Search found 80 matches

by Jessica Jones 2B
Sat Mar 17, 2018 3:50 pm
Forum: Reaction Mechanisms, Reaction Profiles
Topic: Drawing Reaction Profiles
Replies: 1
Views: 69

Re: Drawing Reaction Profiles

For the amplitudes it will be based on the activation energy. The slowest step will have the highest activation energy and therefore the highest amplitude. The other steps will be lower and you can not be expected to know which of the remaining ones are higher than the other unless they give us valu...
by Jessica Jones 2B
Sat Mar 17, 2018 3:47 pm
Forum: Arrhenius Equation, Activation Energies, Catalysts
Topic: Question 69
Replies: 1
Views: 160

Re: Question 69

the pre exponential factor is the A, which is the collision frequency. so you would use the equation k= Ae^(-Ea/RT)
by Jessica Jones 2B
Sat Mar 17, 2018 2:03 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: 14.39
Replies: 2
Views: 100

14.39

For this problem do we not have to get the concentrations to have the same units? If not, why?
by Jessica Jones 2B
Sat Mar 17, 2018 2:01 pm
Forum: Entropy Changes Due to Changes in Volume and Temperature
Topic: 9.13
Replies: 2
Views: 188

Re: 9.13

for this equation in terms of temperature you always use Cp or Cv instead of R. All the other ones(Volume and Pressure) are just R.
by Jessica Jones 2B
Sat Mar 17, 2018 1:59 pm
Forum: Phase Changes & Related Calculations
Topic: Test 1, Q7
Replies: 3
Views: 240

Re: Test 1, Q7

and for the mass of the water it will be 1g based on the fact that density= 1g/ml
by Jessica Jones 2B
Sat Mar 17, 2018 1:58 pm
Forum: Phase Changes & Related Calculations
Topic: Test 1, Q7
Replies: 3
Views: 240

Re: Test 1, Q7

you'll want to do qice=-qtea so it would be n*deltaHfus + mCdeltaT = -(mCdeltaT) and substitute in variables to solve for unknown
by Jessica Jones 2B
Sat Mar 17, 2018 1:54 pm
Forum: Concepts & Calculations Using Second Law of Thermodynamics
Topic: delta G
Replies: 1
Views: 171

Re: delta G

deltaG is just the amount of energy available to do work at non standard conditions while deltaG(degree sign) is standard gibbs free energy at 25 degrees and 1 atm.
by Jessica Jones 2B
Sat Mar 17, 2018 1:53 pm
Forum: Arrhenius Equation, Activation Energies, Catalysts
Topic: 15.71
Replies: 1
Views: 68

Re: 15.71

because it is not used up in the reaction. They way I determine which is the catalyst is by seeing if it starts as a reactant in the first step and remains a product in a later step.
Intermediates will usually be formed as a product and then canceled out as a reactant.
by Jessica Jones 2B
Sat Mar 17, 2018 1:51 pm
Forum: Concepts & Calculations Using First Law of Thermodynamics
Topic: First Law Thermo
Replies: 4
Views: 209

Re: First Law Thermo

the first law of thermo is that the internal energy of an isolated system remains constant. From this concept, we get deltaH= q + w. The reason why qsys + qsurr= 0 is because when energy leaves a system, the surroundings gain energy(as energy is never created nor destroyed) and so from this can use ...
by Jessica Jones 2B
Sat Mar 17, 2018 1:47 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Anode and cathode in cell diagram
Replies: 3
Views: 106

Re: Anode and cathode in cell diagram

the one with the highest molarity is always the cathode!
so from this figure out half rxns from the tables and fill it in from there!
by Jessica Jones 2B
Sat Mar 17, 2018 1:45 pm
Forum: General Rate Laws
Topic: Finding the rate constant of Reaction
Replies: 2
Views: 236

