Search found 100 matches

by Jack Riley 4f
Tue Mar 10, 2020 9:35 pm
Forum: First Order Reactions
Topic: Equilibrium constant and elementary reaction rate constants
Replies: 5
Views: 22

Re: Equilibrium constant and elementary reaction rate constants

K=(k'/k) is the relationship between equilibrium constant and rate constants
by Jack Riley 4f
Tue Mar 10, 2020 9:34 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: Chemical Equilibrium biological examples
Replies: 2
Views: 52

Re: Chemical Equilibrium biological examples

An example is a neuron and its action potential. It is at equilibrium, but when it receives a signal, Na+ ions rush in causing it to veer from equilibrium until the K+ ions rush out, returning it to equilibrium.
by Jack Riley 4f
Tue Mar 10, 2020 9:32 pm
Forum: *Enzyme Kinetics
Topic: Poison a Catalyst
Replies: 3
Views: 44

Re: Poison a Catalyst

It may matter conceptually, but I doubt quantitatively. Poisoning a catalyst is to cause it to lose its function.
by Jack Riley 4f
Tue Mar 10, 2020 9:31 pm
Forum: *Enzyme Kinetics
Topic: Collision model
Replies: 2
Views: 33

Re: Collision model

It helps us determine which collisions occur with enough energy to overcome the activation energy. This helps us determine A in the Arrhenius equation
by Jack Riley 4f
Tue Mar 10, 2020 9:30 pm
Forum: Phase Changes & Related Calculations
Topic: Heating Curve
Replies: 2
Views: 79

Re: Heating Curve

probably not. the calculations should be sufficient
by Jack Riley 4f
Mon Mar 02, 2020 6:10 pm
Forum: General Rate Laws
Topic: Order
Replies: 5
Views: 61

Re: Order

you look at the graph and compare it with the 3 possible orders to determine which one best fits the graph shown
by Jack Riley 4f
Mon Mar 02, 2020 6:07 pm
Forum: Kinetics vs. Thermodynamics Controlling a Reaction
Topic: instantaneous rate
Replies: 16
Views: 117

Re: instantaneous rate

It is more precise for that specific moment in time
by Jack Riley 4f
Mon Mar 02, 2020 6:07 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Cell Diagram for 6L.5(b)
Replies: 2
Views: 15

Re: Cell Diagram for 6L.5(b)

the TA's have said that the book writes it in different format sometimes but that we should stick to what we were taught in lecture and we'll be ok
by Jack Riley 4f
Mon Mar 02, 2020 6:06 pm
Forum: Balancing Redox Reactions
Topic: Electrochemical series.
Replies: 4
Views: 40

Re: Electrochemical series.

It is a list of reduction half reactions
by Jack Riley 4f
Mon Feb 24, 2020 12:04 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Platinum
Replies: 5
Views: 56

Re: Platinum

It's a common electrode because it is inert and doesn't interfere with the redox reaction
by Jack Riley 4f
Mon Feb 24, 2020 12:04 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Salt bridge
Replies: 6
Views: 50

Re: Salt bridge

It keeps the 2 solutions neutral so electrons can continue transferring
by Jack Riley 4f
Mon Feb 24, 2020 12:03 pm
Forum: Balancing Redox Reactions
Topic: Oxidizing/Reducing Agent
Replies: 8
Views: 57

Re: Oxidizing/Reducing Agent

the oxidizing agent gains electrons and the reducing agent loses electrons
by Jack Riley 4f
Mon Feb 24, 2020 12:02 pm
Forum: Balancing Redox Reactions
Topic: Platinum in cell diagram
Replies: 10
Views: 80

Re: Platinum in cell diagram

You need a metal to conduct the electrons and platinum is inert and doesn't interfere with the redox reaction
by Jack Riley 4f
Tue Feb 18, 2020 8:58 pm
Forum: Administrative Questions and Class Announcements
Topic: Test #2
Replies: 4
Views: 122

Re: Test #2

It will probably include Gibbs free energy and all the material that we get through this week (electrochemistry)
by Jack Riley 4f
Tue Feb 18, 2020 8:57 pm
Forum: Gibbs Free Energy Concepts and Calculations
Topic: 5J.15
Replies: 4
Views: 50

