Search found 99 matches

Wed Mar 11, 2020 12:32 pm
Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
Topic: Concentration
Replies: 9
Views: 69

Re: Concentration

They way you'd figure out if the anode or the cathode was in the numerator is by looking at the overall reaction. Products are always in the numerator and reactants are in the denominator.
Wed Mar 11, 2020 12:30 pm
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: 117

Re: E cell

Yes, the E standard value implies standard state conditions and in a concentration cell, the reaction is at equilibrium.
Wed Mar 11, 2020 12:15 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Work max
Replies: 4
Views: 87

Re: Work max

Yes the Gibbs Free Energy all the available energy, and if Wmax = G, then no free energy is not being contributed toward work.
Wed Mar 11, 2020 12:14 pm
Forum: Balancing Redox Reactions
Topic: Balancing a reaction
Replies: 5
Views: 50

Re: Balancing a reaction

You can balance O and H by adding water and protons in the case of an acidic solution, or OH- in the case of a basic solution.
Wed Mar 11, 2020 12:13 pm
Forum: Balancing Redox Reactions
Topic: Balancing basic reactions
Replies: 8
Views: 80

Re: Balancing basic reactions

As long as the charges and number of atoms are balanced, meaning that the number of atoms on one side equals the number of atoms on the other, the equations are balanced. OH- is only added in cases where the reaction takes place in a basic solution.
Wed Mar 11, 2020 12:11 pm
Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
Topic: How to determine Q
Replies: 4
Views: 64

Re: How to determine Q

Yes by writing the reactions, you can figure out the products and reactants and put them in the equation.
Wed Mar 11, 2020 12:07 pm
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: Work and Delta G
Replies: 4
Views: 35

Re: Work and Delta G

Gibbs free energy represents all the energy available to do work, so wmax would mean that all the energy is being used for work.
Wed Mar 11, 2020 11:44 am
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Adding carbon (gr) to cell diagrams
Replies: 4
Views: 50

Re: Adding carbon (gr) to cell diagrams

Both graphite and platinum are inert conductors that must be used when you have two of the same species and phase or a gas-ion reaction. They are both interchangeable.
Wed Mar 11, 2020 11:42 am
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: Combustion of gas
Replies: 6
Views: 132

Re: Combustion of gas

The way you can be completely sure that the reaction is spontaneous is by looking at the equation: G = H - TS. Because H will most likely be negative and S will be positive, combustion usually is spontaneous.
Wed Mar 11, 2020 11:40 am
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: E potential
Replies: 8
Views: 79

Re: E potential

Yes, because the E value represents the reduction potential, flipping it represents the oxidation potential. The higher reduction potential will be the cathode, while the flipped oxidation reaction will be the anode.
Wed Mar 11, 2020 11:35 am
Forum: Balancing Redox Reactions
Topic: Determining the oxidizer and reducer
Replies: 10
Views: 92

Re: Determining the oxidizer and reducer

A key concept to understand is that an oxidizing agent is more likely to be reduced while a reducing agent is more likely to be oxidized.
Wed Mar 11, 2020 11:34 am
Forum: Balancing Redox Reactions
Topic: 6K.3 part D
Replies: 3
Views: 49

Re: 6K.3 part D

Yes in this reaction, 2Cl is losing electrons as is normal for any oxidation reaction.
Wed Mar 11, 2020 11:33 am
Forum: Balancing Redox Reactions
Topic: balancing reactions
Replies: 6
Views: 38

Re: balancing reactions

The end goal of balancing half reactions is that the charge and number of atoms on one side of the reactions equals the charge and number of atoms on the other side. This can be done by adding H+, H2O, and electrons to, or in the case of a reaction taking place in base, you can add OH-.
Tue Mar 10, 2020 3:44 pm
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: Problem 6N.1 part b
Replies: 4
Views: 97

Re: Problem 6N.1 part b

You can find n by balancing the half reactions in a given redox reaction. Because the amount of electrons transferred in oxidation equals the amount transferred in reduction, you can find a single value for n, the number of moles of electrons transferred in total.
Tue Mar 10, 2020 3:29 pm
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: Finding k1 when given two temperatues
Replies: 6
Views: 110

