## Search found 69 matches

Sat Mar 16, 2019 8:14 pm
Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
Topic: Question 14.55
Replies: 1
Views: 252

### Question 14.55

For this question it has 1.0 NiSO4 solution was electrolyzed by using inert electrodes. It asks for the cathode reaction and the anode reaction, and I'm not sure how they chose them.
Sat Mar 16, 2019 7:56 pm
Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
Topic: Question 14.51
Replies: 1
Views: 250

### Question 14.51

For this question it has you analyze a concentration cell of Ag--> Ag+ +e- where the anode has a concentration of .005 mol/L of Ag+ and the cathode has a concentration of .15 mol/L, and it asks what is the maximum work this cell can perform per mole of Ag. I used the Nerst equation and I keep coming...
Fri Mar 15, 2019 9:51 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: 14.17
Replies: 1
Views: 63

### 14.17

For this question it says to find the redox reaction between potassium permanganate and Iron(II) chloride, I used the half reaction Fe2+ + 2e---> Fe, but this is wrong for two reasons. 1. Iron is supposed to be the anode not the cathode and 2. The half reaction involves an Fe3+ species. I have no cl...
Fri Mar 15, 2019 8:25 pm
Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
Topic: 14.55
Replies: 1
Views: 86

### 14.55

How are we supposed to know for this question that the half reactions of NiSO4 are Ni----> Ni2+ and the one involving water? Why isn't the other half reaction involving the sulfate?
Fri Mar 15, 2019 5:55 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: 14.37
Replies: 1
Views: 76

### 14.37

For part A it in the cell diagram it has HCl so I would assume we need a half reaction that involves HCl however I cannot find one in the appendix
Fri Mar 15, 2019 4:46 pm
Forum: First Order Reactions
Topic: 15.37
Replies: 1
Views: 244

### 15.37

For This question I keep getting slightly different answers than whats in the back of the book. For part b I got 801 minutes by seeing that since the halflife was 247 minutes, I found how many half lives there it would take to get to 10% which I found to be 3.25 and I multiplied this by 247. For par...
Fri Mar 15, 2019 3:38 pm
Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
Topic: 14.43
Replies: 1
Views: 77

### 14.43

I have basically no clue on how to do this question, or where to start for that matter.
Fri Mar 15, 2019 1:31 pm
Forum: *Enzyme Kinetics
Topic: How do you tell if something is a catalyst vs an intermediate?
Replies: 16
Views: 913

### How do you tell if something is a catalyst vs an intermediate?

title
Fri Mar 15, 2019 1:24 pm
Forum: Arrhenius Equation, Activation Energies, Catalysts
Topic: 15.67
Replies: 1
Views: 312

### 15.67

For this question we need to use the Arrhenius equation, but I'm unsure on how to use it here. Whenever I divide the first equation by the other I get .98 which is way off.
Tue Feb 26, 2019 6:49 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: question 14.29
Replies: 1
Views: 67

### question 14.29

How are we supposed to know which one will be the reducing agent and the oxidizing agent when both elements are listed in ox/red. Please do not give the answer " the one that is reduced gains electrons," or " the one that is oxidized loses electrons."
Tue Feb 26, 2019 12:50 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Redox couples
Replies: 3
Views: 94

### Re: Redox couples

That is the definition of reduction and oxidation, but doesn't answer my question. When looking at, for example, Ti3+/Ti, and Co2+/Co, how are we supposed to know which one will be the reducing agent and which one will be the oxidizing agent?
Tue Feb 26, 2019 12:34 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Redox couples
Replies: 3
Views: 94

### Redox couples

When looking at a pair of redox couples how are we supposed to know which one is the reducing agent and which one will be the oxidizing agent in the overall reaction?
Tue Feb 26, 2019 9:53 am
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Replies: 2
Views: 89