Re: 5J.15

My book also says 150 degrees celsius which matches up with the 423 K
by Jack Riley 4f
Tue Feb 18, 2020 8:56 pm
Forum: Entropy Changes Due to Changes in Volume and Temperature
Topic: converting T to kelvin
Replies: 21
Views: 262

Re: converting T to kelvin

when talking about delta T then yes it is ok because they are the same in that respect. However, when doing calculations with T you should convert to K because most R values are given with K as the unit
by Jack Riley 4f
Tue Feb 18, 2020 8:55 pm
Forum: Thermodynamic Systems (Open, Closed, Isolated)
Topic: Constant R
Replies: 15
Views: 189

Re: Constant R

Just look at the units needed in the problem and choose the R with those units same units
by Jack Riley 4f
Tue Feb 18, 2020 8:53 pm
Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
Topic: UA's
Replies: 3
Views: 68

Re: UA's

I have found the UA sessions to be very helpful so to anyone who is struggling go to as many as you can!
by Jack Riley 4f
Tue Feb 11, 2020 1:14 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: Questions about Equation Sheet
Replies: 3
Views: 47

Re: Questions about Equation Sheet

Cp = 5/2R and Cv = 3/2R both apply to monoatomic gases. Cp is for constant pressure and Cv is for constant volume
by Jack Riley 4f
Tue Feb 11, 2020 1:10 pm
Forum: Concepts & Calculations Using First Law of Thermodynamics
Topic: Internal energy of ideal gas
Replies: 6
Views: 121

Re: Internal energy of ideal gas

the change in internal energy is 0 at constant temperature, however the internal energy itself is not necessarily 0 at constant temperature
by Jack Riley 4f
Tue Feb 11, 2020 1:08 pm
Forum: Entropy Changes Due to Changes in Volume and Temperature
Topic: Change in entropy of an irreversible process.
Replies: 3
Views: 42

Re: Change in entropy of an irreversible process.

delta S of the surroundings does equal 0 because it is free expansion, but delta S total must still increase so that only leaves delta S of the system to contribute to this. Thus, delta S total = delta S system =/= 0
by Jack Riley 4f
Tue Feb 11, 2020 1:01 pm
Forum: Concepts & Calculations Using First Law of Thermodynamics
Topic: 4.17
Replies: 1
Views: 36

4.17

4.17 A technician carries out the reaction 2 SO2(g) 1 O2(g) S 2 SO3(g) at 25 8C and 1.00 atm in a cylinder fitted with a piston and maintained at constant pressure. Initially, 0.030 mol SO2 and 0.030 mol O2 are present in the cylinder. The technician then adds a catalyst to initiate the reaction. (a...
by Jack Riley 4f
Sun Feb 09, 2020 9:45 pm
Forum: Concepts & Calculations Using Second Law of Thermodynamics
Topic: 4F13
Replies: 3
Views: 57

4F13

4F.13 Use data in Table 4C.1 or Appendix 2A to calculate the entropy change for (a) the freezing of 1.00 mol H2O(l) at 0.00 8C; (b) the vaporization of 50.0 g of ethanol, C2H5OH, at 351.5 K.

How would you solve this?
by Jack Riley 4f
Mon Feb 03, 2020 7:59 pm
Forum: Calculating Work of Expansion
Topic: Intergral
Replies: 6
Views: 50

Re: Intergral

we won't actually have to do this
by Jack Riley 4f
Mon Feb 03, 2020 7:58 pm
Forum: Calculating Work of Expansion
Topic: Calculus on The Midterm
Replies: 8
Views: 64

Re: Calculus on The Midterm

the only calculus so far is w=integral(PdV)
by Jack Riley 4f
Mon Feb 03, 2020 7:57 pm
Forum: Calculating Work of Expansion
Topic: Work done by an ideal gas at isothermal, reversibile expansion
Replies: 3
Views: 39

Re: Work done by an ideal gas at isothermal, reversibile expansion

the equation for an isothermal, reversible expansion is w=-nRTln(V2/V1)
by Jack Riley 4f
Mon Feb 03, 2020 7:56 pm
Forum: Thermodynamic Systems (Open, Closed, Isolated)
Topic: Closed Systems
Replies: 14
Views: 186

Re: Closed Systems

deltaU = q + w so you can change it by adding heat or doing work
by Jack Riley 4f
Mon Feb 03, 2020 7:54 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: Combustion
Replies: 5
Views: 41

Re: Combustion

at 25 degrees celsius, water is a liquid, so I would assume you use the liquid form.
by Jack Riley 4f
Mon Jan 27, 2020 8:50 pm
Forum: Administrative Questions and Class Announcements
Topic: Fall Quarter Final?
Replies: 12
Views: 241

Re: Fall Quarter Final?

