First Law of Thermodynamics
Topic: extensive property
Replies: 12
Views: 168

### Re: extensive property

Extensive property is something that depends on the amount of material. For instance, since heat required depends on the amount of substance there is, heat capacity is an extensive property. Other examples of extensive property include volume, mass, weight, and etc.
Sun Feb 02, 2020 12:34 am
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Hess's Law vs Bond Enthalpies vs Standard Enthalpies of Formation
Replies: 7
Views: 67

### Re: Hess's Law vs Bond Enthalpies vs Standard Enthalpies of Formation

You use Hess's Law when you are giving the enthalpy change of the total reaction. You use bond enthalpies when they give you the enthalpy change based on bonds, for example C-H 413KJ/mol. And you use standard enthalpies of formation when they give you the enthalpy of a compound. Hess's Law is for th...
Fri Jan 24, 2020 1:31 am
Forum: Phase Changes & Related Calculations
Topic: Phase Changes
Replies: 3
Views: 51

### Phase Changes

Are there any phase changes from vapor --> liquid, liquid --> solid, or vapor --> solid? Are these changes just the exothermic process of the ones we talked about in class?
Fri Jan 24, 2020 1:25 am
Forum: Equilibrium Constants & Calculating Concentrations
Topic: HNO2(aq) + H2O(l) -> H3O+(aq) + NO2-(aq)
Replies: 2
Views: 42

### Re: HNO2(aq) + H2O(l) -> H3O+(aq) + NO2-(aq)

KNO2 is the salt in the reaction, and as a salt it dissolves into K+ and NO2-. That's why 0.15M KNO2 is assigned to NO2- because KNO2 dissolves into NO2-.
Fri Jan 24, 2020 1:21 am
Forum: Calculating Work of Expansion
Topic: Reversible vs. Irreversible Reactions
Replies: 2
Views: 45

### Re: Reversible vs. Irreversible Reactions

A reversible reaction means that it could occur both ways. Either a forward reaction (reactants --> products) could occur or a reverse reaction (products --> reactants) could occur.
Fri Jan 24, 2020 1:19 am
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: Ka and Kb
Replies: 10
Views: 167

### Re: Ka and Kb

Yes, Ka and Kb are only assigned to weak acids and bases because Ka and Kb are the equilibrium constants for the dissociation of acid or base in the water and if you have a value for Ka and Kb that means that the acid or base isn't fully dissociated yet and not being completely dissociated is relate...
Fri Jan 24, 2020 1:15 am
Forum: Ideal Gases
Topic: Homework 3
Replies: 6
Views: 227

### Re: Homework 3

Yes, it's okay to do problems from Acids and Bases for homework 3 because we just started thermochemistry
Thu Jan 16, 2020 12:42 am
Forum: Acidity & Basicity Constants and The Conjugate Seesaw
Topic: kA and kB
Replies: 3
Views: 121

### kA and kB

The lower pKa and pKb, the stronger the acid and base. Does that mean the higher the kA and kB, the stronger the acid and base? Since, they are inversely related.
Thu Jan 16, 2020 12:37 am
Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
Topic: Approximation
Replies: 6
Views: 160

### Approximation

Why is it that if X is less than 5% of initial then approximation is okay? Like why is the cut off 5%?
Thu Jan 16, 2020 12:30 am
Forum: Equilibrium Constants & Calculating Concentrations
Topic: 6C#9
Replies: 2
Views: 17

### Re: 6C#9

You would look at the pKb values in Tables 6C.2 to determine the strength of the base. The lower the pKb, the stronger the base.
Thu Jan 16, 2020 12:27 am
Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
Topic: 6D.15
Replies: 1
Views: 59

### Re: 6D.15

The dissociation reaction is AlCl3 + H2O --> Al(OH)3 + HCl. H2O would always be added because it is a solvent and then with that you could figure out the products. The equation above is not balanced and then HCl would dissolve into H+ and Cl- and you would use that to calculate the pH.
Thu Jan 16, 2020 12:23 am
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Help on 5.35
Replies: 5
Views: 55

### Re: Help on 5.35

It says in the problem that compound A decomposes into compounds B and C. So the chemical equation would be A (g) --> B (g) + C (g)
Sun Jan 12, 2020 1:30 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Quick way
Replies: 7
Views: 94

### Quick way

Why is the quick way to know whether or not the reaction shifts to the right or left for change in pressure not exactly correct according to Dr. Lavelle?
Sun Jan 12, 2020 1:26 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: K = 1
Replies: 2
Views: 19

### K = 1

Why is K = 1 considered rare to achieve?
Sun Jan 12, 2020 1:23 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: 5I.27
Replies: 6
Views: 43

### Re: 5I.27

Part c is asking for the amount of each product and reactant at equilibrium. So you would use the ICE method to figure out the concentrations of the reactants and products.
Sun Jan 12, 2020 1:18 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Functions
Replies: 2
Views: 42

