Search found 108 matches
- Sun Mar 15, 2020 7:32 am
- Forum: Balancing Redox Reactions
- Topic: cathode vs anode
- Replies: 11
- Views: 840
Re: cathode vs anode
Anode is on the left and Cathode on the right
- Sun Mar 15, 2020 7:30 am
- Forum: Student Social/Study Group
- Topic: Tips and advice
- Replies: 1
- Views: 268
Re: Tips and advice
it is really helpful if you write down what you have. For example, like make a somewhat chart and then label what you are trying to find from there you can find an equation which will help you
- Sun Mar 15, 2020 7:29 am
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Enthalpy and Heat
- Replies: 4
- Views: 434
Re: Enthalpy and Heat
Enthalpy is the change in how much heat there is under constant pressure, while heat is the transfer of energy caused by a temp difference
- Sun Mar 15, 2020 7:25 am
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Heat released/ gained
- Replies: 22
- Views: 1057
Re: Heat released/ gained
It takes energy to break bonds and energy is released to form bonds
- Sun Mar 15, 2020 7:24 am
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Midterm 6B
- Replies: 3
- Views: 449
Re: Midterm 6B
I chose a because the states of the reactants and products were similar thus an entropy change will not be too large, which implies a similar delta H and delta G
- Sun Mar 08, 2020 9:26 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: calculating Q
- Replies: 12
- Views: 774
Re: calculating Q
anode/cathode
anode looses mass, cathode gains mass
anode looses mass, cathode gains mass
- Sun Mar 08, 2020 9:25 pm
- Forum: Method of Initial Rates (To Determine n and k)
- Topic: K
- Replies: 11
- Views: 668
Re: K
K is dependent on temperature.
K is not dependent on concentration (equilibirum)
K is not dependent on concentration (equilibirum)
- Sun Mar 08, 2020 9:24 pm
- Forum: Method of Initial Rates (To Determine n and k)
- Topic: K
- Replies: 11
- Views: 668
Re: K
K is dependent on temperature.
REMEMBER it is not dependent on concentration!
REMEMBER it is not dependent on concentration!
- Sun Mar 08, 2020 9:23 pm
- Forum: Student Social/Study Group
- Topic: Final Jitters
- Replies: 457
- Views: 357861
Re: Final Jitters
Sleep!!!
Throughout the week review all the material and the day before just do practice and make sure you are eating and sleeping
Throughout the week review all the material and the day before just do practice and make sure you are eating and sleeping
- Sun Mar 08, 2020 9:22 pm
- Forum: Reaction Mechanisms, Reaction Profiles
- Topic: Exothermic vs. Endothermic
- Replies: 14
- Views: 971
Re: Exothermic vs. Endothermic
An exothermic reaction is one where the reactants have more energy than products. Exothermic releases energy, which is why the reactants should have more energy.
- Sun Mar 08, 2020 9:14 pm
- Forum: General Rate Laws
- Topic: Rate limiting step
- Replies: 12
- Views: 861
Re: Rate limiting step
The rate limiting step is the slow step of the elementary reaction. This step determines the order of a reaction.
- Sun Mar 08, 2020 9:10 pm
- Forum: Kinetics vs. Thermodynamics Controlling a Reaction
- Topic: Molecularity
- Replies: 12
- Views: 830
Re: Molecularity
Molecularity is the number of molecules as a reactant.
For example, N2 + O2 --> 2NO, this is a bimolecular example
For example, N2 + O2 --> 2NO, this is a bimolecular example
- Sun Mar 01, 2020 8:41 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: test 2 topics
- Replies: 11
- Views: 773
Re: test 2 topics
Basically all of electrochemistry and the gibbs free energy portion of thermochem
- Sun Mar 01, 2020 8:37 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: Corrosion
- Replies: 5
- Views: 425
Re: Corrosion
Corrosion is when metals return to their natural oxidation states. It causes a loss in mass, which corresponds to the anode of a galvanic cell. To prevent this, another metal like zinc or chromium is used to prevent the corrosion
- Sun Mar 01, 2020 8:28 pm
- Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
- Topic: delta G=-nFE
- Replies: 7
- Views: 537
Re: delta G=-nFE
You balance the half reactions and find out how many electrons are transferred.