Re: Finding the rate constant of Reaction

you would solve for concentration (M= moles/Volume) so do ((grams/g/mol))/Liters). In the problem it should say what order which will decide if you square it or just use that. If it is first order R= k[conc] and second order would be k[con]^2 and then you substitute in values and solve for k.
by Jessica Jones 2B
Fri Mar 16, 2018 2:43 pm
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: Finding E
Replies: 3
Views: 137

Re: Finding E

You should be able to use either. As long as you identify the anode and cathode correctly
by Jessica Jones 2B
Fri Mar 16, 2018 2:39 pm
Forum: Calculating Work of Expansion
Topic: Conversion of R
Replies: 7
Views: 313

Re: Conversion of R

This would depends on the units you are trying to cancel. If pressure were in atm you would use .0826 so that the units would cancel
by Jessica Jones 2B
Fri Mar 16, 2018 2:37 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Bond enthalpies to calculate change in enthalpy
Replies: 3
Views: 184

Re: Bond enthalpies to calculate change in enthalpy

You would use the (deltaH of bonds broken - deltaH of bonds formed). In order to figure out which bonds are broken and formed you look at the lewis structures. You could just break every bond in reactants and from every bond in the products if that is easier for you.
by Jessica Jones 2B
Thu Mar 15, 2018 8:36 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: 8.57
Replies: 1
Views: 143

8.57

For this problem why can't we just do the normal standard potential? Meaning just deltaH=Hproducts- Reactants ?
by Jessica Jones 2B
Thu Mar 15, 2018 8:32 pm
Forum: Arrhenius Equation, Activation Energies, Catalysts
Topic: Reaction profiles
Replies: 1
Views: 92

Reaction profiles

When drawing the reaction profiles how do we know what step would have a higher activation energy(and therefore a larger amplitude) just based on the elementary steps?
by Jessica Jones 2B
Tue Mar 13, 2018 9:30 pm
Forum: Reaction Mechanisms, Reaction Profiles
Topic: Steady State Approximation
Replies: 2
Views: 88

Re: Steady State Approximation

fyi this will not be on the final! only pre-equilibrium approach
by Jessica Jones 2B
Tue Mar 13, 2018 9:29 pm
Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
Topic: Finding Q
Replies: 2
Views: 81

Re: Finding Q

Q is the concentrations when they are not at equilibrium, so you would set it up the same as the equilibrium constant.
by Jessica Jones 2B
Tue Mar 13, 2018 9:26 pm
Forum: Reaction Mechanisms, Reaction Profiles
Topic: Steady state mechanism
Replies: 1
Views: 62

Re: Steady state mechanism

No! we will only use pre equilibrium approach
by Jessica Jones 2B
Wed Mar 07, 2018 2:29 pm
Forum: General Rate Laws
Topic: Rate laws for products vs reactants
Replies: 2
Views: 80

Re: Rate laws for products vs reactants

Yes it would change if you were considering reactants(forward reaction) and then looking at products(reverse reaction). Your rate law would include the elements in either the reactants or products depending on if it is forward or reverse reaction.
by Jessica Jones 2B
Wed Mar 07, 2018 2:24 pm
Forum: *Enzyme Kinetics
Topic: Catalyst
Replies: 6
Views: 357

Re: Catalyst

Yes I thought that was true as well but for problem 5.71, it asks you to figure out which molecule is the catalyst from the equations? How do I do this?
by Jessica Jones 2B
Tue Mar 06, 2018 4:37 pm
Forum: *Enzyme Kinetics
Topic: Catalyst
Replies: 6
Views: 357

Catalyst

How are you able to determine which molecule is the catalyst?
by Jessica Jones 2B
Tue Mar 06, 2018 4:36 pm
Forum: Arrhenius Equation, Activation Energies, Catalysts
Topic: 9.63
Replies: 1
Views: 66

9.63

For this question where did the minus .59 in the solutions manual come from?
by Jessica Jones 2B
Tue Mar 06, 2018 4:35 pm
Forum: Arrhenius Equation, Activation Energies, Catalysts
Topic: 9.61
Replies: 2
Views: 79