### Re: Functions

What function you use is determined by the amount of products you have. You have to use the ICE rule to determine the equation and exponents used.
Sun Jan 12, 2020 1:12 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Pure substances in reactions
Replies: 2
Views: 25

### Re: Pure substances in reactions

Yea, there can't be any reactions that only contains pure substances because two solids wouldn't mix together to create another solid as there needs to be a solvent for the reaction to occur. In most cases, the solvent would be H2O and since the concentration amount is insignificant, it is often not...
Sat Dec 07, 2019 2:49 pm
Forum: Naming
Topic: (en), (dien), etc.
Replies: 6
Views: 107

### Re: (en), (dien), etc.

Yes, I'm pretty sure you can use abbreviations.
Sat Dec 07, 2019 2:44 pm
Forum: Student Social/Study Group
Topic: most stable
Replies: 6
Views: 306

### Re: most stable

The most stable form of a Lewis structure is when all the formal charges on the molecules are zero.
Sat Dec 07, 2019 2:41 pm
Forum: Conjugate Acids & Bases
Topic: Strength
Replies: 2
Views: 129

### Re: Strength

No, a strong acid will have a weak conjugate base and it is the same for bases.
Sat Dec 07, 2019 2:32 pm
Forum: Dipole Moments
Topic: summarize dipole dipole moments
Replies: 1
Views: 95

### Re: summarize dipole dipole moments

Yea, everything you said is correct and additionally all polar molecules form dipole-dipole
Sat Dec 07, 2019 2:27 pm
Forum: Biological Examples
Topic: Hemoglobin and Myoglobin
Replies: 2
Views: 53

### Re: Hemoglobin and Myoglobin

Hemoglobin is made out of 4 myoglobin-like molecules. The hemoglobin binds to the 4 O2. While myoglobin is the heme complex + protein and the heme complex is Fe bound to porphyrin ligand.
Sat Nov 30, 2019 2:38 pm
Forum: Properties & Structures of Inorganic & Organic Acids
Topic: Weak Acids & Bases
Replies: 6
Views: 170

### Weak Acids & Bases

What are some examples of weak acids and bases?
Sat Nov 30, 2019 2:31 pm
Forum: Industrial Examples
Topic: What do we need to know?
Replies: 15
Views: 455

### Re: What do we need to know?

No, cisplatin should be all we need to know for industrial examples of coordination compounds. But remember that we also need to know biological examples of coordination compounds.
Sat Nov 30, 2019 2:28 pm
Forum: Naming
Topic: Water
Replies: 1
Views: 41

### Re: Water

You use aqua for water when the ligand has no charge and you use dihydrate when the ligand is either a cation or anion.
Wed Nov 27, 2019 8:33 pm
Forum: Hybridization
Topic: single vs double vs triple bonds
Replies: 4
Views: 86

### Re: single vs double vs triple bonds

The number of bonds don't affect the hybridization because we see double and triple bonds as one region of electron density just like how we did when we determining shape using VSEPR.
Wed Nov 27, 2019 4:51 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Coordinate covalent bonds
Replies: 4
Views: 61

### Re: Coordinate covalent bonds

For coordinate covalent bonds, a lone pair is donated from the atoms, while in an ionic bond, the valence electrons are donated from the atoms. That is the difference between coordinate covalent bonds and ionic bonds.
Sat Nov 23, 2019 9:30 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Coordinate covalent bonds
Replies: 2
Views: 41

### Coordinate covalent bonds

What is the difference between coordinate covalent bonds and covalent bonds? Or is there no difference? But if there is no difference why can't we just call them covalent bonds?
Sat Nov 23, 2019 9:26 pm
Forum: Bronsted Acids & Bases
Topic: Bronsted Acids vs Lewis acids
Replies: 4
Views: 55

### Bronsted Acids vs Lewis acids

What is the difference between bronsted acids and Lewis acids? Why do we need to classify acids differently?
Sat Nov 23, 2019 9:23 pm
Forum: Biological Examples
Topic: Biological Applications to Know
Replies: 3
Views: 121

### Re: Biological Applications to Know

You should also be aware of the function of cisplatin. And other biological applications include the importance of chromium and how it assists insulin in control of blood sugar, cobalt and how it helps with vitamin B12, and how Mn, Ni, Cu, Zn are critical for enzyme function.
Sat Nov 23, 2019 9:18 pm
Forum: Hybridization
Topic: Hybridization Notation
Replies: 5
Views: 95

### Re: Hybridization Notation

Yes, the d comes from the s and p orbital
Sat Nov 23, 2019 9:16 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Polydentate
Replies: 3
Views: 46