- Sun Mar 01, 2020 8:24 pm
- Forum: Balancing Redox Reactions
- Topic: oxidizing agents
- Replies: 11
- Views: 629
Re: oxidizing agents
The oxidizing agent means that it is oxidizing the thing, it causes the oxidization
- Sun Mar 01, 2020 8:21 pm
- Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
- Topic: when to use K or Q
- Replies: 18
- Views: 1113
Re: when to use K or Q
K is the equilibrium constant and Q is when it is not at equilibrium
- Sun Feb 23, 2020 10:59 pm
- Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
- Topic: STP
- Replies: 13
- Views: 767
Re: STP
Standard Temp: 273 K
Standard Pressure: 1 atm
Standard Pressure: 1 atm
- Sun Feb 23, 2020 10:58 pm
- Forum: Van't Hoff Equation
- Topic: Thermo in Test 2
- Replies: 6
- Views: 452
Re: Thermo in Test 2
Also, review other thermo too because it may be implicitly tested.
- Sun Feb 23, 2020 10:56 pm
- Forum: Balancing Redox Reactions
- Topic: Oxidation?
- Replies: 10
- Views: 702
Re: Oxidation?
Oxidation is the loss of electrons. Think of the element getting more positive.
- Sun Feb 23, 2020 10:54 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Test 2
- Replies: 15
- Views: 922
Re: Test 2
Test 2 covers everything after the midterm. But there might be some questions that connect previous topics to the ones after the midterm.
- Sun Feb 23, 2020 10:50 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Cell Diagrams
- Replies: 9
- Views: 602
Re: Cell Diagrams
Commas means that the state did not change. One line represents state change. Two lines represent the salt bridge.
- Sun Feb 23, 2020 10:50 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: spontaneous reactions
- Replies: 2
- Views: 278
Re: spontaneous reactions
A negative delta S means that the reverse reaction is spontaneous. A positive delta S means that the forward reaction is spontaneous. A negative delta H means that it is exothermic and usually exothermic reactions are associated with being spontaneous because they release energy.
- Sun Feb 23, 2020 10:44 pm
- Forum: General Science Questions
- Topic: test 2
- Replies: 1
- Views: 309
Re: test 2
Finals week is week 11. We have our final about a week or so after.
- Mon Feb 17, 2020 10:37 pm
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: Isolated vs Closed [ENDORSED]
- Replies: 34
- Views: 4294
Re: Isolated vs Closed [ENDORSED]
A closed system can only exchange energy with its surroundings.
An isolated system does not exchange anything.
Open can exchange heat and matter.
Think of a bomb calorimeter as an isolated system and a closed system would be like an open pan on stove, where energy is getting exchanged but not matter
An isolated system does not exchange anything.
Open can exchange heat and matter.
Think of a bomb calorimeter as an isolated system and a closed system would be like an open pan on stove, where energy is getting exchanged but not matter
- Mon Feb 17, 2020 10:30 pm
- Forum: Calculating Work of Expansion
- Topic: Reversible vs Irreversible
- Replies: 13
- Views: 876
Re: Reversible vs Irreversible
For a reversible equation Delta S is equal to -Delta S surr, which means that Delta S total is 0.
For irreversible Delta S is equal to Delta Stotal
For irreversible Delta S is equal to Delta Stotal
- Mon Feb 17, 2020 10:29 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Exothermic rxns being spontaneous
- Replies: 5
- Views: 463
Re: Exothermic rxns being spontaneous
Spontaneous reactions have negative gibbs free energy. G= H-TS (include the deltas). If H is negative (exo) then the likelihood of the overall reaction being negative increases as long as entropy is positive. if entropy is negative then H (-H in this case) must be greater than TS
- Mon Feb 17, 2020 10:26 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Midterm Curve
- Replies: 45
- Views: 2259
Re: Midterm Curve
I have heard that if the midterm/final scores are exceptionally lower than normal, he usually adjusts the grades bit. For 14A the final average was very high thus no curve, but after this midterm there might be one.
- Mon Feb 17, 2020 10:25 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: thermodynamically stable
- Replies: 6
- Views: 447
Re: thermodynamically stable
Thermodynamically stable is equivalent to a negative value for Gibbs. This also means that the rxn is favorable.
- Sun Feb 09, 2020 10:21 pm
- Forum: Entropy Changes Due to Changes in Volume and Temperature
- Topic: The sign of entropy
- Replies: 2
- Views: 196
Re: The sign of entropy
that is a very good question. I think that the sign of entropy is determined by how much disorder there is. If the substance is moving from solid to liquid, entropy is positive and vice versa.
- Sun Feb 09, 2020 10:17 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: q=H
- Replies: 4
- Views: 317
q=H
When does deltaH = q. I remember hearing that q always deltaH, but the reverse is not true? I am unsure if I heard correctly and why this is so/
- Sun Feb 09, 2020 10:13 pm
- Forum: Phase Changes & Related Calculations
- Topic: closed vs isolated
- Replies: 10
- Views: 599
Re: closed vs isolated
An isolated system cannot exchange any energy with its surroundings; however, a closed system can transfer energy (only).