For questions like 14.15 where it asks to devise a galvanic cell for equations like (H+) + OH- -> H2O, I don't see any reason why the used the equations for the half reactions that they did. In the appendix I see multiple different equations that involve H+ or OH- so how am I supposed to know that I...
Tue Feb 26, 2019 9:50 am
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Replies: 1
Views: 67

In question 14.25 it asks to list the transition metals in order of increasing strength of reducing ability. How are we supposed to know the relative reducing ability for transition metals? I understand the trend for alkali and alkaline earth metals, but I don't see one for the transition metals.
Sat Feb 23, 2019 7:43 pm
Forum: Gibbs Free Energy Concepts and Calculations
Topic: What is the difference between entropy and free energy?
Replies: 2
Views: 226

### What is the difference between entropy and free energy?

title
Sat Feb 23, 2019 7:40 pm
Forum: Calculating Standard Reaction Entropies (e.g. , Using Standard Molar Entropies)
Topic: What is residual entropy?
Replies: 11
Views: 1147

### What is residual entropy?

title
Sat Feb 23, 2019 7:36 pm
Forum: Gibbs Free Energy Concepts and Calculations
Topic: How can a change in entropy be negative?
Replies: 3
Views: 109

### How can a change in entropy be negative?

title
Wed Feb 13, 2019 9:25 am
Forum: Calculating Work of Expansion
Topic: Do we use Pascals or Kilopascals When Finding Work in Joules
Replies: 1
Views: 82

### Do we use Pascals or Kilopascals When Finding Work in Joules

In question 8.3 they use pascals to find it in Joules and then randomly in question 8.9 they decide that kilopascals times the change in volume equals Joules.
Mon Feb 11, 2019 5:30 pm
Forum: Concepts & Calculations Using First Law of Thermodynamics
Topic: Question 8.19
Replies: 2
Views: 104

### Question 8.19

In this question I am multiplying the amount of moles of each substance by the Molar heat capacity and by the change in temperature and I keep coming out with the answer 150 KJ and not 140 KJ and I have no idea what I am doing wrong here.
Mon Feb 11, 2019 5:11 pm
Forum: Calculating Work of Expansion
Topic: Question on the units of work
Replies: 3
Views: 83

### Question on the units of work

In question 8.3 you use the conversion of atm into pascals rather than kilo pascals in the final answer, then is question 8.9 they expect you to use the conversion of atm into kilo pascals for that final answer and now I have no clue which one is correct because using either method is going to make ...
Thu Feb 07, 2019 1:37 pm
Forum: Concepts & Calculations Using First Law of Thermodynamics
Topic: Question 8.45
Replies: 1
Views: 70

### Question 8.45

In part b I have no clue how they got the heat of absorbed, my answer is 368 KJ because you use 4.1 moles of carbon/ 4 moles needed and multiply that by the standard enthalpy.
Thu Feb 07, 2019 1:07 pm
Forum: Concepts & Calculations Using First Law of Thermodynamics
Topic: Question 8.41
Replies: 1
Views: 78

### Question 8.41

For this question I don't know what to do after I found out how many Joules it take for the ice cube to melt. The only equation I can think to do is the specific heat one but that would require me to know the change in temperature which is the point of the question, and considering I don't know by h...
Thu Feb 07, 2019 12:46 pm
Forum: Concepts & Calculations Using First Law of Thermodynamics
Topic: Question 8.31
Replies: 1
Views: 74

### Question 8.31

I'm not sure what equation to use for this question because I don't know the specific molar heat capacity of krypton.
Thu Feb 07, 2019 11:25 am
Forum: Thermodynamic Systems (Open, Closed, Isolated)
Topic: 6th ed 8.9
Replies: 1
Views: 87

### 6th ed 8.9

I keep getting the work done by the system is 148 KJ which is off by a factor of 10^6, what am I doing wrong?
Thu Feb 07, 2019 11:20 am
Forum: Thermodynamic Systems (Open, Closed, Isolated)
Topic: Question 7 Chapter 8 6th edition
Replies: 1
Views: 67