They're still available throughout the quarter I have been told
by Jack Riley 4f
Mon Jan 27, 2020 8:50 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: Calorimeter
Replies: 7
Views: 53

Re: Calorimeter

A calorimeter is used to measure heat of a rxn
by Jack Riley 4f
Mon Jan 27, 2020 8:49 pm
Forum: Administrative Questions and Class Announcements
Topic: final exam
Replies: 6
Views: 111

Re: final exam

you can still pick them up week 4 so don't worry
by Jack Riley 4f
Mon Jan 27, 2020 8:48 pm
Forum: Phase Changes & Related Calculations
Topic: Enthalpy of sublimation?
Replies: 8
Views: 51

Re: Enthalpy of sublimation?

the enthalpy of sublimation is the sum of the enthalpy of vaporization and fusion
by Jack Riley 4f
Mon Jan 27, 2020 8:48 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: Stirrer in Calorimeter?
Replies: 3
Views: 20

Re: Stirrer in Calorimeter?

It helps mix together the solvent and solute so the rxn can go to completion
by Jack Riley 4f
Thu Jan 23, 2020 4:08 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: Approximation
Replies: 5
Views: 41

Re: Approximation

If K < 10^-3 then you are able to approximate.
by Jack Riley 4f
Thu Jan 23, 2020 4:08 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Calculating Kp
Replies: 6
Views: 43

Re: Calculating Kp

You can calculate Kp from Kc by using Pv=nRT if given concentrations and enough info. ICE tables are also used for partial pressures as well, though.
by Jack Riley 4f
Thu Jan 23, 2020 4:07 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: Endothermic Reaction.
Replies: 7
Views: 59

Re: Endothermic Reaction.

If delta H is positive, then it is endothermic
by Jack Riley 4f
Thu Jan 23, 2020 4:06 pm
Forum: Phase Changes & Related Calculations
Topic: Order to Read Book
Replies: 3
Views: 28

Re: Order to Read Book

Just follow what he tells us to read on the syllabus.
by Jack Riley 4f
Thu Jan 23, 2020 4:05 pm
Forum: Phase Changes & Related Calculations
Topic: Steam vs liquid
Replies: 7
Views: 51

Re: Steam vs liquid

Steam has more heat energy due to the fact that that energy was inputted in order to vaporize the H2O.
by Jack Riley 4f
Tue Jan 14, 2020 1:58 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: ICE charts on tests/exams
Replies: 8
Views: 64

Re: ICE charts on tests/exams

I would say yes because partial credit is huge on Lavelle's tests so you should write it out just in case.
by Jack Riley 4f
Tue Jan 14, 2020 1:57 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Why Ignore Liquid or Solid Volume When Calculating K
Replies: 7
Views: 52

Re: Why Ignore Liquid or Solid Volume When Calculating K

Liquids and solids cannot be dissolved or have their pressures changed in solution so they are not factored in when calculating K.
by Jack Riley 4f
Tue Jan 14, 2020 1:56 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Strong Acids/Bases
Replies: 4
Views: 33

Re: Strong Acids/Bases

Strong acids and bases completely dissociate in solution while weak acids and bases only partially dissociate.
by Jack Riley 4f
Tue Jan 14, 2020 1:56 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Change on Same Side
Replies: 6
Views: 55

Re: Change on Same Side

If you increase N2, then H2 will decrease because the reaction will move toward the right.
by Jack Riley 4f
Tue Jan 14, 2020 1:55 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: 5I.13
Replies: 3
Views: 36

Re: 5I.13

The closer K is to 1, the more stable the reaction is because then the conc of reactants and products is almost equal and neither is favored
by Jack Riley 4f
Sun Jan 12, 2020 8:10 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Thinking point 5J
Replies: 4
Views: 40

Re: Thinking point 5J

It would have no effect because solids are not part of the equation
by Jack Riley 4f
Sun Jan 12, 2020 8:10 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Kp
Replies: 6
Views: 48