9.61

For this problem I am confused why they have 1030K-1000K because the equation is (1/T1)-(1/T2) and this is the opposite of what they did?
by Jessica Jones 2B
Fri Mar 02, 2018 2:50 pm
Forum: Student Social/Study Group
Topic: Post All Chemistry Jokes Here
Replies: 7337
Views: 789146

Re: Post All Chemistry Jokes Here

Advice: Never trust an atom, they make up everything.
by Jessica Jones 2B
Fri Mar 02, 2018 2:49 pm
Forum: Student Social/Study Group
Topic: Post All Chemistry Jokes Here
Replies: 7337
Views: 789146

Re: Post All Chemistry Jokes Here

I told a chemistry joke once, but there was no reaction...
by Jessica Jones 2B
Fri Mar 02, 2018 2:48 pm
Forum: Student Social/Study Group
Topic: Post All Chemistry Jokes Here
Replies: 7337
Views: 789146

Re: Post All Chemistry Jokes Here

Na: "That was sodium funny!"
Ne: "I slapped my neon that one!"
by Jessica Jones 2B
Sun Feb 25, 2018 1:41 pm
Forum: General Rate Laws
Topic: 15.23
Replies: 1
Views: 60

Re: 15.23

Just kidding!! It's an equation :)
by Jessica Jones 2B
Sun Feb 25, 2018 1:38 pm
Forum: General Rate Laws
Topic: 15.23
Replies: 1
Views: 60

15.23

For this problem, I am having trouble understanding where the 0.693 came from in the first step of solutions manual?
by Jessica Jones 2B
Sat Feb 24, 2018 12:57 pm
Forum: Balancing Redox Reactions
Topic: 14.25
Replies: 3
Views: 102

14.25

For this question I understand that you use Appendix 2b cell values to rank them but I'm confused about how you pick which reaction to use. For example, Fe3+---> ... Fe2+--->... etc. These all have different values and change the order of the strongest reducing agent based on which one you choose.
by Jessica Jones 2B
Sat Feb 24, 2018 12:52 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: 14.15c [ENDORSED]
Replies: 3
Views: 96

14.15c [ENDORSED]

Could someone please explain where the KOH came from in the galvanic cell?
by Jessica Jones 2B
Wed Feb 21, 2018 8:52 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Notation
Replies: 2
Views: 101

Notation

I was wondering why sometimes they use ...||Fe3+,Fe| and sometimes they don't use a comma. for example, ...||Au+|Au
In which situations do you use a comma or a line?
by Jessica Jones 2B
Wed Feb 21, 2018 8:42 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Metal on ends of galvanic cell
Replies: 2
Views: 88

Metal on ends of galvanic cell

Will we need to recognize when to put these metals on the ends/ does it matter which metals we pick? Most often seems like Pt
by Jessica Jones 2B
Wed Feb 21, 2018 8:38 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Cathode vs Anode
Replies: 4
Views: 136

Cathode vs Anode

When doing a galvanic cell, how do you know which direction to put the oxidizing and reducing agents? Meaning if the reducing agent was Fe3+ to Fe. Would we write Fe3+|Fe or Fe|Fe3+ ?
by Jessica Jones 2B
Mon Feb 12, 2018 6:45 pm
Forum: Entropy Changes Due to Changes in Volume and Temperature
Topic: 8.33
Replies: 1
Views: 78

8.33

I was under the impression that for a monoatomic gas, C= 3/2 * R, for a diatomic gas, C= 5/2 * R, and for a polyatomic gas, C= 7/2 * R, but in the solution manual polyatomic is 3* R. Could someone explain this?
by Jessica Jones 2B
Mon Feb 12, 2018 6:42 pm
Forum: Gibbs Free Energy Concepts and Calculations
Topic: Gibbs Free Energy
Replies: 1
Views: 75