### Question 7 Chapter 8 6th edition

In this question you subtract the heat increased in the system by the heat absorbed to the system, why is this?
Sun Feb 03, 2019 7:19 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: What is pKa and Ka exactly?
Replies: 11
Views: 6031

### What is pKa and Ka exactly?

title
Sun Feb 03, 2019 7:16 pm
Forum: Ideal Gases
Topic: Different Pressure Definition
Replies: 3
Views: 291

### Different Pressure Definition

Could you say J/L instead of bar?
Sun Feb 03, 2019 7:10 pm
Forum: Phase Changes & Related Calculations
Topic: Work
Replies: 2
Views: 100

### Work

What is work exactly?
Sun Jan 27, 2019 10:28 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: ICE Box Ratios
Replies: 8
Views: 421

### Re: ICE Box Ratios

-x is just what you subtract from the initial.
Sun Jan 27, 2019 10:26 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: How Le Chat's Principle is Applied
Replies: 2
Views: 93

### How Le Chat's Principle is Applied

How is Le Chatelier's principle applied when another gas in added to a system?
Sun Jan 27, 2019 10:25 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: When to use Quadratic equation
Replies: 10
Views: 992

### When to use Quadratic equation

When do we have to use the quadratic equation for ice boxes?
Sat Jan 19, 2019 6:13 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Enthalpy of Halogen Breakdown
Replies: 1
Views: 54

### Enthalpy of Halogen Breakdown

Is delta H positive or negative in the breakdown of halogens like F2 into 2F?
Sat Jan 19, 2019 6:11 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Delta H
Replies: 2
Views: 160

### Re: Delta H

H is the amount of energy in a system plus the product of its pressure and volume, so delta H would basically be how much energy was taken away or put into the system. If its positive that means the system absorbed heat and would always favor the products when heat is added and visa versa for your s...
Wed Jan 16, 2019 5:11 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: 11.57 6th edition
Replies: 1
Views: 66

### 11.57 6th edition

I'm not sure what I'm doing wrong on this problem but I keep getting .933 for the Kc and not 3.88.
Sun Jan 13, 2019 1:59 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: ICE table question
Replies: 2
Views: 63

### ICE table question

How do we know to use an ICE table in a question?
Sun Jan 13, 2019 1:58 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Difference between Kc, Kp, and K
Replies: 2
Views: 103

### Difference between Kc, Kp, and K

What is the difference between Kc, Kp, and K (K not referring to the temperature).
Sun Jan 13, 2019 1:55 pm
Forum: Ideal Gases
Topic: How much of Ch.5 are we expected to know?
Replies: 3
Views: 109

### How much of Ch.5 are we expected to know?

Title.
Sun Dec 09, 2018 2:06 pm
Forum: DeBroglie Equation
Topic: Momentum
Replies: 10
Views: 698

### Re: Momentum

You most likely wont be given momentum, but one of the two parts making up momentum, either m or v.
Sun Dec 09, 2018 2:00 pm
Forum: Properties & Structures of Inorganic & Organic Acids
Topic: Why HF is a weaker acid than HCl
Replies: 17
Views: 2667

### Why HF is a weaker acid than HCl

Why is HF a weaker acid than HCl. I understand it has to do with the electronegativity being higher, but if thats the case, why is HClO a stronger acid than HBrO?
Sun Dec 09, 2018 1:57 pm
Forum: Naming
Topic: -ate in naming
Replies: 7
Views: 521

### Re: -ate in naming

You give the central transition metal an -ate ending when it is the anion of the coordination compound.
Sun Dec 09, 2018 1:56 pm
Forum: Naming
Topic: Chloro vs Chlorito
Replies: 10
Views: 523

### Re: Chloro vs Chlorito

I think one of them is just the new naming convention, but I believe we can use either.
Sun Dec 09, 2018 1:55 pm
Forum: Heisenberg Indeterminacy (Uncertainty) Equation
Topic: test 2 question 1 (nitrogen gas molecule)
Replies: 3
Views: 323

