Search found 98 matches

by Dominic Benna 2E
Thu Mar 04, 2021 8:41 pm
Forum: Balancing Redox Reactions
Topic: Oxidation and Reduction
Replies: 10
Views: 34

Re: Oxidation and Reduction

A compound cannot be oxidizing and reducing at the same time. This confusion may come from the fact that a compound that is oxidized is the reducing agent and a compound that is reduced is the oxidizing agent.
by Dominic Benna 2E
Thu Mar 04, 2021 8:39 pm
Forum: Concepts & Calculations Using Second Law of Thermodynamics
Topic: qrev
Replies: 27
Views: 111

Re: qrev

qrev is the amount of heat that can be produced (or lost) in a reversible process. So it is saying in this equation it is not asking for the heat produced or lost by an irreversible reaction.
by Dominic Benna 2E
Thu Mar 04, 2021 8:37 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: Isolated System
Replies: 14
Views: 29

Re: Isolated System

Even when a system cannot exchange energy or substances with the surroundings it can still have internal changes. For example a bomb calorimeter can have a reaction within it that changes the two substances or two substances can be in an isolated system at different temperatures and exchange energy ...
by Dominic Benna 2E
Thu Mar 04, 2021 8:32 pm
Forum: Phase Changes & Related Calculations
Topic: Vapor vs gas
Replies: 96
Views: 261

Re: Vapor vs gas

For this class they are the same for calculations.
by Dominic Benna 2E
Tue Feb 23, 2021 9:17 pm
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: negative sign
Replies: 12
Views: 210

Re: negative sign

A spontaneous reaction has a positive delta E, yet a negative delta G. So, in order to relate the two to each other, the negative sign is added.
by Dominic Benna 2E
Tue Feb 23, 2021 9:14 pm
Forum: Balancing Redox Reactions
Topic: "Leo" Oxidation Numbers
Replies: 26
Views: 70

Re: "Leo" Oxidation Numbers

Leo is just a term to help you understand oxidation and a way remember the difference between oxidation and reduction. LEO stands for "Loss of Electrons: Oxidation". It reminds you what oxidation is, when electrons are lost, as well as reminds you that oxidation is when electrons are lost,...
by Dominic Benna 2E
Tue Feb 23, 2021 11:03 am
Forum: Balancing Redox Reactions
Topic: e- in Redox Reactions
Replies: 11
Views: 32

Re: e- in Redox Reactions

Yes, you can. In a reduction, the electrons are gained, thus they would be on the reactants side. In oxidation, electrons are released, thus they would be on the products.
by Dominic Benna 2E
Sat Feb 20, 2021 6:39 pm
Forum: Thermodynamic Systems (Open, Closed, Isolated)
Topic: Free Energy
Replies: 41
Views: 132

Re: Free Energy

State functions are independent of the path taken, so their values are only dependent on the starting and ending values.
by Dominic Benna 2E
Sat Feb 20, 2021 6:33 pm
Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
Topic: Adiabatic
Replies: 26
Views: 67

Re: Adiabatic

That just means that no heat transfer occurs between the surrounding and the system.
by Dominic Benna 2E
Sat Feb 20, 2021 6:30 pm
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: Degeneracy and Entropy
Replies: 6
Views: 24

Re: Degeneracy and Entropy

As degeneracy increases so does entropy because as the amount of possible states increase, so does the randomness possible from it.
by Dominic Benna 2E
Sat Feb 20, 2021 6:23 pm
Forum: Concepts & Calculations Using Second Law of Thermodynamics
Topic: entropy positive value
Replies: 30
Views: 59

Re: entropy positive value

It is always positive for a spontaneous reaction.
by Dominic Benna 2E
Sat Feb 20, 2021 6:20 pm
Forum: Gibbs Free Energy Concepts and Calculations
Topic: Delta G and G naught
Replies: 38
Views: 109

Re: Delta G and G naught

Delta G naught is at standard conditions. You will know to use this in your equation if they give the standard condition values or say that the system is under standard conditions.
by Dominic Benna 2E
Sat Feb 20, 2021 6:13 pm
Forum: Concepts & Calculations Using First Law of Thermodynamics
Topic: Delta U and Delta H
Replies: 12
Views: 45