- Sun Feb 09, 2020 10:12 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Favorability of Endothermic Reactions
- Replies: 5
- Views: 227
Re: Favorability of Endothermic Reactions
Endothermic means that there is energy going into the reaction. So if there is an increase of temperature endothermic is favored because the increased heat allows the reaction to favor the products.
- Sun Feb 09, 2020 10:10 pm
- Forum: General Science Questions
- Topic: Midterm Review Questions ?
- Replies: 3
- Views: 288
Re: Midterm Review Questions ?
I would recommend going through each section and there are worked out problems that apply the concepts. This helps better understand the concepts and also find new ways of approaching problems
- Sun Feb 02, 2020 10:09 pm
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: Resources
- Replies: 3
- Views: 131
Resources
Does anyone have any good recommendations for online review materials that explain thermodynamics/thermochemistry well? i.e.) khan academy.
if so can you guys link them below!! thanks!
if so can you guys link them below!! thanks!
- Sun Feb 02, 2020 10:07 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Test 1
- Replies: 6
- Views: 254
Re: Test 1
When Q < K, the forward reaction is favored.
When Q> K, the reverse reaction is favored.
Create a number line if you cannot remember this. if Q is to the left of K then it goes to the right towards K and if Q is to the right of K you go left towards K.
When Q> K, the reverse reaction is favored.
Create a number line if you cannot remember this. if Q is to the left of K then it goes to the right towards K and if Q is to the right of K you go left towards K.
- Sun Feb 02, 2020 10:05 pm
- Forum: Ideal Gases
- Topic: Temperature
- Replies: 17
- Views: 788
Re: Temperature
Kelvin and Celsius increment by the same number, so in certain cases where units cancel out like q=mcdeltt it is valid. In a case where you are not sure, switch to kelvin.
- Sun Feb 02, 2020 10:04 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Hess’ Law
- Replies: 10
- Views: 623
Re: Hess’ Law
Hess's Law uses the enthalpies of intermediary reactions to calculate the total enthalpy. By using Hess's law , you are manipulating reactions to get rid of the intermediary reactants/products and up with the reaction you want. You then factor those manipulations into your calculations for enthalpy.
- Sun Feb 02, 2020 10:02 pm
- Forum: Phase Changes & Related Calculations
- Topic: Pressure in an Open Beaker
- Replies: 10
- Views: 623
Re: Pressure in an Open Beaker
Air pressure is the only pressure acting on the beaker and it does not change. The surroundings encompass a vast area, thus the pressure doesnt change.
- Sun Jan 26, 2020 7:43 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: H2O as a Gas
- Replies: 69
- Views: 6553
Re: H2O as a Gas
Water is not used because it is a liquid. Pretend it is not there
- Sun Jan 26, 2020 7:42 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Hess's Law
- Replies: 9
- Views: 443
Re: Hess's Law
Hess's law basically states that even though there may be intermediary steps in a reaction. The total enthalpy change is the sum of all changes because enthalpy is a state function
- Sun Jan 26, 2020 7:40 pm
- Forum: Amphoteric Compounds
- Topic: Amphoteric vs Amphiprotic
- Replies: 13
- Views: 1523
Re: Amphoteric vs Amphiprotic
Here is another video: https://www.youtube.com/watch?v=zQT6HKplzjY
- Sun Jan 26, 2020 7:38 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Friday Lecture
- Replies: 2
- Views: 150
Re: Friday Lecture
We use the delta H tables to find the standard enthalpies and subract reactants from products. Also remember that O2, N2 and such have values of 0 and are not on the table.
- Sun Jan 26, 2020 7:36 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Using Method 2
- Replies: 2
- Views: 151
Re: Using Method 2
i believe that sometimes we will only be given the individual bond lengths and will have to use method 2.
- Mon Jan 20, 2020 9:57 am
- Forum: Ideal Gases
- Topic: PV=nRT
- Replies: 13
- Views: 700
Re: PV=nRT
If we are tested on this, we will be asked to find the pressure or even concentration and from there calculate the equilibrium constant.
- Mon Jan 20, 2020 9:55 am
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: ice table
- Replies: 5
- Views: 252
Re: ice table
Solids and Liquids do not contribute to the equilibrium constant, thus do not need to be included in ICE tables.
- Mon Jan 20, 2020 9:55 am
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: pKa and pKb
- Replies: 17
- Views: 922
Re: pKa and pKb
Think of Pka and Pkb as being calculated pretty much the same exact way as pH, except in this case you could calculate -log(ka) and ka is the acid dissociation constant used for weak acids.
