## Search found 36 matches

Wed Mar 13, 2019 8:38 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Cell Diagram Half Reactions
Replies: 1
Views: 68

### Re: Cell Diagram Half Reactions

I think we might be asked to come up with the half reactions
Wed Mar 13, 2019 8:36 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: Calculating the Number of Orientations Mathematically
Replies: 1
Views: 194

### Re: Calculating the Number of Orientations Mathematically

I don't think we would be asked that unless W was a perfect square or something like that... like if you were given W=16 you could say x^n=4^2
Wed Mar 13, 2019 8:33 pm
Forum: Arrhenius Equation, Activation Energies, Catalysts
Topic: example
Replies: 2
Views: 68

### Re: example

I think so
Wed Mar 13, 2019 8:32 pm
Forum: General Rate Laws
Topic: Rate constant units
Replies: 3
Views: 205

### Rate constant units

could someone explain to me how to find the units for the rate constant? Is the unit of the rate always moles per second?
Wed Mar 06, 2019 8:03 pm
Forum: Zero Order Reactions
Topic: Unit for rate constant for zeroth-order reaction
Replies: 2
Views: 76

### Re: Unit for rate constant for zeroth-order reaction

I think because the rate has to be mol.L^-1.s^-1 then the rate constant has to have the same units because it's not multiplied by anything
Mon Feb 25, 2019 10:18 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: MnO4-
Replies: 1
Views: 34

### MnO4-

How do we know the manganese in MnO4- has a charge of +7? Why is the charge of O4 8-?
Sun Feb 03, 2019 2:08 pm
Forum: Phase Changes & Related Calculations
Topic: Steam resulting in burns?
Replies: 6
Views: 126

### Re: Steam resulting in burns?

water vapor burns more than water at 100 degrees celsius (boiling temperature) because a lot of energy is needed to break the intermolecular bonds between the water molecules so that the water is vaporized. This means that when it came in contact with your skin it would release all that extra energy...
Mon Jan 28, 2019 9:26 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: calorimeter
Replies: 2
Views: 60

### Re: calorimeter

I think the whole point of the calorimeter is to have a reaction that doesn't lose energy or matter as it happens, so it basically isolates heat and doesn't release any gases produced in the reaction. I don't understand what the bomb calorimeter is exactly either though.
Mon Jan 28, 2019 9:23 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: When to use which method for calculating reaction enthalpies
Replies: 4
Views: 70

### Re: When to use which method for calculating reaction enthalpies

I think it depends on what values are given in the problem. But also I think Hess's law is more accurate than bond and standard enthalpies so if you can do either I would do Hess's
Mon Jan 28, 2019 9:19 pm
Forum: Calculating Work of Expansion
Topic: value of R?
Replies: 4
Views: 109

### Re: value of R?

R is specific to each gas, it is a constant that is given
Sun Dec 09, 2018 5:42 pm
Forum: Properties of Light
Topic: Number of photons
Replies: 1
Views: 222

### Number of photons

If you are given the energy of a labor and its wavelength how do you calculate the number of photons?
Sat Dec 08, 2018 9:30 pm
Forum: Heisenberg Indeterminacy (Uncertainty) Equation
Topic: heisenberg's
Replies: 5
Views: 346

### Re: heisenberg's

If what you mean is that you can divide or multiply on either side by the same thing then yes
Sat Dec 08, 2018 9:26 pm
Forum: Quantum Numbers and The H-Atom
Topic: Why is this statement incorrect?
Replies: 3
Views: 247

### Re: Why is this statement incorrect?

On the midterm it says for an atom with the quantum number n=9 so this implies l has to be smaller than 9, the lowest ml would be -8
Sat Dec 08, 2018 9:22 pm
Forum: Amphoteric Compounds
Topic: Amphoteric with H+
Replies: 1
Views: 195

### Re: Amphoteric with H+

They work for other molecules as well (if you have a molecule with a Nitrogen with a lone pair and a carboxyl group for example it would be amphiprotic)
Sat Dec 08, 2018 9:19 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: T-shaped structures
Replies: 3
Views: 175

### Re: T-shaped structures

I think it's less than 90
Sat Dec 08, 2018 8:04 pm
Forum: Properties & Structures of Inorganic & Organic Acids
Topic: H+ vs H3O+
Replies: 1
Views: 227

### Re: H+ vs H3O+

I think saying H+(aq) or H3O+ is the same because saying H+ is in aqueous solution means it will bind with H2O molecules to produce H3O+
Sat Dec 08, 2018 7:58 pm
Forum: Properties & Structures of Inorganic & Organic Acids
Topic: pH
Replies: 5
Views: 291

### Re: pH

pH decreases when [H+] increases because H+ is what makes a solution acidic. [H+] increasing is the same as saying [H3O+] is increasing and pH=-log[H3O+]
Sat Dec 08, 2018 7:54 pm
Forum: Sigma & Pi Bonds
Topic: pi and sigma bonds
Replies: 1
Views: 237

### Re: pi and sigma bonds

there would be one sigma and two pi
Fri Dec 07, 2018 7:26 pm
Forum: Hybridization
Topic: Sigma and pi bonds
Replies: 5
Views: 136