Re: Kp

K is the general equilibrium constant while Kp refers to the equilibrium constant when using partial pressures.
by Jack Riley 4f
Sun Jan 12, 2020 8:08 pm
Forum: Ideal Gases
Topic: Ideal gases equation
Replies: 3
Views: 33

Re: Ideal gases equation

number of moles
by Jack Riley 4f
Sun Jan 12, 2020 8:08 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Different types of K
Replies: 9
Views: 57

Re: Different types of K

K is the general equilibrium constant while Kc specifically refers to the equilibrium constant of molar concentrations
by Jack Riley 4f
Sun Jan 12, 2020 8:06 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Studying tips
Replies: 10
Views: 59

Re: Studying tips

Do every hw problem on the syllabus
by Jack Riley 4f
Tue Dec 03, 2019 11:19 am
Forum: Properties & Structures of Inorganic & Organic Bases
Topic: Stronger Acid 6C.21
Replies: 3
Views: 93

Re: Stronger Acid 6C.21

acetic acid has a less stable conjugate base so it is a weaker acid.
by Jack Riley 4f
Tue Dec 03, 2019 11:18 am
Forum: Interionic and Intermolecular Forces (Ion-Ion, Ion-Dipole, Dipole-Dipole, Dipole-Induced Dipole, Dispersion/Induced Dipole-Induced Dipole/London Forces, Hydrogen Bonding)
Topic: TEST 2 POLAR molecule
Replies: 6
Views: 57

Re: TEST 2 POLAR molecule

It is a tetrahedral molecule, so the dipoles only cancel out when all 4 atoms are the same.
by Jack Riley 4f
Tue Dec 03, 2019 11:10 am
Forum: Amphoteric Compounds
Topic: water
Replies: 4
Views: 39

Re: water

It depends what it is reacting with. In an acidic solution, it acts as a base and vice versa
by Jack Riley 4f
Tue Dec 03, 2019 11:08 am
Forum: Amphoteric Compounds
Topic: Amphoteric/acidic/basic
Replies: 5
Views: 65

Re: Amphoteric/acidic/basic

You need to check what is bonded to the oxygen. If it is a metal, then it is basic. If it is a nonmetal, it is acidic. The metalloids can form amphoteric oxides.
by Jack Riley 4f
Tue Dec 03, 2019 11:06 am
Forum: Octet Exceptions
Topic: 2.27
Replies: 7
Views: 157

Re: 2.27

Radicals only exist when there are an odd number of valence electrons. None of these examples have an odd number so none are radicals
by Jack Riley 4f
Tue Nov 26, 2019 4:16 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Oxidation Number vs. Coordination Number
Replies: 8
Views: 81

Re: Oxidation Number vs. Coordination Number

oxidation number is the charge of the central transition metal ion. Coordination number is the number of bonds the central ion forms in the compound
by Jack Riley 4f
Tue Nov 26, 2019 4:14 pm
Forum: Naming
Topic: Polydentate
Replies: 4
Views: 50

Re: Polydentate

There are 3 nitrogen atoms in that molecule so it can bind on the central ion at 3 binding sites. Thus, it is tridentate
by Jack Riley 4f
Tue Nov 26, 2019 4:12 pm
Forum: Conjugate Acids & Bases
Topic: Acids and Bases
Replies: 10
Views: 82

Re: Acids and Bases

Technically all reactions should have equilibrium arrows. However, for strong acids and bases, the reverse arrow is so small that it is omitted
by Jack Riley 4f
Tue Nov 26, 2019 4:11 pm
Forum: Naming
Topic: polydentate?
Replies: 7
Views: 70

Re: polydentate?

polydentate refers to a ligand that binds to the central ion at more than one binding site.
by Jack Riley 4f
Tue Nov 26, 2019 4:07 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Complexes
Replies: 2
Views: 28

Re: Complexes

Those are the 3 most common shapes that coordinate compounds will take.
by Jack Riley 4f
Tue Nov 19, 2019 12:59 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Square Planar Shape
Replies: 2
Views: 27

Re: Square Planar Shape

Because there are lone pairs on both sides, the effect of both is equal and opposite so the bond angles are just 90 and 180
by Jack Riley 4f
Tue Nov 19, 2019 12:57 pm
Forum: Interionic and Intermolecular Forces (Ion-Ion, Ion-Dipole, Dipole-Dipole, Dipole-Induced Dipole, Dispersion/Induced Dipole-Induced Dipole/London Forces, Hydrogen Bonding)
Topic: Types of forces
Replies: 4
Views: 45