Re: Finding k1 when given two temperatues

Yes, it does not really matter which one is T1 and which one is T2, as long as they're correctly matched with their respective K values.
Tue Mar 10, 2020 3:15 pm
Forum: Balancing Redox Reactions
Topic: Half Reactions
Replies: 15
Views: 130

Re: Half Reactions

Yes, you can treat balancing half reactions as if they are in acid at first in order to balance the number of electrons and negative charges on one side with protons on the other. The only difference is that for a basic solution, you have to add OH- to balance out the H+.
Mon Mar 09, 2020 9:00 pm
Forum: Interesting Applications: Rechargeable Batteries (Cell Phones, Notebooks, Cars), Fuel Cells (Space Shuttle), Photovoltaic Cells (Solar Panels), Electrolysis, Rust
Topic: pH
Replies: 3
Views: 60

Re: pH

By finding Q, you can find the concentration of H+. pH is then defined as the -log[H+].
Mon Mar 09, 2020 8:57 pm
Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
Topic: 6l.1
Replies: 2
Views: 38

Re: 6l.1

n is the number of moles of electrons transferred during a reaction. Because the amount of electrons transferred in oxidation must equal the number of moles of electrons transferred during reduction, you can find n by balancing the half reactions.
Mon Mar 09, 2020 8:55 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: 6M.11
Replies: 4
Views: 103

Re: 6M.11

Yes, often by losing charge and converting to the solid phase, you can see the accumulation of the solid metal on the electron. The charge ion is usually able to dissolve in the water.
Mon Mar 09, 2020 8:52 pm
Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
Topic: Cathode and Anode K
Replies: 2
Views: 53

Re: Cathode and Anode K

You can use the final E value as compared to the standard E value in order to solve for Q. Thus once you have Q and the concentration of either the product or reactant, you can use that to find the concentration of the other concentration value.
Mon Mar 09, 2020 8:48 pm
Forum: Balancing Redox Reactions
Topic: Balancing redox with h2o
Replies: 9
Views: 123

Re: Balancing redox with h2o

Yes, you can start by using H+ to balance out the electrons and negative charges on one side. If it is basic, then you have to add OH- to neutralize the H+, and make sure that the charges and atoms on one side of the reaction match the charge and atoms on the other side.
Mon Mar 09, 2020 8:46 pm
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: Units for n
Replies: 5
Views: 62

Re: Units for n

You can find out the number of moles of electrons being transferred by balancing the half reactions. The number of moles of electrons involved in oxidation should equal the amount involved in reduction.
Sun Mar 08, 2020 5:17 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Cell Diagrams
Replies: 7
Views: 49

Re: Cell Diagrams

A cell diagram is just shorthand notation for the overall reaction that occurs in a cell. Because stochiometric coefficients can easily be determined from this shorthand notation, it is not necessary for them to just be included.
Sun Mar 08, 2020 5:16 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Cell Diagrams
Replies: 7
Views: 49

Re: Cell Diagrams

Either platinum or graphite can be used as an inert conductor for most reactions in which they are needed.
Sun Mar 08, 2020 5:13 pm
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: Reduced/Oxidized based on Ecell
Replies: 6
Views: 114

Re: Reduced/Oxidized based on Ecell

Yes, if there is a difference in concentrations or other factors, then this will contribute to which species is oxidized/reduced.
Sun Mar 08, 2020 5:06 pm
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: 6M.5 c)
Replies: 3
Views: 34

Re: 6M.5 c)

Yes, because H2O is mainly an inert, excess factor in this reaction, it is not important to include it in the cell diagram.
Sun Mar 08, 2020 5:05 pm
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: K
Replies: 5
Views: 70

Re: K

If Ecell is positive, this means that the redox reaction that favors products are positive. At standard conditions at equilibrium, this would mean K is positive. If equilibrium has not yet been achieved, this means that Q is positive.
Sun Mar 08, 2020 5:03 pm
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: finding moles
Replies: 6
Views: 136