Gibbs Free Energy

I understand how to calculate and use the equations to find deltaG, but could someone please explain what Gibbs Free Energy means conceptually?
Thank you so much!!
by Jessica Jones 2B
Mon Feb 12, 2018 6:24 pm
Forum: Concepts & Calculations Using First Law of Thermodynamics
Topic: Calculating work and internal energy
Replies: 2
Views: 82

Re: Calculating work and internal energy

Yes w=-pdeltaV is for irreversible work and w=-nRTln(v2/v1) is used for isothermal, reversible expansion.
You would most likely use deltaU= w + q to calculate internal energy and would therefore need to solve for w and for q.
by Jessica Jones 2B
Mon Feb 12, 2018 6:18 pm
Forum: Concepts & Calculations Using Second Law of Thermodynamics
Topic: entropy
Replies: 4
Views: 160

Re: entropy

for reversible reactions, does deltaStot(or universe) always equal 0?
by Jessica Jones 2B
Sun Feb 04, 2018 5:15 pm
Forum: Concepts & Calculations Using Second Law of Thermodynamics
Topic: The sign of the change in Gibb's Free Energy
Replies: 6
Views: 149

Re: The sign of the change in Gibb's Free Energy

This is because a negative G, corresponds to the reaction being spontaneous, and therefore favorable.
by Jessica Jones 2B
Sun Feb 04, 2018 5:13 pm
Forum: Entropy Changes Due to Changes in Volume and Temperature
Topic: deltaS question
Replies: 7
Views: 209

deltaS question

Hi! In the solutions manual I have seen them go back and forth between using deltaS=nCpln(t2/t1) and deltaS=nRln(t2/t1). I am confused on if we are supposed to be using Cp or R? or base it on the problem. Do you only use Cp when doing the (3/2*R) or (5/2*R)?
by Jessica Jones 2B
Sun Feb 04, 2018 4:57 pm
Forum: Entropy Changes Due to Changes in Volume and Temperature
Topic: 9.35?
Replies: 2
Views: 87

Re: 9.35?

there is an error in the solutions manual! check lavelle's list on his website
by Jessica Jones 2B
Sun Jan 28, 2018 5:06 pm
Forum: Calculating Standard Reaction Entropies (e.g. , Using Standard Molar Entropies)
Topic: 9.19
Replies: 2
Views: 106

Re: 9.19

I have similar question because you use the equation deltaS= Cp(ln(T2/T1), but I am confused as to if we are supposed to include the moles/grams in the equation or ignore them all together?
by Jessica Jones 2B
Sun Jan 28, 2018 5:04 pm
Forum: Concepts & Calculations Using Second Law of Thermodynamics
Topic: Entropy based on initial temp
Replies: 3
Views: 73

Re: Entropy based on initial temp

When finding the deltaS for a freezing reaction, would you use -deltaHfusion instead of +deltaHfusion?
by Jessica Jones 2B
Sun Jan 21, 2018 9:32 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: HW 8.57
Replies: 1
Views: 90

Re: HW 8.57

To do this problem, you have to manipulate the coefficients to be able to cancel out and result in the end equation they want. Also keep in mind that when you multiply the equation by a number you also multiply the deltaH value by the same number. Also when you switch the products to reactants, vice...
by Jessica Jones 2B
Sun Jan 21, 2018 9:28 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Question 8.41
Replies: 1
Views: 87

Re: Question 8.41

We do this because you need to account for the phase change as a separate entity and then you also do the q= mCdeltaT for the temperature change and add these energies together. It requires much more energy to create a phase change then just to simply raise the temperature.
by Jessica Jones 2B
Fri Jan 19, 2018 3:05 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: 8.41
Replies: 3
Views: 146

Re: 8.41

You will need to account for the phase change from ice to water, deltaHfusion.
So your q-ice would include both the mCdeltaT and deltaHfusion.
by Jessica Jones 2B
Fri Jan 19, 2018 3:02 pm
Forum: Phase Changes & Related Calculations
Topic: 8.47
Replies: 3
Views: 108