Re: Types of forces

The question only asks about interactions between SO2 and other SO2 molecules. Thus ion-dipole and dipole-induced dipole interactions do not occur.
by Jack Riley 4f
Tue Nov 19, 2019 12:51 pm
Forum: Dipole Moments
Topic: Elongated vs. Spherical Molecules
Replies: 3
Views: 48

Re: Elongated vs. Spherical Molecules

The best way is to look at the structure
by Jack Riley 4f
Tue Nov 19, 2019 12:51 pm
Forum: Dipole Moments
Topic: Polar/Nonpolar Molecule Question
Replies: 2
Views: 33

Re: Polar/Nonpolar Molecule Question

It is polar because it has a bent shape, thus there is a net dipole toward the O atom
by Jack Riley 4f
Tue Nov 19, 2019 12:48 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: interaction potential energy
Replies: 2
Views: 38

Re: interaction potential energy

It is always negative because these interactions are attractive. Ep increases with polarizability and decreases as distance increases.
by Jack Riley 4f
Mon Nov 11, 2019 3:43 pm
Forum: Dipole Moments
Topic: Dipoles
Replies: 3
Views: 28

Re: Dipoles

Dipole moments occur in molecules whose atoms have a high enough difference in electronegativity to create partial positive/negative charges.
by Jack Riley 4f
Mon Nov 11, 2019 3:42 pm
Forum: Dipole Moments
Topic: Dissociation Energies
Replies: 3
Views: 31

Re: Dissociation Energies

Breaking bonds always requires energy while forming bonds releases energy
by Jack Riley 4f
Mon Nov 11, 2019 3:38 pm
Forum: Interionic and Intermolecular Forces (Ion-Ion, Ion-Dipole, Dipole-Dipole, Dipole-Induced Dipole, Dispersion/Induced Dipole-Induced Dipole/London Forces, Hydrogen Bonding)
Topic: london forces
Replies: 6
Views: 44

Re: london forces

Electrons are constantly moving throughout an atom so the random dispersion of these electrons leads to London forces forming between atoms and molecules.
by Jack Riley 4f
Mon Nov 11, 2019 3:37 pm
Forum: Dipole Moments
Topic: Ep Meaning
Replies: 4
Views: 51

Re: Ep Meaning

Ep often stands for energy of photon when doing photoelectric problems and for potential energy when in the context of IMFs
by Jack Riley 4f
Tue Nov 05, 2019 10:37 am
Forum: Heisenberg Indeterminacy (Uncertainty) Equation
Topic: Heisenberg Uncertainty Module Question
Replies: 2
Views: 54

Re: Heisenberg Uncertainty Module Question

You use Heisenberg's Uncertainty Principle which states m(delta v)(delta x) > h/(4pi). Use this to solve for delta v with what you know.
by Jack Riley 4f
Tue Nov 05, 2019 10:35 am
Forum: Resonance Structures
Topic: Drawing Resonance Structures on Test?
Replies: 4
Views: 55

Re: Drawing Resonance Structures on Test?

The charge goes toward the more electronegative atom.
by Jack Riley 4f
Tue Nov 05, 2019 10:29 am
Forum: Lewis Structures
Topic: 2D13
Replies: 4
Views: 52

Re: 2D13

It wouldn't. SO3 would be most stable with 3 double bonds
by Jack Riley 4f
Tue Nov 05, 2019 10:17 am
Forum: Lewis Structures
Topic: 2C.3 Question
Replies: 2
Views: 75

Re: 2C.3 Question

I'm not totally sure, but on the first outline it does say naming is a skill we should be able to do.
by Jack Riley 4f
Tue Nov 05, 2019 10:15 am
Forum: Lewis Structures
Topic: 2B 19 a)
Replies: 1
Views: 43

Re: 2B 19 a)

For a) the O must have the +1 charge because this is the only way both the N and the O can have a full octet. If the N had the +1 charge it would only have 6 valence electrons, not 8.