Re: finding moles

Because your half reactions need to have the same amount of electrons be transferred in either reduction or oxidation, there will be a single number of moles transferred in the overall balanced redox reaction.
Sun Mar 08, 2020 5:01 pm
Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
Topic: concentration cells
Replies: 4
Views: 61

Re: concentration cells

Yes, in a concentration cell, the species that experiences oxidation or reduction is the same. Which site is the cathode or the anode depends on the concentration of their respective solutions.
Sun Mar 08, 2020 4:59 pm
Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
Topic: Writing reaction equations for concentration cells
Replies: 3
Views: 40

Re: Writing reaction equations for concentration cells

Also, the cathode is the site in which reduction takes place, and the anode is the electrode in which oxidation takes place.
Sun Mar 08, 2020 4:57 pm
Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
Topic: Using partial pressure in Q
Replies: 6
Views: 67

Re: Using partial pressure in Q

Yes, Q and K can both be calculated either in terms of partial pressures of concentrations depending on the context of the problem.
Sun Mar 08, 2020 4:56 pm
Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
Topic: Changes in Q
Replies: 3
Views: 79

Re: Changes in Q

Yes, by looking at the Nernst equation, you can see that mass is never factored into the final calculation, while concentration definitely is. As such, diluting the solution will change the final answer you obtain, but changing the mass of the electrode will not.
Sun Mar 08, 2020 4:55 pm
Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
Topic: HW 6.63
Replies: 2
Views: 71

Re: HW 6.63

Yes, because n refers to the moles of electrons transferred, when we know that borate is the key species being involved in the redox reaction and that it usually only transfers one electron, we know that n equals one.
Sun Mar 08, 2020 4:53 pm
Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
Topic: Cell potentials and concentration
Replies: 3
Views: 46

Re: Cell potentials and concentration

Yes, and until your solution reaches equilibrium and Q = 1 (which means that ln Q = 0), your E will always be changing until it find equals E(standard).
Sun Mar 08, 2020 4:52 pm
Forum: Balancing Redox Reactions
Topic: Both Oxidizing and Reducing Agent
Replies: 4
Views: 66

Re: Both Oxidizing and Reducing Agent

Yes, typically reducing agents are more likely to be oxidized, and oxidizing agents are more likely to be reduced.
Sun Mar 08, 2020 4:49 pm
Forum: Balancing Redox Reactions
Topic: Oxidation number
Replies: 5
Views: 59

Re: Oxidation number

You can think of the oxidation number as the charge that an atom would have it were to be in a completely ionic bond with the species that is currently covalently bonded to. For example in H2O, the oxygen would grab an electron from each hydrogen and have an oxidation state of -2, because of the ext...
Sun Mar 08, 2020 4:47 pm
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: Problem 6L.3
Replies: 2
Views: 37

Re: Problem 6L.3

You can also look at the reduction potentials to figure out what species is oxidized and which is reduced.
Sun Mar 08, 2020 4:45 pm
Forum: Balancing Redox Reactions
Topic: Oxidation and Reduction of Carbon and Cromium
Replies: 2
Views: 42

Re: Oxidation and Reduction of Carbon and Cromium

The oxidation states can be thought of as the charges that each individual atom would have if it were to be in a completely ionic bond. This usually changes from reactants to products during the course of a redox reaction. The amount of electrons lost has to equal the amount of electrons gained in a...
Sun Mar 08, 2020 4:43 pm
Forum: Balancing Redox Reactions
Topic: 6K.5 part d
Replies: 3
Views: 71

Re: 6K.5 part d

Also, depending on whether the reaction is happening in base or acid, you may need to add either protons or hydroxide ions.
Thu Jan 30, 2020 10:07 am
Forum: Calculating Work of Expansion
Topic: reversible and irreversible
Replies: 2
Views: 17

Re: reversible and irreversible

A reversible process is one that can be reversed by an infinitely small change in a variable. Irreversible expansion would violate this definition. External pressure is present in both cases.
Thu Jan 23, 2020 12:36 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Halogens
Replies: 2
Views: 58