Re: Delta U and Delta H

Delta U = q+w
but at constant pressure, q=delta H
so delta u at constant pressure = delta H + w
by Dominic Benna 2E
Sun Feb 14, 2021 12:04 pm
Forum: Concepts & Calculations Using First Law of Thermodynamics
Topic: Reversible vs Irreversible Work
Replies: 5
Views: 27

Re: Reversible vs Irreversible Work

Reversible work is work done is infinitesimally small steps, or changes, so if the pressures are the same to start yet slowly change it is reversible. The second equation you wrote out is for reversible work. Irreversible work can be identified by one large step and large differences in pressure bet...
by Dominic Benna 2E
Sun Feb 14, 2021 11:59 am
Forum: Concepts & Calculations Using First Law of Thermodynamics
Topic: Kelvin conversion
Replies: 40
Views: 105

Re: Kelvin conversion

Lavelle has used just celsius + 273 to get the conversion to Kelvin, so I believe that will work most of the time. I believe, however, that the exact number to use is 273.15.
by Dominic Benna 2E
Sun Feb 14, 2021 11:57 am
Forum: Calculating Work of Expansion
Topic: Positive vs. Negative Work
Replies: 22
Views: 63

Re: Positive vs. Negative Work

Positive work is work that is done on the system, as it is gaining energy. Negative work is work done by the system, as it is losing energy.
by Dominic Benna 2E
Sun Feb 14, 2021 11:56 am
Forum: Calculating Work of Expansion
Topic: Integral Equations
Replies: 6
Views: 24

Re: Integral Equations

The integral for the work equation for a reversible reaction is not technically needed to solve the equation. It is shown to explain how we got it and why we use it, yet by simplification, the actual integral is not needed. The Ln of the two volumes works too.
by Dominic Benna 2E
Sun Feb 14, 2021 11:54 am
Forum: Calculating Work of Expansion
Topic: Sign of work
Replies: 25
Views: 53

Re: Sign of work

If the work is done on the system, it is gaining energy so the value should be positive. If the system is doing the work, then it is negative since it is losing energy.
by Dominic Benna 2E
Sun Feb 14, 2021 11:52 am
Forum: Calculating Work of Expansion
Topic: Difference between reversible and irreversible work of expansion
Replies: 10
Views: 42

Re: Difference between reversible and irreversible work of expansion

Reversible reactions have infinitely small changes applied to it, take much longer, and produce far more work done. Irreversible reactions involve one step, have a high pressure difference, and produce less work done.
by Dominic Benna 2E
Mon Feb 01, 2021 7:59 pm
Forum: Calculating Work of Expansion
Topic: What is V1 and V2
Replies: 12
Views: 35

Re: What is V1 and V2

The V1 and the V2 are the initial and final volumes of the system. The way I remember this is the bottom number on the integral is the lower bound and the top number is the upper bound of the integral.
by Dominic Benna 2E
Mon Feb 01, 2021 7:56 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: Negative Heat Capacities
Replies: 9
Views: 48

Re: Negative Heat Capacities

Heat capacities cannot be negative, because it is the measurement of heat supplied to something. It is the amount of heat to raise it's temperature, so it must be positive.
by Dominic Benna 2E
Mon Feb 01, 2021 7:54 pm
Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
Topic: Isolated Systems
Replies: 2
Views: 40

Isolated Systems

If a system is isochoric, isotermal, and isobaric, does that automatically make it an isolated system?
by Dominic Benna 2E
Mon Feb 01, 2021 7:48 pm
Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
Topic: isochoric
Replies: 10
Views: 298

Re: isochoric

The difference between isochoric and isometric is in their definition. Isochoric means there is no change in volume or that it has a constant volume. Isometric, on the other hand means that it has the same dimensions. I believe both terms can be used interchangeably.
by Dominic Benna 2E
Mon Feb 01, 2021 7:44 pm
Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
Topic: Irreversible vs Reversible
Replies: 3
Views: 33