For c) the same thing applies.
by Jack Riley 4f
Mon Oct 28, 2019 2:01 pm
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: Atomic spectra post assessment question 42
Replies: 2
Views: 53

Re: Atomic spectra post assessment question 42

The above formula is correct and when I calculated it out I got n=6 as my answer. Maybe you just entered it into your calculator wrong
by Jack Riley 4f
Mon Oct 28, 2019 1:56 pm
Forum: Resonance Structures
Topic: Resonance Hybrid
Replies: 3
Views: 42

Re: Resonance Hybrid

resonance hybrids are all the different ways to draw a molecule that has resonance.
by Jack Riley 4f
Mon Oct 28, 2019 1:53 pm
Forum: Ionic & Covalent Bonds
Topic: valence electrons
Replies: 6
Views: 50

Re: valence electrons

manganese has an electron configuration of [Ar] 3d5 4s2 so the electrons in the outermost shell are the 4s2 electrons. This means manganese has 2 valence electrons.
by Jack Riley 4f
Mon Oct 28, 2019 1:50 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: 1E #13
Replies: 3
Views: 68

Re: 1E #13

Dr. Lavelle mentioned this in class, but basically tungsten is an exception to the exception.
by Jack Riley 4f
Mon Oct 28, 2019 1:48 pm
Forum: Ionic & Covalent Bonds
Topic: Delocalized Bond
Replies: 4
Views: 40

Re: Delocalized Bond

Delocalized bonds are bonds that appear in some resonance forms. Basically, it describes the fact that some electrons are not specific to a particular bond or atom. This is due to resonance and is experimentally proven by the fact that all bonds in a molecule with resonance have a length somewhere b...
by Jack Riley 4f
Tue Oct 22, 2019 10:38 am
Forum: Properties of Light
Topic: Homework due Next Week
Replies: 9
Views: 123

Re: Homework due Next Week

The homework for this week just needs to be any 5 different questions from the quantum world sections
by Jack Riley 4f
Tue Oct 22, 2019 10:37 am
Forum: Quantum Numbers and The H-Atom
Topic: orientation of orbitals
Replies: 4
Views: 58

Re: orientation of orbitals

In the p-subshell x, y, and z are used to refer to the 3 different orbitals that exist in this sub shell. Each is oriented along one of the axes, thus they are labeled px, py, pz.
by Jack Riley 4f
Tue Oct 22, 2019 10:34 am
Forum: Quantum Numbers and The H-Atom
Topic: Possible Quantum Number Values
Replies: 4
Views: 47

Re: Possible Quantum Number Values

There are orbitals past f, such as the g orbital for example. However, this orbital is very unstable. For this class, we only need to know how to use the s, p, and d orbitals and know of the f orbital.
by Jack Riley 4f
Tue Oct 22, 2019 10:31 am
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Ground state electron configuration of ions
Replies: 4
Views: 47

Re: Ground state electron configuration of ions

the ground state of an ion or atom simply refers to the lowest energy state of said ion or atom.
by Jack Riley 4f
Tue Oct 22, 2019 10:29 am
Forum: Properties of Light
Topic: Video module test Question-ATOMIC SPECTRA
Replies: 1
Views: 51

Re: Video module test Question-ATOMIC SPECTRA

you must first find the wavelength of krypton-86 radiation. To do this, divide 1 meter by 1650763.73 to find the length of the wavelength. This gives you a wavelength of 6.06x10^-7 or 606 nm. This is visible light. To find the energy we must use E=hv=(hc)/(lambda)=3.28x10^-19
by Jack Riley 4f
Tue Oct 15, 2019 5:09 pm
Forum: Photoelectric Effect
Topic: Photoelectric effect
Replies: 5
Views: 79

Re: Photoelectric effect

Each metal has a specific work function so for all the problems that we will need to know it we will be given it.
by Jack Riley 4f
Tue Oct 15, 2019 5:07 pm
Forum: DeBroglie Equation
Topic: symbol
Replies: 4
Views: 50

Re: symbol

it means proportional to
by Jack Riley 4f
Tue Oct 15, 2019 5:05 pm
Forum: Properties of Light
Topic: Speed of radiation
Replies: 3
Views: 39

Re: Speed of radiation

EM radiation doesn't change speed. Light always travels at 3.0x10^8. This is why the equation c=(lambda)v is viable.
by Jack Riley 4f
Tue Oct 15, 2019 4:58 pm
Forum: Properties of Light
Topic: Need help with 1A.13 homework problem?
Replies: 1
Views: 27

Re: Need help with 1A.13 homework problem?