Re: Halogens

Yes, typically halogens can be ignored when looking at acid-base reactions.
Thu Jan 23, 2020 12:35 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Polyprotic Acids
Replies: 6
Views: 98

Re: Polyprotic Acids

As the acid loses a proton and then another proton, the k values for each step are different.
Thu Jan 23, 2020 12:34 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: 6D.5
Replies: 2
Views: 47

Re: 6D.5

Yes the instructions for this section of problems tell you to look at their tables for equilibrium values.
Thu Jan 23, 2020 12:33 pm
Forum: Ideal Gases
Topic: Partial Pressure
Replies: 4
Views: 63

Re: Partial Pressure

Although the ideal gas equation isn't completely right for modeling gases in the real world it is useful for introductory chemistry.
Thu Jan 23, 2020 12:31 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: 6B.3
Replies: 2
Views: 19

Re: 6B.3

For 6B.3 you have to find out the concentration of hydronium ions and use that to find the pH.
Thu Jan 16, 2020 12:47 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Help on 5.35
Replies: 5
Views: 49

Re: Help on 5.35

You can then use the partial pressures given by the graph along with the reaction A (g) --> B (g) + C (g) to calculate the equilibrium constant.
Thu Jan 16, 2020 12:46 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Autoprolysis
Replies: 9
Views: 125

Re: Autoprolysis

Amphiprotic is specific to the donation and accepting of protons specifically.
Thu Jan 16, 2020 12:45 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: 6A 21
Replies: 2
Views: 36

Re: 6A 21

In water the ratio of hydronium and hydroxide should be equal and that is why it has a pH of 7.
Thu Jan 16, 2020 12:44 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: K units
Replies: 10
Views: 104

Re: K units

K is simply a ratio not a unit of measure
Thu Jan 16, 2020 12:41 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Inert Gas
Replies: 5
Views: 57

Re: Inert Gas

An inert will never affect any part of a chemical reaction.
Thu Dec 05, 2019 3:52 pm
Forum: Bond Lengths & Energies
Topic: Interaction Potential Energy and Radius
Replies: 2
Views: 106

Re: Interaction Potential Energy and Radius

Although polarizability is a factor in determining potential energy, the distance between molecules is much more important due to that value being to the power of 6.
Thu Dec 05, 2019 3:48 pm
Forum: Electronegativity
Topic: Electronegativity
Replies: 2
Views: 132

Re: Electronegativity

Electronegativity is the value of how badly an atom attracts electrons. As such, any atom which wants more electrons to fill its valence shell will be more electronegative. You can use periodic trends to determine electronegativity.
Thu Dec 05, 2019 3:44 pm
Forum: Hybridization
Topic: e geometry and hybridization
Replies: 2
Views: 36

Re: e geometry and hybridization

Yes the number of electron clouds, or the steric number, is used to determine the type of hybrid orbitals that the atom has.
Thu Dec 05, 2019 3:43 pm
Forum: Hybridization
Topic: hybridization
Replies: 3
Views: 46

Re: hybridization

These hybridized orbitals have a certain proportion of s-character, p-character, and/or d-character. For example sp2 is 33% s-character and 66% p-character.
Thu Dec 05, 2019 3:39 pm
Forum: Hybridization
Topic: Counting Charge Clouds
Replies: 2
Views: 40

Re: Counting Charge Clouds

Yes, this is very important. The number of bonds or whether or not it's a lone pair makes no difference.
Thu Dec 05, 2019 3:38 pm
Forum: Hybridization
Topic: Hybridization & Sigma and Pi Bonds
Replies: 4
Views: 59

Re: Hybridization & Sigma and Pi Bonds

These lobes are often parallel to each other unlike sigma bonds which overlap directly.
Thu Dec 05, 2019 3:30 pm
Forum: Hybridization
Topic: steric number
Replies: 2
Views: 51

Re: steric number

The steric number is the number of bonds to the central atom plus the number of lone pairs it has. Essentially it's the number of regions of electron density that the central atom has.
Thu Dec 05, 2019 3:28 pm
Forum: Hybridization
Topic: hybridization
Replies: 3
Views: 74