Re: Irreversible vs Reversible

I believe that Lavelle explained that the difference between reversible and irreversible pathways is the magnitude of the change of the system, which depends on the if the system is at equilibrium or not. When the system is at equilibrium, an irreversible pathway is possible by slightly changing the...
by Dominic Benna 2E
Fri Jan 29, 2021 3:46 pm
Forum: Thermodynamic Systems (Open, Closed, Isolated)
Topic: Reversible Process
Replies: 2
Views: 48

Reversible Process

If there is a large pressure difference between the system and the surrounding, like the piston, why is the system not able to be reversed?
by Dominic Benna 2E
Fri Jan 29, 2021 3:43 pm
Forum: Thermodynamic Systems (Open, Closed, Isolated)
Topic: isolated system Drawing
Replies: 4
Views: 140

Re: isolated system Drawing

The pressure is constant because there is no within the system, including the change in pressure.
by Dominic Benna 2E
Fri Jan 29, 2021 3:42 pm
Forum: Thermodynamic Systems (Open, Closed, Isolated)
Topic: intensive vs extensive
Replies: 12
Views: 254

Re: intensive vs extensive

Extensive properties depend on the amount being measure, yet intensive do not. For example, mass is extensive and density is intensive.
by Dominic Benna 2E
Fri Jan 29, 2021 3:40 pm
Forum: Thermodynamic Systems (Open, Closed, Isolated)
Topic: Open Systems
Replies: 15
Views: 226

Re: Open Systems

All thermodynamic equations should work because open systems deal with matter and heat.
by Dominic Benna 2E
Fri Jan 29, 2021 3:39 pm
Forum: Thermodynamic Systems (Open, Closed, Isolated)
Topic: Isolated Systems
Replies: 8
Views: 40

Isolated Systems

Will we be working with isolated systems mathematically if there is no change in energy?
by Dominic Benna 2E
Thu Jan 21, 2021 10:12 pm
Forum: Phase Changes & Related Calculations
Topic: Phase changes and state properties
Replies: 5
Views: 24

Re: Phase changes and state properties

State properties only take into account final values, not the path taken. Enthalpy is a state property. Since sublimation is the transition from solid to vapor, then that must equal fusion(solid to liquid) plus vaporization(liquid to vapor) of the same material.
by Dominic Benna 2E
Thu Jan 21, 2021 10:08 pm
Forum: Phase Changes & Related Calculations
Topic: phase transition
Replies: 13
Views: 55

Re: phase transition

The reason why it's temperature doesn't increase is because the energy that is being given to the system is being used break bonds for the phase change to happen.
by Dominic Benna 2E
Thu Jan 21, 2021 10:05 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: Ka vs. Kb
Replies: 30
Views: 131

Re: Ka vs. Kb

Ka and Kb are both found by using [P]/[R]. The difference between the two is that Ka is used for acids and Kb is used for bases.
by Dominic Benna 2E
Thu Jan 21, 2021 10:03 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Changes in partial pressure
Replies: 7
Views: 47

Changes in partial pressure

How do you find out how a reaction will react to a change in partial pressure of either its reactants or products?
by Dominic Benna 2E
Thu Jan 21, 2021 9:59 pm
Forum: Phase Changes & Related Calculations
Topic: clarification
Replies: 4
Views: 63

Re: clarification

Work (w) and heat (q) are both dependent on the paths they taken. This means that their quantities are based on the past and not just their current quality. This means that they are both not state variables.
by Dominic Benna 2E
Sat Jan 16, 2021 10:58 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Kw constant
Replies: 25
Views: 64

Re: Kw constant

[H2O] is left out because it is found in large amounts on both the product and reactant side of the equation. This means, when calculating for Kw, the amounts of [H20] would just cancel each other out.
by Dominic Benna 2E
Sat Jan 16, 2021 10:56 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: pH of Weak Acids
Replies: 11
Views: 80

Re: pH of Weak Acids

Strong acids do have a lower pH than weaker acids, but I am guessing that it was due to the concentration of the weak acid in those questions that caused the pH to drop so much. 0.001M of a strong acid will completely dissociate, but only create 0.001M of H3O+, but 0.1M of a week acid could create m...
by Dominic Benna 2E
Sat Jan 16, 2021 10:53 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Ka x Kb
Replies: 11
Views: 60