you use the Rydberg formula with the Constant as 3.29x10^15 because that gives you frequency. After finding the frequency, plug it into c=(lambda)v to find lambda=486 nm. From that, you can check in the table and see it is in the Balmer series and 486 nm is at the higher end of visible light so it i...
by Jack Riley 4f
Tue Oct 15, 2019 4:54 pm
Forum: Properties of Light
Topic: HW Question 1A.15
Replies: 2
Views: 43

Re: HW Question 1A.15

To find n2 you need to use Rydberg's Formula. First you must find frequency using v=c/lambda with lambda=102.6 nm given. Then use Rydberg's formula and solve for n2
by Jack Riley 4f
Wed Oct 09, 2019 4:43 pm
Forum: Properties of Light
Topic: Speed of Light constant
Replies: 7
Views: 52

Re: Speed of Light constant

When he introduced the speed of light in class he used 3.00x10^8 m/s so I think that's what we should use.
by Jack Riley 4f
Wed Oct 09, 2019 4:42 pm
Forum: Photoelectric Effect
Topic: Photon [ENDORSED]
Replies: 6
Views: 114

Re: Photon [ENDORSED]

Photons don't necessarily have "size" as we think about it on a macroscopic scale. They are just packets of energy.
by Jack Riley 4f
Wed Oct 09, 2019 4:34 pm
Forum: Limiting Reactant Calculations
Topic: Need help on question M.9 for chem 14a
Replies: 4
Views: 3075

Re: Need help on question M.9 for chem 14a

To determine if an ion is a spectator ion you just need to look at the product that is stated in the problem. In this problem the product is copper(ii) hydroxide so you know that the sodium and nitrate are the spectators. Because they are spectators, they don't need to be balanced because they exist...
by Jack Riley 4f
Wed Oct 09, 2019 2:55 pm
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: Positive/ Negative regarding E
Replies: 3
Views: 48

Re: Positive/ Negative regarding E

By using E=hv we are finding the frequency of the photon, so we need to worry about the sign of the photon's energy, not the electron's. Because the electron is emitting energy, its sign is negative and so the energy of the photon must be opposite this (positive).
by Jack Riley 4f
Wed Oct 09, 2019 2:43 pm
Forum: Properties of Light
Topic: Classical Mechanics
Replies: 4
Views: 102

Re: Classical Mechanics

light has wavelike properties on a macro scale
by Jack Riley 4f
Mon Sep 30, 2019 10:20 pm
Forum: Accuracy, Precision, Mole, Other Definitions
Topic: Avogadro's Number
Replies: 4
Views: 92

Re: Avogadro's Number

I'm guessing we should go with what professor Lavelle says and follow his lead in using 6.022 instead of 6.0221. Although, I doubt it's significant enough that it will make much of a difference.
by Jack Riley 4f
Mon Sep 30, 2019 10:18 pm
Forum: Molarity, Solutions, Dilutions
Topic: Homework Problem G.17
Replies: 4
Views: 121

Re: Homework Problem G.17

It doesn't matter that they are different substances because the units of each are still in moles. So you need to take into account the molar mass of CuSO4.5H2O instead of just CuSO4.
by Jack Riley 4f
Mon Sep 30, 2019 10:14 pm
Forum: Accuracy, Precision, Mole, Other Definitions
Topic: Formula Units
Replies: 4
Views: 74

Re: Formula Units

"Formula Units" and "Molecules" are basically the same thing. The only difference is that formula units refer to ionic compounds while molecules refer to covalently bonded elements.
by Jack Riley 4f
Mon Sep 30, 2019 10:12 pm
Forum: Accuracy, Precision, Mole, Other Definitions
Topic: Understanding Titrations
Replies: 3
Views: 88

Re: Understanding Titrations

Titration is the process of slowly adding one solution of a known concentration into another solution with a known volume. So basically any of the homework problems that we have completed in fundamentals L is an example of titration.
by Jack Riley 4f
Mon Sep 30, 2019 8:26 pm
Forum: Empirical & Molecular Formulas
Topic: Empirical Formula
Replies: 7
Views: 89

Re: Empirical Formula

You only assume that the sample mass is 100g to make the calculations easier. Because percentages are on a scale of 1-100, assuming that the sample mass is 100g allows you to skip a step and just convert the percentages to masses by changing the units from a percent sign to grams.

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