Re: hybridization

Yes the main purpose of hybridization is that it better explains how atoms bond, which would imply that it mostly happens with outermost orbitals.
Thu Dec 05, 2019 3:26 pm
Forum: Hybridization
Topic: Terminal Atoms
Replies: 2
Views: 45

Re: Terminal Atoms

Especially for VSEPR, we only really have to be concerned about the central atom.
Thu Dec 05, 2019 3:26 pm
Forum: Hybridization
Topic: hybrid orbitals
Replies: 2
Views: 49

Re: hybrid orbitals

Yes the positive or negative nature of the wave function most likely won't be necessary for 14A.
Thu Dec 05, 2019 3:25 pm
Forum: Hybridization
Topic: Hybridized orbitals
Replies: 2
Views: 42

Re: Hybridized orbitals

sp2's energy level is between that of 2s and 2p, so yes the energy level would be implied.
Thu Dec 05, 2019 3:24 pm
Forum: Hybridization
Topic: S Character
Replies: 4
Views: 49

Re: S Character

More s-character means that the shape of the orbital would be more similar to the shape of a normal s-orbital.
Thu Dec 05, 2019 3:23 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Bond Angle of Single Electron of A Free Radical
Replies: 4
Views: 249

Re: Bond Angle of Single Electron of A Free Radical

Yes, one electron would mean less repulsion due to less of a charge.
Thu Dec 05, 2019 3:21 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Square Planar Polarity
Replies: 2
Views: 84

Re: Square Planar Polarity

Yes, if one of those atoms was significantly different in electronegativity, the molecule would be polar.
Thu Dec 05, 2019 3:19 pm
Forum: DeBroglie Equation
Topic: Early quantum
Replies: 2
Views: 116

Re: Early quantum

Doing the homework questions in Chapter 1 might help with preparing for the final.
Sun Nov 17, 2019 6:30 pm
Forum: Dipole Moments
Topic: Ion-dipole molecular force
Replies: 3
Views: 48

Re: Ion-dipole molecular force

It's important that the neutral atom is polar such as in water.
Sun Nov 17, 2019 6:29 pm
Forum: Dipole Moments
Topic: Interaction Potential Energy
Replies: 2
Views: 50

Re: Interaction Potential Energy

The equation is -(α1 * α2) / r^6. The most important thing to remember is that the force is proportional to the distance to the power of 6.
Fri Nov 15, 2019 4:31 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: VSEPR and Lewis Structures
Replies: 2
Views: 33

Re: VSEPR and Lewis Structures

No, Lewis structures do not have to be drawn according to the VSEPR model. Dr. Lavelle said this was the case in class.
Fri Nov 15, 2019 4:30 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: Dipole-induced dipole bond
Replies: 5
Views: 52

Re: Dipole-induced dipole bond

Yes, typically this is the accepted value for nonpolar interactions. However, a molecule can still be nonpolar if the difference in electronegativity is greater than 0.4 but the polarity is symmetrical. This can be seen in molecules such as carbon dioxide.
Fri Nov 15, 2019 4:29 pm
Forum: Hybridization
Topic: Hybridization
Replies: 3
Views: 64

Re: Hybridization

Hybridization is when atomic orbitals are mixed into hybrid orbitals so that chemical bonding is easier. Basically, electrons can move into new hybrid orbitals and these orbitals are used to create bonds with other hybrid orbitals in different atoms in order to for a molecule.
Thu Nov 07, 2019 4:24 pm
Forum: Ionic & Covalent Bonds
Topic: Strength of covalent bonds (2d.3)
Replies: 3
Views: 56

Re: Strength of covalent bonds (2d.3)

You can look up something called the Pauling Scale. Basically this assigns elements a value for electronegativity.
Thu Nov 07, 2019 4:22 pm
Forum: Lewis Structures
Topic: Line Drawings Outline 3
Replies: 2
Views: 48