8.47

I am very confused as to why the solutions manual has it as -15kJ + 22 kJ when I would expect it to be -15kJ - 22 kJ?
wouldn't it be (delta U)= (delta H)-(P delta V)?
by Jessica Jones 2B
Mon Jan 15, 2018 8:45 pm
Forum: Concepts & Calculations Using First Law of Thermodynamics
Topic: U = q + w assumptions
Replies: 5
Views: 195

Re: U = q + w assumptions

Do we use different equations for constant pressure and constant volume?
by Jessica Jones 2B
Mon Jan 15, 2018 8:42 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Enthalpy vs Heat
Replies: 2
Views: 141

Re: Enthalpy vs Heat

enthalpy is the amount of heat released or absorbed at a constant pressure. Heat is a form of energy
by Jessica Jones 2B
Mon Jan 15, 2018 8:40 pm
Forum: Phase Changes & Related Calculations
Topic: Signs on energy changes
Replies: 3
Views: 159

Re: Signs on energy changes

yes it would be endothermic!
by Jessica Jones 2B
Sat Dec 09, 2017 1:36 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: equilibrium concentrations increasing, decreasing or remaining constant
Replies: 2
Views: 218

Re: equilibrium concentrations increasing, decreasing or remaining constant

The concentration changing will not change the equilibrium constant because this is a constant. This means that when you increase a certain concentration, the entire reaction will shift to go back to equilibrium. For example A + B = C. If you increase A, B will decrease in order to regain the equili...
by Jessica Jones 2B
Sat Dec 09, 2017 1:30 pm
Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
Topic: 12.33
Replies: 1
Views: 149

Re: 12.33

First you will create the first reaction which is Na2O + H2O ----> 2NaOH, Then you go through the second reaction which is NaOH ----> NA+ + OH-. Based on this reaction you can find the concentration of [OH-] because the pH is 13.25 making pOH 0.75 and the concentration is 10^-.75, which gives you .1...
by Jessica Jones 2B
Sat Dec 09, 2017 1:21 pm
Forum: Bronsted Acids & Bases
Topic: Amphoteric - BeO
Replies: 2
Views: 162

Re: Amphoteric - BeO

There are several exceptions around the metalloids that are also considered amphoteric. These are on page 469 and include Be, Al, Ga, In, Sn, Pb, Bi.
by Jessica Jones 2B
Sat Dec 09, 2017 1:19 pm
Forum: Conjugate Acids & Bases
Topic: Acids and Bases
Replies: 1
Views: 108

Re: Acids and Bases

You should know the strong acids: HCl, HBr, HI, HNO3, HCl3, HCl4, and H2SO4 and the strong bases: NaOH, KOH, RbOH, CsOH, Ca(OH)2, Sr(OH)2, Ba(OH)2
Everything else you should recognize as a weak acid or base.
by Jessica Jones 2B
Wed Dec 06, 2017 2:23 pm
Forum: Acidity & Basicity Constants and The Conjugate Seesaw
Topic: 12.47 [ENDORSED]
Replies: 2
Views: 131

Re: 12.47 [ENDORSED]

Oxidation involves losing e-. This means that when you lose e- you will have a more positive charge, resulting in a greater desire to attract electrons. Because lewis acids accept electrons, this means that the more oxidized, the more acidic it will be.
by Jessica Jones 2B
Tue Dec 05, 2017 10:53 pm
Forum: Properties & Structures of Inorganic & Organic Acids
Topic: Strength of Acids and Bases [ENDORSED]
Replies: 5
Views: 318

Re: Strength of Acids and Bases [ENDORSED]

I understand the ways to determine acid strength (size of atoms,number of oxygens, electronegativity) but how do you determine the strength of a base?
by Jessica Jones 2B
Tue Dec 05, 2017 10:50 pm
Forum: Lewis Acids & Bases
Topic: 12.17
Replies: 1
Views: 122