Re: Ka x Kb

Yes. Kw will always be equal to 10^-14, so if you have either the Kb or Ka values, you can find the other easily!
by Dominic Benna 2E
Sat Jan 16, 2021 10:52 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Week 2 Sapling #5
Replies: 1
Views: 20

Week 2 Sapling #5

I am having a hard time with this one question on the week two sapling homework. I believe that I am getting the right concentration for [OH-] and plugging in the right numbers into the Kb equation to find the concentration of [B], but my percent pronated number just doesn't make sense, as it is abo...
by Dominic Benna 2E
Sat Jan 16, 2021 10:49 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: ICE Box
Replies: 28
Views: 102

Re: ICE Box

I think ICE boxes are especially helpful to use when working with weak acids and bases. However, I think it is just good practice to also use them with strong acids and bases, however, I do not think it is necessary.
by Dominic Benna 2E
Sat Jan 09, 2021 5:03 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Change inn temperature
Replies: 6
Views: 40

Change inn temperature

How do I know how K will be affected based on a change in temperature? Does is depend on if the reaction is endothermic or exothermic?
by Dominic Benna 2E
Sat Jan 09, 2021 5:01 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Partial pressure vs. concentration
Replies: 3
Views: 12

Re: Partial pressure vs. concentration

You would use partial pressure when finding Kp or are only dealing with gases in the equation. If the reactants and products are not all gases or are asked for Kc, then you would use concentration.
by Dominic Benna 2E
Sat Jan 09, 2021 4:59 pm
Forum: Ideal Gases
Topic: Kc vs Kp
Replies: 109
Views: 1004

Re: Kc vs Kp

Kc is always used when you are given the molar concentrations or the moles of the products or reactants. Kp is used when you have only gases, or if, in the equation, it mentions atm/bar for the units.
by Dominic Benna 2E
Sat Jan 09, 2021 2:58 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: Q and K
Replies: 17
Views: 147

Re: Q and K

Only Q would change, so you would only need to find the value of Q in that situation. The only time that K changes is if the temperature changes, not if the amount of reactants or products changes.
by Dominic Benna 2E
Sat Jan 09, 2021 2:56 pm
Forum: Ideal Gases
Topic: value of R
Replies: 24
Views: 116

Re: value of R

It basically depends of the units in the equation. However, I think Lavelle said that we would be using atm mostly, so the most likely value you would be using for R would be 8.206 x 10^-2.
by Dominic Benna 2E
Mon Dec 07, 2020 5:32 pm
Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
Topic: Strong acids and bases vs. weak acids and bases
Replies: 3
Views: 47

Strong acids and bases vs. weak acids and bases

Will we have to identify if an acid or base is strong or weak based off of pH? If so, what is the pH range for a strong acid verses weak acids, and the same for bases.
by Dominic Benna 2E
Mon Dec 07, 2020 5:28 pm
Forum: Naming
Topic: Roman numeral
Replies: 5
Views: 41

Re: Roman numeral

You find the oxidation number of the metal by looking at the overall charge of the coordination compound and the individual charges of the ligand and atoms within the compound. You use the metal to balance the charges within the coordination compound to match the overall charge of the compound.
by Dominic Benna 2E
Mon Dec 07, 2020 5:16 pm
Forum: Bronsted Acids & Bases
Topic: O2- in water makes 2 OH-?
Replies: 3
Views: 44

Re: O2- in water makes 2 OH-?

When the hydrogen breaks from the H20 to the O2-, the H20 becomes one of the OH- and the O2- that gained an H becomes OH- too. That is why you get two moles of OH- for every mole of O2-.
by Dominic Benna 2E
Mon Dec 07, 2020 4:58 pm
Forum: Lewis Acids & Bases
Topic: sapling #6
Replies: 19
Views: 148

Re: sapling #6

The H in the COOH of the CH3COOH breaks off as a positive proton, so it makes it an acid.
by Dominic Benna 2E
Mon Dec 07, 2020 4:52 pm
Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
Topic: From pOH- to [H+]
Replies: 3
Views: 29

From pOH- to [H+]

What equation should I use to convert a pOH- value into a [H+] value in molarity?
by Dominic Benna 2E
Fri Dec 04, 2020 1:55 pm
Forum: Properties & Structures of Inorganic & Organic Bases
Topic: Is trichloroacetic acid stronger than acetic acid?
Replies: 5
Views: 189

Re: Is trichloroacetic acid stronger than acetic acid?