Re: Line Drawings Outline 3

Yes I think being able to understand and interpret line drawings is important, but I'm not sure if this will ever be tested.
Thu Nov 07, 2019 4:21 pm
Forum: Lewis Structures
Topic: Lewis Dot Structures
Replies: 4
Views: 53

Re: Lewis Dot Structures

I think that the four electrons could be represented as two lone pairs and thus would be present on both sides of the atom.
Thu Nov 07, 2019 4:18 pm
Forum: Lewis Structures
Topic: Expanded Octet
Replies: 4
Views: 82

Re: Expanded Octet

It is important to note that expanded octets only form for elements in period 3 and beyond.
Thu Nov 07, 2019 4:15 pm
Forum: Lewis Structures
Topic: Octet rule exceptions?
Replies: 4
Views: 77

Re: Octet rule exceptions?

Expanded octets are usually only possible for elements in period 3 or beyond.
Thu Nov 07, 2019 4:14 pm
Forum: Lewis Structures
Topic: Exceptions for the octet rule
Replies: 5
Views: 100

Re: Exceptions for the octet rule

Also the first four elements can be seen as exceptions to the octet rule as they can be happy with either just a filled 1s shell, or in the case of hydrogen, it can just have no electrons.
Thu Nov 07, 2019 4:09 pm
Forum: Lewis Structures
Topic: Favorable Bonds
Replies: 5
Views: 75

Re: Favorable Bonds

The number of bonds these atoms actually have is also dependent on what other atom it's bonding with.
Thu Nov 07, 2019 4:08 pm
Forum: Lewis Structures
Topic: Lewis Structure HClO3
Replies: 2
Views: 53

Re: Lewis Structure HClO3

The book also says that in all oxoacids, the hydrogen involved has to have a single bond with an oxygen.
Thu Nov 07, 2019 4:07 pm
Forum: Lewis Structures
Topic: 2.7 Lewis structure for N5 +
Replies: 3
Views: 55

Re: 2.7 Lewis structure for N5 +

N5+ is shaped sort of like a V. The N in the middle has single bond attachments to two other N's and those each have a triple bond connection to another N.
Thu Nov 07, 2019 4:05 pm
Forum: Electronegativity
Topic: 2D 3 and 5
Replies: 2
Views: 58

Re: 2D 3 and 5

Yes, the EN chart shouldn't necessarily be needed when differences in electronegativity are so apparent.
Tue Oct 29, 2019 2:49 pm
Forum: Ionic & Covalent Bonds
Topic: Polarity
Replies: 6
Views: 57

Re: Polarity

You can use the Pauling scale to determine polarity as well.
Tue Oct 29, 2019 2:48 pm
Forum: Ionic & Covalent Bonds
Topic: HW 2A.23
Replies: 2
Views: 32

Re: HW 2A.23

No, if Aluminum gains 3 electrons, it would have a full octet. This leads to the formula for aluminum hydride: AlH3.
Tue Oct 29, 2019 2:44 pm
Forum: Electronegativity
Topic: Polarity
Replies: 5
Views: 63

Re: Polarity

Using the Pauling Scale, a difference of over 0.5 in electronegativity usually means that the molecule is polar. A difference of over 1.7 means that the bond is ionic.
Tue Oct 29, 2019 2:43 pm
Forum: Ionic & Covalent Bonds
Topic: Homework Question 2C3
Replies: 2
Views: 53

Re: Homework Question 2C3

The nomenclature section was highly recommended as reading, and it might be useful just to skim it at least once. I don't think we'll ever be tested on it however.
Tue Oct 29, 2019 2:42 pm
Forum: Lewis Structures
Topic: Exceptions to the Octet Rule
Replies: 3
Views: 48

Re: Exceptions to the Octet Rule

In addition, the first four elements (H, He, Li, and Be) are usually exceptions to the octet rule because there are only 2 electrons is the first subshell.
Tue Oct 22, 2019 12:10 pm
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: Spin Magnetic Quantum #
Replies: 6
Views: 226