Re: 12.17

Metals in water form basic oxides
Nonmetals in water form acidic oxides
Metalloids + a few extra ones are amphoteric
Check out page 469 for these exceptions!
by Jessica Jones 2B
Thu Nov 30, 2017 2:00 pm
Forum: Student Social/Study Group
Topic: Naming Complexes
Replies: 6
Views: 911

Re: Naming Complexes

you would also use bis- tris- tetras-, etc if the compound is a polydentate. So you use these prefixes 1. if the name already includes a di, try, etc or 2. if it is a polydentate.
by Jessica Jones 2B
Wed Nov 29, 2017 5:36 pm
Forum: Ideal Gases
Topic: Chemical equilibrium [ENDORSED]
Replies: 9
Views: 687

Re: Chemical equilibrium [ENDORSED]

When solving the ICE box, if you get a equation with x^3 when setting it up equal to Kc, are we expected to be able to solve for x without at calculator?
by Jessica Jones 2B
Sun Nov 26, 2017 7:43 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Problem 11.29
Replies: 2
Views: 104

Re: Problem 11.29

Fyi 29 was not an assigned problem!
by Jessica Jones 2B
Sun Nov 26, 2017 7:43 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: problem11.23
Replies: 2
Views: 118

Re: problem11.23

500.K is referring to the temperature. 500 Kelvin
by Jessica Jones 2B
Sun Nov 19, 2017 8:42 pm
Forum: Naming
Topic: Naming
Replies: 5
Views: 220

Re: Naming

In chapter 17 question 35, why is it trident ate instead of bidentate?
by Jessica Jones 2B
Sun Nov 19, 2017 8:40 pm
Forum: Naming
Topic: Naming
Replies: 5
Views: 220

Re: Naming

When the overall compound is negative, you add an -ate suffix to the central transition metal when naming it.
example [Cr(NH3)2] is just diamminecromium but [Co(NH3)2]^-1 is diamminecromate
by Jessica Jones 2B
Sun Nov 19, 2017 3:04 pm
Forum: Naming
Topic: writing chemical formula based on name
Replies: 4
Views: 137

Re: writing chemical formula based on name

When writing the names, do we use the old name or the new IUPAC name convention?
by Jessica Jones 2B
Wed Nov 15, 2017 5:14 pm
Forum: Bond Lengths & Energies
Topic: Factors that control bond length
Replies: 3
Views: 487

Re: Factors that control bond length

Another factor is if there is a single bond and a double bond, the length of all the bonds is between a single bond and a double bond.
by Jessica Jones 2B
Wed Nov 15, 2017 5:04 pm
Forum: Octet Exceptions
Topic: Why do octets expand?
Replies: 4
Views: 260

Re: Why do octets expand?

All atoms in the 3p and past that like 4p,5p,6p, etc all have access to the d orbitals and can form more bonds than just their expected amount.
by Jessica Jones 2B
Thu Nov 09, 2017 10:06 am
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: Negative Sign in Bohr's Equation
Replies: 3
Views: 1946

Re: Negative Sign in Bohr's Equation

When n=infinity, E=0, and as the energy levels descend, your energy will always be a more negative number.
by Jessica Jones 2B
Thu Nov 09, 2017 10:03 am
Forum: DeBroglie Equation
Topic: DE BROGLIE [ENDORSED]
Replies: 3
Views: 164

Re: DE BROGLIE [ENDORSED]

When using the de broglie for an electron we use the known mass 9.11^-31 kg.
Remember to always use SI units when solving, which are kg.
by Jessica Jones 2B
Tue Oct 31, 2017 11:08 am
Forum: Lewis Structures
Topic: Lewis Structures
Replies: 10
Views: 339