### Re: test 2 question 1 (nitrogen gas molecule)

All you have to do is is find the mass of one N2 molecule, multiply it by delta v and dela x which in this case is 1.5E-4m. Then you divide the other side of the equation (h/4pi) by that value and you have delta v.
Sun Dec 09, 2018 1:52 pm
Forum: General Science Questions
Topic: Studying Methods
Replies: 6
Views: 583

### Re: Studying Methods

I usually look at the previous tests and do all of the homework problems.
Sun Dec 09, 2018 1:52 pm
Forum: General Science Questions
Topic: Equations Given on the Final
Replies: 2
Views: 313

### Re: Equations Given on the Final

I think on the midterm it even gave all the acid and base information so I think it'll be the same.
Sat Dec 08, 2018 4:34 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Concept of Chelation
Replies: 3
Views: 126

### Concept of Chelation

Could someone explain the concept of chelation and how to figure out if a molecule is chelating?
Sat Dec 08, 2018 4:28 pm
Forum: Hybridization
Topic: Hybridization of lone pairs.
Replies: 1
Views: 69

### Hybridization of lone pairs.

How do you find what this is?
Fri Dec 07, 2018 5:18 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: How to tell which ligands can be polydentrate
Replies: 4
Views: 162

### How to tell which ligands can be polydentrate

How can you tell which ligands can be polydentrate, and by how much?
Sun Nov 25, 2018 1:23 pm
Forum: Bond Lengths & Energies
Topic: Bonds in Water
Replies: 5
Views: 199

### Re: Bonds in Water

Hydrogen bonds are bonds outside of the molecule itself, so multiple molecules can be hydrogen bonded but still be different molecules. If something is covalently bonded, that results in an entirely different molecule.
Sun Nov 25, 2018 1:21 pm
Forum: Formal Charge and Oxidation Numbers
Topic: Formal charge vs octet rule
Replies: 5
Views: 383

### Re: Formal charge vs octet rule

Only the elements past period 3 can have more than the octet, excluding boron. In those cases it's more important to have the most stable molecule, if it isn't an element in or past period 3, focus on filling the octet.
Sun Nov 25, 2018 1:18 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: Difference in Electronegativity
Replies: 3
Views: 139

### Re: Difference in Electronegativity

You're going to need to need to know which elements result in polar or non polar compounds.
Fri Nov 16, 2018 6:29 pm
Forum: Electronegativity
Topic: Question about what makes something ionic
Replies: 5
Views: 152

### Question about what makes something ionic

When I see HBr I anticipate its going to be ionic because its a large elctronegativity difference. Why am I wrong?
Fri Nov 16, 2018 6:28 pm
Forum: Dipole Moments
Topic: Difference between dipole and london forces?
Replies: 5
Views: 197

### Difference between dipole and london forces?

What is it?
Fri Nov 16, 2018 6:22 pm
Forum: Bond Lengths & Energies
Topic: hydrogen bonds
Replies: 3
Views: 129

### Re: hydrogen bonds

All a melting point is, is vibrating the atoms enough so they can roll past each other, if they're bonded to each other this inhibits their ability to roll past each other.
Fri Nov 09, 2018 10:21 am
Forum: Resonance Structures
Topic: Resonance of Ozone
Replies: 3
Views: 149

### Re: Resonance of Ozone

You just say its one intermediate bond.
Fri Nov 09, 2018 10:11 am
Forum: Ionic & Covalent Bonds
Topic: HW 3.77
Replies: 4
Views: 137

### Re: HW 3.77

Just look up which has a higher and lower electronegativity, and if they have a large difference, it's ionic.
Fri Nov 09, 2018 10:07 am
Forum: Dipole Moments
Topic: London Forces
Replies: 2
Views: 120