Yes it is. The reasoning behind it being stronger is that the anion created from trichloroacetic is more stable than acetic acid. This is due to the Cl's delocalizing the negative charge of the oxygen and the resonance structure that is created when the H is broken off.
by Dominic Benna 2E
Fri Dec 04, 2020 1:52 pm
Forum: Properties & Structures of Inorganic & Organic Bases
Topic: Equilibrium sign
Replies: 9
Views: 379

Re: Equilibrium sign

No because there will be theoretically a 100% dissociation of the acid or base.
by Dominic Benna 2E
Fri Dec 04, 2020 1:38 pm
Forum: Properties & Structures of Inorganic & Organic Acids
Topic: H2O Notation
Replies: 5
Views: 56

Re: H2O Notation

H20 should be labeled a liquid because it is the solvent of the aqueous solution. An aqueous solution is created when water is the solvent, so H20 by itself wouldn't be aqueous.
by Dominic Benna 2E
Fri Dec 04, 2020 1:35 pm
Forum: Properties & Structures of Inorganic & Organic Acids
Topic: pH Chart
Replies: 16
Views: 125

Re: pH Chart

I believe that we just need to know relatively their pH. For example that vinegar is acidic and bleach is basic. I don't think we have to know their exact values however.
by Dominic Benna 2E
Fri Dec 04, 2020 1:33 pm
Forum: Properties & Structures of Inorganic & Organic Bases
Topic: Inorganic and Organic
Replies: 7
Views: 69

Re: Inorganic and Organic

The difference between organic and inorganic bases is that an organic base contains carbon atoms where inorganic bases don't.
by Dominic Benna 2E
Wed Nov 25, 2020 5:51 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Coordinate Compounds
Replies: 5
Views: 55

Coordinate Compounds

Are coordinate compounds only possible with a transition metal cation? Or can any ionic compound be a coordinate compound?
by Dominic Benna 2E
Wed Nov 25, 2020 5:47 pm
Forum: Sigma & Pi Bonds
Topic: Delocalized Pi Bonds
Replies: 4
Views: 61

Delocalized Pi Bonds

What is a delocalized pi bond? How are you able to recognize and point out what is a delocalized pi bond?
by Dominic Benna 2E
Wed Nov 25, 2020 5:44 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Lecture #20
Replies: 4
Views: 71

Re: Lecture #20

The position of the atoms determines its shape, and lone pairs influence where the position of the atoms will be. It he were to ask for the electron configuration, lone pairs would be taken into consideration when determining the shape; however, for finding the shape of a molecule, the positions of ...
by Dominic Benna 2E
Wed Nov 25, 2020 5:39 pm
Forum: Hybridization
Topic: Sapling Week 7 & 8 HW Question 11
Replies: 14
Views: 137

Re: Sapling Week 7 & 8 HW Question 11

First, you would want to count the lone pairs and the bonds. Since this one has 4, it would be sp^3. One orbital from the s-orbital and 3 from the p-orbital.
by Dominic Benna 2E
Wed Nov 25, 2020 5:38 pm
Forum: Hybridization
Topic: Hybridization with double bonds
Replies: 4
Views: 30

Hybridization with double bonds

When there is a double bond is involved, does that count towards the hybridization of an atom? Would a central atom with two single bonds and a double bond be sp^3 or sp^3d?
by Dominic Benna 2E
Thu Nov 19, 2020 9:42 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 Dipole-Induced Dipole
Replies: 5
Views: 63

Dipole-Dipole vs Dipole-Induced Dipole

What is the difference between a Dipole-Dipole interaction and a Dipole-Induced-Dipole interation?

Would their relative strengths be different too?
by Dominic Benna 2E
Thu Nov 19, 2020 9:39 pm
Forum: Sigma & Pi Bonds
Topic: Triple bond?
Replies: 21
Views: 169

Re: Triple bond?