Re: Lewis Structures

When asked for resonance, do you need every single possibility or just a few options?
by Jessica Jones 2B
Tue Oct 31, 2017 11:01 am
Forum: Heisenberg Indeterminacy (Uncertainty) Equation
Topic: Sample Problem (Example 1.7// Textbook)
Replies: 2
Views: 136

Re: Sample Problem (Example 1.7// Textbook)

The 2 come from doubling the uncertainty because it is +/- 1x10^-3. This means that you must add the uncertainty +1.0x10^-3 and -1.0x10^-3(but make this positive for the addition)
by Jessica Jones 2B
Wed Oct 25, 2017 8:39 pm
Forum: Heisenberg Indeterminacy (Uncertainty) Equation
Topic: Exercise 1.45
Replies: 4
Views: 229

Re: Exercise 1.45

The +/- is the indeterminacy of the velocity. You add both the +5 and -5(but keep it positive for the addition) together and your indeterminacy of velocity variable is equal to 10 an you would substitute this in for the variable.
by Jessica Jones 2B
Wed Oct 25, 2017 8:26 pm
Forum: Quantum Numbers and The H-Atom
Topic: Homework Question 2.17 part d
Replies: 5
Views: 251

Re: Homework Question 2.17 part d

When l=3, it corresponds to the f-orbital where there are 14 electrons, 7 orbitals.
l=0 s
l=1 p
l=2 d
l=3 f
by Jessica Jones 2B
Wed Oct 18, 2017 8:15 pm
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: Question 1.15
Replies: 6
Views: 247

Re: Question 1.15

In most problems, it clearly states the order of this change, but if it does not you would use the equation: E= -hR/n^2
Stay away from V= R[1/n1^2 - 1/n2^2] because it will not clearly demonstrate what is truly happening in the problem.
by Jessica Jones 2B
Wed Oct 18, 2017 8:12 pm
Forum: DeBroglie Equation
Topic: Wave vs Particle Properties of Light
Replies: 3
Views: 224

Re: Wave vs Particle Properties of Light

Light has both wave properties and particle properties at all times. Certain experiments proved both of these things. For example, in the photoelectric experiment, the light acted as a particle. On the other hand, we know light has wave like properties based on spectroscopy, which was shown in the e...
by Jessica Jones 2B
Wed Oct 11, 2017 6:16 pm
Forum: Properties of Light
Topic: Rydberg's Formula
Replies: 4
Views: 249

Re: Rydberg's Formula

When do we know to us the ryberg constant 2.178 x10^-18 vs 3.29x 10^15. I understand that the first one is R times planck's constant but I don't understand how to choose which to pick?
by Jessica Jones 2B
Wed Oct 11, 2017 6:10 pm
Forum: Photoelectric Effect
Topic: Energy in kj or j when solving a problem?
Replies: 10
Views: 450

Re: Energy in kj or j when solving a problem?

I have a question regarding units. How do kg cancel out when divided by J?
by Jessica Jones 2B
Wed Oct 11, 2017 6:08 pm
Forum: Properties of Light
Topic: Rydberg's Formula
Replies: 4
Views: 249

Re: Rydberg's Formula

This formula ties into the wavelength series, such as Lyman: n=1, Balmer: n=2, and Pashen: n=3. Your n initial and n final will correlate to these series.
by Jessica Jones 2B
Wed Oct 04, 2017 9:51 pm
Forum: Balancing Chemical Reactions
Topic: Balancing Process
Replies: 11
Views: 399

Re: Balancing Process

When finding the molar mass of a molecule after balancing the equation, do you ignore the stoichiometric coefficients? For example, 4NH3 would you multiply by 4 or just find the molar mass of NH3?
by Jessica Jones 2B
Wed Oct 04, 2017 9:40 pm
Forum: Balancing Chemical Reactions
Topic: Balancing Process
Replies: 11
Views: 399

Re: Balancing Process

For F3 are we going to be expected to know the molecular formula for nitric acid or is this a later topic?

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