### Re: Polydentate

A ligand that is polydentate can form many bonds
Sat Nov 16, 2019 2:49 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 interactions
Replies: 2
Views: 46

### Dipole-dipole interactions

I'm confused about homework question 3F.3. How can you determine when dipole-dipole interactions are important? What does that even mean?
Sat Nov 16, 2019 2:42 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Interaction Potential Energy
Replies: 3
Views: 68

### Re: Interaction Potential Energy

The formula, kq1q2/r, refer to the electric potential energy which finds the potential energy between two charges. While the formula, Dr.Lavelle talked about in class refers to the interaction potential energy which finds the potential energy between two atoms.
Fri Nov 15, 2019 12:17 am
Forum: Determining Molecular Shape (VSEPR)
Topic: Other shapes
Replies: 3
Views: 36

### Re: Other shapes

It might be mentioned during lecture tomorrow. I heard from my TA that the lecture tomorrow would still be included on the test
Thu Nov 14, 2019 4:19 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: 2.27
Replies: 1
Views: 30

### Re: 2.27

For b, a radical is a lewis structure that has an unpaired electron. So when you draw the Lewis structure and you find that you have one unpaired electron, which is usually on the central atom, then it is on a radical. Then for the increasing HCH bond angles you would have to do VSEPR theory to figu...
Thu Nov 14, 2019 3:57 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Test 2
Replies: 11
Views: 173

### Re: Test 2

My TA said that test 2 would be everything that was not on midterm up to what we learn in class on Friday. So, things such as like dipole-dipole, intermolecular forces, and VSEPR theory.
Thu Nov 14, 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: 3F.13
Replies: 2
Views: 66

### Re: 3F.13

First, you would try to figure out what atoms correspond to which color. So looking at the diagram, the dark grey atom would be carbon because it is the central atom. Then, the light grey atom would be hydrogen because hydrogen is smaller than chlorine. So then that leaves the green atom to be chlor...
Sat Nov 09, 2019 8:37 pm
Forum: Dipole Moments
Topic: Interaction potential energy
Replies: 1
Views: 54

### Interaction potential energy

Why is the interaction potential energy always negative? What makes the interaction potential energy negative?
Sat Nov 09, 2019 8:32 pm
Forum: Bond Lengths & Energies
Topic: Bond Shape
Replies: 3
Views: 123

### Re: Bond Shape

Molecules are polar when electrons are not equally shared and that means that there is a big difference in electronegativity between the two molecules, making one molecule more negative and the other more positive. Below, I have attached a picture showing H2O being polar. http://upload.wikimedia.org...
Sat Nov 09, 2019 8:27 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: 11/8/19 Friday Lecture
Replies: 1
Views: 36

### Re: 11/8/19 Friday Lecture

No, we won't be tested on the shapes of pentane and dimethylpropane. We just need to know that the rod-shaped molecules are closer together and therefore they are stronger than a spherical-shaped molecule.
Sat Nov 09, 2019 8:25 pm
Forum: Bond Lengths & Energies
Topic: Bonds
Replies: 2
Views: 70

### Re: Bonds

Hydrogen and covalent bonds are different things because hydrogen bonds are between molecules, while covalent bonds are between atoms. Hydrogen bonds are intermolecular forces, while covalent bonds are intramolecular forces. So we can't really compare the two for bond strength and length
Sat Nov 09, 2019 6:50 pm
Forum: Bond Lengths & Energies
Topic: Hydrogen Bonding melting point
Replies: 3
Views: 59

### Re: Hydrogen Bonding melting point

Hydrogen Bonding explains a higher melting point because they are a very strong intermolecular force, which means that more energy is needed to break the bond leading to a higher melting point.
Sat Nov 02, 2019 12:10 am
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: making change in energy negative
Replies: 2
Views: 39

### Re: making change in energy negative

You also make the change in energy negative because we can't have a negative energy of a photon. So instead, we make the change in energy negative.
Sat Nov 02, 2019 12:07 am
Forum: Trends in The Periodic Table
Topic: Ionization Energy (10d on Midterm Review)
Replies: 3
Views: 46

### Re: Ionization Energy (10d on Midterm Review)

No, you don't always have to write out the full electron configuration because you just have to know the periodic trend for ionization energy, which is that it increases from bottom to top and left to right. As for the exceptions we need to know, they are oxygen and nitrogen, where nitrogen is great...
Fri Nov 01, 2019 11:59 pm
Forum: Bond Lengths & Energies
Topic: Bond strength and electronegativity
Replies: 2
Views: 62

### Re: Bond strength and electronegativity

The electronegativity is the e- pulling power of an atom. So, the stronger the e- pulling power of an atom, the electronegativity, the stronger the bond strength.
Fri Nov 01, 2019 11:54 pm
Forum: *Shrodinger Equation
Topic: ?
Replies: 2
Views: 175