A triple bond has 1 sigma and 2 pi
by Dominic Benna 2E
Thu Nov 19, 2020 9:31 pm
Forum: Electronegativity
Topic: Sapling #15
Replies: 9
Views: 94

Re: Sapling #15

Florine is extremely electronegative. This means that this molecule will be polar, and because it has a hydrogen, it can form a hydrogen bond. For reference, O, N, and, F are the three atoms that, when bonded to a hydrogen, can form hydrogen bonds.
by Dominic Benna 2E
Thu Nov 19, 2020 9:28 pm
Forum: Electronegativity
Topic: determining electronegativity
Replies: 31
Views: 264

Re: determining electronegativity

It increases as you go right across a period, and it decreases as you go down a group. So, Florine, for example, is the most electronegative atom.
by Dominic Benna 2E
Thu Nov 19, 2020 9:27 pm
Forum: Electronegativity
Topic: Electronegativity difference
Replies: 8
Views: 70

Re: Electronegativity difference

Carbon and hydrogen have a very similar electronegativity. That is why when they show a chart of the electronegativity of atoms they place hydrogen above carbon. But yes, looking straight off a periodic table it is not noticeable.
by Dominic Benna 2E
Sun Nov 15, 2020 8:48 pm
Forum: Ionic & Covalent Bonds
Topic: Sapling #13
Replies: 8
Views: 37

Re: Sapling #13

See how many electron pairs connected to either a N,O, or F atom and each one can pair with one water molecule.
by Dominic Benna 2E
Sun Nov 15, 2020 8:39 pm
Forum: Dipole Moments
Topic: Strength of Dipole-Dipole vs Induced Dipole-Dipole
Replies: 4
Views: 17

Re: Strength of Dipole-Dipole vs Induced Dipole-Dipole

From what Professor Lavelle said in lecture, they generally have the same force.
by Dominic Benna 2E
Sun Nov 15, 2020 8:38 pm
Forum: Dipole Moments
Topic: Hydrogen Bonding
Replies: 3
Views: 10

Re: Hydrogen Bonding

It is not so much that the electrons are shared. Instead it is the attraction between the partially positive charge of the hydrogen and the partially negative charge of the other atom that created the hydrogen bond.
by Dominic Benna 2E
Sun Nov 15, 2020 8:36 pm
Forum: Octet Exceptions
Topic: Identifying Radicals
Replies: 24
Views: 197

Re: Identifying Radicals

You can tell if there is an odd number of valance electrons or on the diagram there is a lone electron.
by Dominic Benna 2E
Sun Nov 15, 2020 8:34 pm
Forum: Formal Charge and Oxidation Numbers
Topic: Sapling week 5 & 6 #5
Replies: 20
Views: 131

Re: Sapling week 5 & 6 #5

The formal charge on carbon would be -2, not -1
by Dominic Benna 2E
Sun Nov 08, 2020 8:32 pm
Forum: Ionic & Covalent Bonds
Topic: Coordinate Covalent Bond
Replies: 4
Views: 20

Re: Coordinate Covalent Bond

A coordinate covalent bond is when the two electrons that form a covalent bond come from the same atom, rather than one electron from each.
by Dominic Benna 2E
Sun Nov 08, 2020 8:29 pm
Forum: Ionic & Covalent Bonds
Topic: Sapling #2
Replies: 6
Views: 39

Re: Sapling #2

Press the more option on the top of that window. From there you should be able to choose either a positive or negative charge to add to the atoms.
by Dominic Benna 2E
Sun Nov 08, 2020 8:28 pm
Forum: Ionic & Covalent Bonds
Topic: Octet rule exceptions
Replies: 15
Views: 77

Re: Octet rule exceptions

Those are the exceptions because they will not get up to 8 valence electrons. They will either gain electrons to gain a full shell of two electrons or lose a certain number of electrons to have a full shell of two valence electrons.
by Dominic Benna 2E
Sun Nov 08, 2020 8:25 pm
Forum: Ionic & Covalent Bonds
Topic: Extra Valence Electrons
Replies: 10
Views: 69