### Re: Sigma and pi bonds

I understood that we have to know sigma and pi bonds and hybridization but not the hybridization specific to each bond. So we might have to say the hybridization of an atom but we won't have to know if the bond is C2sp3 or C2p
I'm still not 100% sure
Fri Dec 07, 2018 7:22 pm
Forum: Bond Lengths & Energies
Topic: Double bond lengths
Replies: 2
Views: 252

### Re: Double bond lengths

I think it's because the difference in electronegativity between carbon and oxygen is bigger than that of carbon and carbon or carbon and nitrogen
Fri Dec 07, 2018 7:20 pm
Forum: Bronsted Acids & Bases
Topic: 7th edition 6A.9 Part C
Replies: 1
Views: 106

### Re: 7th edition 6A.9 Part C

I think it's because for it to be considered a proton transfer it really has to be just the proton that changes places and in this case it's rather NH that is substituting the oxygen (which then bonds with the H2 produced)
Thu Dec 06, 2018 7:24 pm
Forum: Acidity & Basicity Constants and The Conjugate Seesaw
Topic: H30+ and H+
Replies: 4
Views: 105

### Re: H30+ and H+

Also you can see it as H3O+ and H+(aq) which are equivalent because H3O+ is just H2O + H+
Tue Nov 27, 2018 4:00 pm
Forum: Administrative Questions and Class Announcements
Topic: Test 3 Content
Replies: 3
Views: 157

### Re: Test 3 Content

So just to be clear the test won’t cover anything from Monday’s lecture? Like coordination compounds?
Tue Nov 27, 2018 3:56 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: Boiling temperatures and hydrogen bonds
Replies: 2
Views: 71

### Boiling temperatures and hydrogen bonds

Can someone explain why H2O has a higher melting and boiling temperature than H2S please? I get that it’s because of hudrogen bonds but wouldn’t H2S have the same hydrogen bonds as H2O has?
Mon Nov 26, 2018 6:10 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Cis and Trans
Replies: 3
Views: 89

### Re: Cis and Trans

Also depending on wether the molecule is Cis or trans affects the way it will react with other molecules
Mon Nov 26, 2018 6:09 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Cis and Trans
Replies: 3
Views: 89

### Re: Cis and Trans

a cis molecule is axially symmetrical and a trans molecule is diagonally symmetrical. If you have a C2Cl2H2 you can have H2C=CCl2 (cis) or HClC=CClH (trans)
Mon Nov 26, 2018 6:05 pm
Forum: Ionic & Covalent Bonds
Topic: Polar Molecule
Replies: 3
Views: 192

### Re: Polar Molecule

not necessarily, because a water molecule is polar even though it is neutral; I think it depends on the electronegativity of the atoms in the molecule
Mon Nov 26, 2018 2:40 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Lone Pairs
Replies: 1
Views: 42

### Re: Lone Pairs

because according to the VSEPR model that molecule is AX3E2 wich is T shape. If it helps think that the central atom has 5 electron density regions so the shape would be trigonal bipyramidal if all 5 were bonds but in this case you replace two of those with lone pairs and it gives yo the T shape.
Mon Nov 26, 2018 2:34 pm
Forum: Sigma & Pi Bonds
Topic: Pi Strength
Replies: 4
Views: 114

### Re: Pi Strength

I'm not certain but I would think that the sigma bond would break first given that the bond is weaker
Tue Nov 20, 2018 1:20 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Bond angles
Replies: 4
Views: 88

### Re: Bond angles

I think it's also important to understand how strong electron repulsion is depending on wether it's a bonding electron or a lone pair electron
Tue Nov 20, 2018 1:17 pm
Forum: Sigma & Pi Bonds
Topic: sigma and pi bonds
Replies: 5
Views: 160

### Re: sigma and pi bonds

sigma bonds are a single bond and pi bonds are a double bond
Tue Nov 20, 2018 1:16 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Hund's rule vs Pauli's
Replies: 3
Views: 298

### Hund's rule vs Pauli's

Could someone rephrase Hund's rule, and explain the difference between Hund's and Pauli's
Sun Nov 04, 2018 7:39 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: cadmium ground state electron configuration
Replies: 2
Views: 146

### cadmium ground state electron configuration

I saw a question that asked what element with a 2+ charge would have this ground state electron configuration:
[Ar]4d10
Mon Oct 22, 2018 11:22 pm
Forum: Trends in The Periodic Table
Topic: Properties of metal
Replies: 1
Views: 86

### Properties of metal

Why are s-block metals typically more reactive than p-block metals?
Sun Oct 21, 2018 7:31 pm
Forum: Administrative Questions and Class Announcements
Topic: Test 2
Replies: 8
Views: 209

### Re: Test 2

I remember the professor saying the test went up to Friday’s lecture. It’s is only on the topics in The Quantum World
Sun Oct 21, 2018 7:27 pm
Forum: Administrative Questions and Class Announcements
Topic: Exam 2
Replies: 4
Views: 157

### Exam 2

Will the equations be given? Such as the Schrödinger’s equation or Heisenberg’s indeterminacy equation?