### Re: ?

The Schrodinger's wave function equation is to show that there are many solutions, which means that there are many different orbitals. I think that's all you need to know about it.
Fri Nov 01, 2019 10:47 pm
Forum: Lewis Structures
Topic: Compound Names
Replies: 3
Views: 54

### Re: Compound Names

You would most likely get the formula, so you wouldn't have to just know the name. But in a situation, where you would have to know the name, you would start by looking at the periodic table for the charges or you have to remember the polyatomic ions.
Fri Oct 25, 2019 2:39 pm
Forum: Ionic & Covalent Bonds
Topic: Identifying Ionic vs Covalent
Replies: 7
Views: 90

### Re: Identifying Ionic vs Covalent

You can identify that a bond is ionic because electrons are being transferred from metal to nonmetal atoms, while a bond is covalent because electrons are being shared instead of being transferred.
Fri Oct 25, 2019 2:32 pm
Forum: Lewis Structures
Topic: Drawing Lewis Structures
Replies: 8
Views: 103

### Drawing Lewis Structures

Is there ever an exception where you won't choose the atom with the lowest ionization energy as the central atom?
Fri Oct 25, 2019 2:29 pm
Forum: Properties of Electrons
Topic: Mass of electron in 1B.15
Replies: 3
Views: 53

### Re: Mass of electron in 1B.15

No, we weren't suppose to know the mass of electron. You can look it up. We would be provided this information on the test.
Fri Oct 25, 2019 2:26 pm
Forum: Lewis Structures
Topic: Charges on atoms with lower e- affinity
Replies: 4
Views: 48

### Re: Charges on atoms with lower e- affinity

Dr. Lavelle was saying that you shouldn't put more charges on a lower electron affinity molecule because that would make the whole lewis structure less stable, which is what you don't want.
Fri Oct 25, 2019 2:21 pm
Forum: Resonance Structures
Topic: Resonance
Replies: 3
Views: 100

### Re: Resonance

The bond energy is lower because it is no longer just double bonds, but rather a mixture between double bonds and single bonds, so the energy would would be lower.
Fri Oct 18, 2019 2:24 am
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: Spin Magnetic Quantum #
Replies: 6
Views: 276

### Spin Magnetic Quantum #

Why is the spin magnetic quantum number only either +1/2 or -1/2? Was this found through experiments? Is it possible for it to be any other number?
Fri Oct 18, 2019 2:22 am
Forum: DeBroglie Equation
Topic: 1A13
Replies: 1
Views: 27

### Re: 1A13

For a, you would use the Rydberg equation to find frequency, v. The Rydberg equation would be v = R((1/(n1)^2) - (1/(n2)^2), with R = 3.29x10^15 Hz. After finding the frequency, you would use the c = λv to find wavelength. For b, you would look at the wavelength you got in part a and then look at th...
Fri Oct 18, 2019 2:15 am
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: Orbitals in relation to arrows
Replies: 10
Views: 249

### Re: Orbitals in relation to arrows

The arrows that he draws in class is called the spin magnetic quantum number and they are telling us which way the electrons in the orbitals are spinning, which is either up and down. As for how you would determine whether or not the arrows are spinning up or down there will always be spin up and sp...
Fri Oct 18, 2019 2:07 am
Forum: Properties of Light
Topic: Constants and equations
Replies: 4
Views: 54

### Re: Constants and equations

No, we would be giving an equations and constants sheet. It should be the first page of the test.
Fri Oct 18, 2019 2:06 am
Forum: *Particle in a Box
Topic: Particle in a box
Replies: 1
Views: 153

### Re: Particle in a box

A particle in a box has zero potential energy inside the box because it has kinetic energy. Since, the particle is inside the box it's constantly moving around because it keep hitting the walls/sides of the box giving it kinetic energy and since it has kinetic energy it would have zero potential ene...
Thu Oct 10, 2019 9:47 pm
Forum: Photoelectric Effect
Topic: Photons and electrons
Replies: 5
Views: 115

### Photons and electrons

I was wondering how do you know the right wavelength to have the electrons ejected. How do we figure out the right wavelength? Is there an equation for that?
Thu Oct 10, 2019 9:42 pm
Forum: Photoelectric Effect
Topic: Photoelectric Effect
Replies: 3
Views: 78

### Photoelectric Effect

I'm still confused on the difference between the photoelectric effect and atomic spectra. I know that for both a higher frequency is better as there is more energy to eject the electron. So, what is the difference? Is it just the way the experiments are conducted?
Thu Oct 10, 2019 9:38 pm
Forum: Einstein Equation
Topic: Energy of photons to Moles
Replies: 2
Views: 96

### Re: Energy of photons to Moles

You would use the equations E=hv and c=λv to first find the energy of the photon and then you would multiply the energy of the photon by Avogadro's number.