Re: Extra Valence Electrons

They are the exceptions to the octet rule because they can have d-oribitals.
by Dominic Benna 2E
Sun Nov 08, 2020 8:24 pm
Forum: Ionic & Covalent Bonds
Topic: Covalent bonds and distortion
Replies: 5
Views: 48

Re: Covalent bonds and distortion

It is more distorted because the electrons are being shared more. When the bond is more covalent, that means that the electrons are being shared more. Then there will be a distortion between the two atoms.
by Dominic Benna 2E
Sat Oct 31, 2020 8:08 pm
Forum: Trends in The Periodic Table
Topic: Periodic Table & Electron Affinity
Replies: 11
Views: 90

Re: Periodic Table & Electron Affinity

noelle_lipschutz_3F wrote:Can someone explain how to use the periodic table to determine electron affinity?


I believe that affinity increases as you go right down a period it increases and decreases as you go down a row!
by Dominic Benna 2E
Sat Oct 31, 2020 8:04 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Ionization Energy
Replies: 3
Views: 42

Ionization Energy

So why is the 2nd ionization energy so much higher than the first ionization energy for atoms?
by Dominic Benna 2E
Sat Oct 31, 2020 8:01 pm
Forum: Trends in The Periodic Table
Topic: In class question
Replies: 8
Views: 62

Re: In class question

You can't find the radius of an atom off of a singular atom, but you can find the radius of a single atom be finding the distance between two nuclei and dividing by two.
by Dominic Benna 2E
Sat Oct 31, 2020 7:59 pm
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: Question 1D.25
Replies: 6
Views: 51

Re: Question 1D.25

a) would be the right answer because there are only s and p orbitals in the second energy level
by Dominic Benna 2E
Sat Oct 31, 2020 7:57 pm
Forum: Quantum Numbers and The H-Atom
Topic: Spin state
Replies: 25
Views: 222

Re: Spin state

If an electron spin state is +1/2, it means the electron is spinning upwards/clockwise on its axis. If the spin state is -1/2, the electron is spinning downwards/counterclockwise on its axis. I know that is what it says in the book and the diagrams Lavelle showed us, but what exactly does it mean b...
by Dominic Benna 2E
Sat Oct 24, 2020 8:07 pm
Forum: Heisenberg Indeterminacy (Uncertainty) Equation
Topic: Sapling #19
Replies: 4
Views: 74

Sapling #19

For the second part of #19 on the sapling homework, I keep getting 5.67x10^-2 m/s, but it says that it is incorrect.

This is the question for reference:
What is the minimum uncertainty in a helium atom's velocity if the position is known to be 1.4 angstroms
by Dominic Benna 2E
Thu Oct 22, 2020 7:57 pm
Forum: Significant Figures
Topic: Midterm
Replies: 9
Views: 118

Midterm

Will there be questions on the midterm where we will have to choose between two answers with differing sig figs?
by Dominic Benna 2E
Thu Oct 22, 2020 7:55 pm
Forum: SI Units, Unit Conversions
Topic: SI Conversions
Replies: 11
Views: 84

SI Conversions

Will we have to know how to convert between kg to g or km to m for the midterm?
by Dominic Benna 2E
Thu Oct 22, 2020 7:51 pm
Forum: Heisenberg Indeterminacy (Uncertainty) Equation
Topic: Indeterminacy Problem
Replies: 3
Views: 28

Indeterminacy Problem

Hey guys,
I have been working on this problem but I can't seem to get it right. Thought you guys could help me with the steps.

A bowling ball of mass 8.00kg is rolled down a bowling alley lane at 5.00 +/- 5.0 ms-1. What is the minimum uncertainty in its position?
by Dominic Benna 2E
Thu Oct 22, 2020 7:44 pm
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: Finding the wavelength between two levels
Replies: 3
Views: 58

Finding the wavelength between two levels

I have been having some trouble trying to find the n-levels that an electron will be excited or dropped to based on a given wavelength. For example: In the ultraviolet spectrum of atomic hydrogen, a line is observed at 102.6nm. Determine the values for n for the initial and final energy levels of th...
by Dominic Benna 2E
Thu Oct 22, 2020 7:37 pm
Forum: Student Social/Study Group
Topic: TA/UA Midterm Review Sessions
Replies: 3
Views: 50