Re: Spin Magnetic Quantum #

While we can say that an electron spins "up" or "down," that is actually arbitrary. In reality, electron spin is more complicated than just spinning in one direction or another.
Tue Oct 22, 2019 12:09 pm
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: 1D. Quantum Numbers and Orbitals
Replies: 2
Views: 64

Re: 1D. Quantum Numbers and Orbitals

No, learning the exact shape and being able to draw it completely is not necessary. However, being familiar with what is going on in terms of the orbitals is important.
Tue Oct 22, 2019 12:03 pm
Forum: Quantum Numbers and The H-Atom
Topic: Quantum Numbers
Replies: 7
Views: 110

Re: Quantum Numbers

The spin number is usually either +1/2 or -1/2, denoting whether the electron is "spin-up" or "spin-down." Electrons spinning in different directions are often paired together in a subshell.
Tue Oct 22, 2019 12:02 pm
Forum: Quantum Numbers and The H-Atom
Topic: Electrostatic potential energy
Replies: 3
Views: 45

Re: Electrostatic potential energy

q1 and q2 are usually measured in coulombs which are a unit of energy. r is simply a distance so it can be measured in something like meters.
Tue Oct 22, 2019 12:01 pm
Forum: Quantum Numbers and The H-Atom
Topic: Orbital orders
Replies: 2
Views: 58

Re: Orbital orders

Typically, when electrons are in the ground-state, the lower orbitals are filled first. As there are more electrons, then the p, d, and f orbitals are filled.
Sun Oct 13, 2019 9:52 pm
Forum: Properties of Electrons
Topic: E(photon) equation help
Replies: 2
Views: 41

Re: E(photon) equation help

Yes, you can change KJ/mol to J/mol by multiplying the value (150.6 kJ/mol) by 1000.
Sun Oct 13, 2019 9:50 pm
Forum: Properties of Electrons
Topic: kinetic energy help
Replies: 1
Views: 38

Re: kinetic energy help

You can start by using E = hc/lambda to find the energy of the photon. From there use E (photon) = E (threshold) + KE to find the maximum kinetic energy of the emitted electrons.
Sun Oct 13, 2019 9:45 pm
Forum: Properties of Light
Topic: photoelectric effect
Replies: 3
Views: 56

Re: photoelectric effect

I think D does not describe the photoelectric effect because it instead just describes light going through a medium.
Sun Oct 13, 2019 9:43 pm
Forum: Properties of Light
Topic: 1B #5
Replies: 1
Views: 29

Re: 1B #5

Yes, the constant h-bar should be provided on tests.
Sun Oct 13, 2019 9:41 pm
Forum: Properties of Light
Topic: How to start on 1B.9
Replies: 1
Views: 38

Re: How to start on 1B.9

You can start by using the equation E = hc / lambda. Solve for E and use that to find the number of photons.
Sun Oct 13, 2019 4:48 pm
Forum: DeBroglie Equation
Topic: P
Replies: 3
Views: 82

Re: P

Yes, p represent momentum and is equivalent can be found by multiplying mass and velocity together getting units of kilogram meter per second.
Sun Oct 13, 2019 4:43 pm
Forum: Properties of Electrons
Topic: electron energy
Replies: 4
Views: 56

Re: electron energy

There is a certain amount of energy needed for an electron to leave a stable state. This is known as the ionization energy. This value may vary depending on the properties of whatever is being looked at.
Sun Oct 13, 2019 4:39 pm
Forum: Properties of Light
Topic: Wave-Particle Behavior
Replies: 4
Views: 77

Re: Wave-Particle Behavior

The photoelectric effect is an example of the particle behavior view of electromagnetic radiation, while the double slit experiment supports the wave view.
Sun Oct 13, 2019 4:37 pm
Forum: Properties of Light
Topic: Photoelectric vs. Atomic spectra
Replies: 4
Views: 51

Re: Photoelectric vs. Atomic spectra

Hello, I think that the main difference between the photoelectric effect and atomic spectroscopy is that the photoelectric effect describes the phenomenon of electron emission due to the absorption of photons. Atomic spectroscopy instead refers to the emission of photons after the relaxation of elec...

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