### Re: London Forces

It's a result of random movement of electrons, sometimes they just so happen to be more concentrated on one side, this affects electrons in all nearby atoms.
Sun Nov 04, 2018 9:17 am
Forum: Administrative Questions and Class Announcements
Topic: Midterm Location
Replies: 1
Views: 96

### Midterm Location

Where is the midterm going to be held?
Mon Oct 29, 2018 4:40 pm
Forum: Ionic & Covalent Bonds
Topic: Octet Rule Guideline
Replies: 3
Views: 116

### Re: Octet Rule Guideline

It just means valence=how many covalent bonds an atom can make.
Mon Oct 29, 2018 4:38 pm
Forum: Lewis Structures
Topic: 7th Edition 2.B.9
Replies: 5
Views: 98

### Re: 7th Edition 2.B.9

They basically do that in real life. Ionic compounds aren't "molecules" that are bonded together, it's just really intense static.
Mon Oct 29, 2018 4:34 pm
Forum: Lewis Structures
Topic: 3.33 (6th Edition) Part C
Replies: 2
Views: 103

### Re: 3.33 (6th Edition) Part C

Because those electrons aren't involved in the bonding.
Mon Oct 22, 2018 6:01 pm
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: Orientations of Orbitals
Replies: 1
Views: 76

### Re: Orientations of Orbitals

He didn't say anything about so I doubt it, it even said in the book knowing anything past p would be tedious or something along the lines of that.
Mon Oct 22, 2018 5:52 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: The Structure of Many-Electron Atoms 2.37B
Replies: 1
Views: 49

### Re: The Structure of Many-Electron Atoms 2.37B

It said in the chapter that if you evaluate the Schrodinger equation for an s shell, it will have a non-zero probability density in the nucleus because it doesn't have an angular momentum, l, to repel it.
Fri Oct 19, 2018 4:42 pm
Forum: Trends in The Periodic Table
Topic: Transition metal question
Replies: 3
Views: 135

### Transition metal question

Is there a general rule of thumb how many valence electrons transition metals can lose?
Fri Oct 12, 2018 4:03 pm
Forum: Properties of Light
Topic: Diffraction Pattern with Constructive Interference
Replies: 2
Views: 70

### Re: Diffraction Pattern with Constructive Interference

I don't think its due to the fact that it exhibits constructive interference rather than destructive interference specifically, rather it's highlighting the point that it exhibits interference in general which is a wave-like property. The conclusion that it has a wave-particle duality would've been ...
Fri Oct 12, 2018 4:00 pm
Forum: DeBroglie Equation
Topic: Negative Sign
Replies: 4
Views: 124

### Re: Negative Sign

Because it is energy emitted which results in an energy state more negative than when it hadn't emitted a photon.
Fri Oct 12, 2018 12:18 pm
Forum: Properties of Light
Topic: Question 1.3 6th edition
Replies: 2
Views: 114

### Question 1.3 6th edition

How would you tell the extent of change in an electrical field at a given point according to a decrease in frequency?
Thu Oct 04, 2018 7:38 pm
Forum: Accuracy, Precision, Mole, Other Definitions
Topic: E. 15 (7th Edition)
Replies: 2
Views: 94

### Re: E. 15 (7th Edition)

It just arbitrarily asks, find what the mass of the metal sulfide would be, its not related to the previous measurements, but you should be able to find it if you know the mass of sulfide.
Thu Oct 04, 2018 7:34 pm
Forum: Limiting Reactant Calculations
Topic: Defining compounds in equations
Replies: 3
Views: 111

### Re: Defining compounds in equations

He answered this question kind of vaguely, but it seemed like he was saying that you don't need to at this moment. There are also compounds like the osmium one that could be basically anything, and we haven't covered anything pertaining to that anyways.
Thu Oct 04, 2018 7:31 pm
Forum: SI Units, Unit Conversions
Topic: HW E9 in textbook
Replies: 3
Views: 125

### Re: HW E9 in textbook

Yes they can because every molecule has a molar mass that can be calculated, and thus needs to have a number of moles to calculate that.