Re: TA/UA Midterm Review Sessions

Ryan_Kien_1L wrote:Review sessions happen every week. The schedule is posted here: https://lavelle.chem.ucla.edu/wp-conten ... PL_ALL.pdf


Thank you!
by Dominic Benna 2E
Thu Oct 22, 2020 7:36 pm
Forum: Student Social/Study Group
Topic: Midterm study
Replies: 5
Views: 45

Re: Midterm study

I will be reviewing the modules, but I think that the best way to study for the midterm would be to do the practice problems Lavelle assigned in the textbook. But that's just my opinion!
by Dominic Benna 2E
Wed Oct 14, 2020 10:56 pm
Forum: *Black Body Radiation
Topic: What is Black Body?
Replies: 35
Views: 573

Re: What is Black Body?

Didn't Lavelle also say that we didn't necessarily need to know about Black Bodies for the course?
by Dominic Benna 2E
Wed Oct 14, 2020 10:53 pm
Forum: Photoelectric Effect
Topic: Photoelectric Effect Module
Replies: 6
Views: 86

Re: Photoelectric Effect Module

Hi! I believe you would approach the problem E = hv and c = λv. You're given E, and if you rearrange the E = hv equation, you get v = E/h. When you plug that into the c = λv equation, you'll get c = λ(E/h). Multiply both sides by h, divide both sides by E, and then solve for λ. Hope this helps That...
by Dominic Benna 2E
Wed Oct 14, 2020 10:51 pm
Forum: Student Social/Study Group
Topic: Post All Chemistry Jokes Here
Replies: 8812
Views: 1496158

Re: Post All Chemistry Jokes Here

What is HIJKLMNO?



H2O
by Dominic Benna 2E
Wed Oct 14, 2020 10:46 pm
Forum: Photoelectric Effect
Topic: Photoelectric Effect Module
Replies: 6
Views: 86

Re: Photoelectric Effect Module

ofc!
by Dominic Benna 2E
Wed Oct 14, 2020 10:44 pm
Forum: Photoelectric Effect
Topic: Photoelectric Effect Module
Replies: 6
Views: 86

Re: Photoelectric Effect Module

First, you would need to plug this number into the E = hV equation as your E. From there you get your frequency. Then you plug that into the c= λV equation to get your wavelength.
by Dominic Benna 2E
Fri Oct 09, 2020 7:32 pm
Forum: Molarity, Solutions, Dilutions
Topic: Molar Mass Stated in Sapling HW
Replies: 10
Views: 66

Re: Molar Mass Stated in Sapling HW

The + - 10 just symbolizes that the amount could vary anywhere between 90-110 g/mol.
by Dominic Benna 2E
Fri Oct 09, 2020 7:28 pm
Forum: Significant Figures
Topic: Sapling HW #4
Replies: 31
Views: 356

Re: Sapling HW #4

A trailing zero without a decimal point does not make the number more precise, so they do not count as sig figs. The zeros are just place holders to show the true value of the number.
by Dominic Benna 2E
Fri Oct 09, 2020 7:22 pm
Forum: Molarity, Solutions, Dilutions
Topic: What does mmol stand for?
Replies: 33
Views: 375

Re: What does mmol stand for?

mmol just refers to the milli-mol. Or 10^-3 of a mole.
by Dominic Benna 2E
Fri Oct 09, 2020 7:19 pm
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: Frequencies and Wavelengths of Colors in the Visible Light Spectrum
Replies: 4
Views: 69

Re: Frequencies and Wavelengths of Colors in the Visible Light Spectrum

I believe your range is pretty accurate with violet being around 380 nm and red being around 710 nm. Because visible light is a spectrum of color, I doubt you will have to know the specific frequency of ROYGBV since each color covers a range of wavelengths. :) Lavelle did also say that making it mo...
by Dominic Benna 2E
Fri Oct 09, 2020 7:14 pm
Forum: SI Units, Unit Conversions
Topic: Temperature
Replies: 14
Views: 126

Re: Temperature

I believe that it will mainly depend on the question and the units given originally.

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