- Mon Jan 20, 2020 9:53 am
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: X was ignored
- Replies: 27
- Views: 1127
Re: X was ignored
The x is ignored because it is such a small value, thus will not affect the answer extremely. When doing calculations with small x, make sure you do not just plug in 0, but rather emphasize that it is negligible not 0.
- Mon Jan 20, 2020 9:51 am
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Adding Inert Gas
- Replies: 9
- Views: 573
Re: Adding Inert Gas
An inert gas is basically a noble gas. They are nonreactive as their octets are full
- Sun Jan 12, 2020 8:37 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: predicting effects
- Replies: 9
- Views: 444
Re: predicting effects
Removing a product will cause the product concentration to increase because the reaction goes in the forward direction to make up for this product removal
- Sun Jan 12, 2020 8:31 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: K and Q
- Replies: 10
- Views: 312
Re: K and Q
Q is calculated when the reaction is not at equilibrium and K is. K remains the same.
- Sun Jan 12, 2020 8:20 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Inert Gases
- Replies: 4
- Views: 178
Re: Inert Gases
Inert gases are noble gases that have a full octet so they are not that reactive.
- Sun Jan 12, 2020 8:17 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Hw for next week
- Replies: 19
- Views: 803
Re: Hw for next week
I believe that you can do either chemical equilibrium or acid bases. I believe Lavelle said if you have a discussion earlier in the week he doesn't expect you to do the acid and base homework.
- Sun Jan 12, 2020 8:15 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Comparing K Values
- Replies: 4
- Views: 238
Re: Comparing K Values
When K is closer to 1, then that means reactant and product concentrations are the same so that is thermodynamically stable
- Sun Dec 08, 2019 10:28 pm
- Forum: Biological Examples
- Topic: Heme complex & O2
- Replies: 5
- Views: 318
Re: Heme complex & O2
yup one O2 and a histidine to create myoglobin
- Sun Dec 08, 2019 10:27 pm
- Forum: Air Pollution & Acid Rain
- Topic: Carbon dioxide
- Replies: 6
- Views: 735
Re: Carbon dioxide
CO2 increases the concentration of carbonic acid which decreases PH and causes acidosis
- Sun Dec 08, 2019 10:25 pm
- Forum: *Titrations & Titration Calculations
- Topic: Type of Titration
- Replies: 3
- Views: 560
Re: Type of Titration
if the ph is 7 at the equivalence point it represents that a strong acid and strong base titrated together
- Sun Dec 08, 2019 10:23 pm
- Forum: Student Social/Study Group
- Topic: Cyanide
- Replies: 5
- Views: 512
Re: Cyanide
you draw the lewis structure and then subtract the valence electrons from bonds and lone pairs. CN has a triple bond.
- Sun Dec 08, 2019 10:20 pm
- Forum: Heisenberg Indeterminacy (Uncertainty) Equation
- Topic: Uncertainty
- Replies: 5
- Views: 354
Re: Uncertainty
delta x is the uncertainty in the position
- Sun Dec 01, 2019 10:18 pm
- Forum: Lewis Acids & Bases
- Topic: Arrhenius
- Replies: 3
- Views: 224
Re: Arrhenius
I would just know them just in case
- Sun Dec 01, 2019 10:17 pm
- Forum: Bronsted Acids & Bases
- Topic: Naming
- Replies: 4
- Views: 369
Re: Naming
I am honestly not sure
- Sun Dec 01, 2019 10:16 pm
- Forum: Naming
- Topic: -bis, -tris, etc
- Replies: 5
- Views: 453
Re: -bis, -tris, etc
you would use bis tris and etc when the name already has prefixes like bi
- Sun Dec 01, 2019 10:16 pm
- Forum: Amphoteric Compounds
- Topic: 6A.17
- Replies: 5
- Views: 458
Re: 6A.17
Amphoteric compounds are compounds that can react as an acid and base. If you react them with water, there would be 2 reactions. If you write this out then you can tell. Also it is general pattern. There is chart in the textbook which can help.
- Sun Dec 01, 2019 10:13 pm
- Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
- Topic: Final
- Replies: 3
- Views: 450
Re: Final
I feel like the questions would be similarly formatted to the midterm. Reviewing the midterm can help a bit, but be prepared for anything.
- Sun Dec 01, 2019 10:12 pm
- Forum: Naming
- Topic: Water in Coordination Compounds
- Replies: 7
- Views: 599
Re: Water in Coordination Compounds
Usually in coordination compounds, the H20 becomes OH2. Since this is what bonds to the transition metal. I am not sure if we will be penalized for this.
- Sun Nov 24, 2019 10:09 pm
- Forum: Biological Examples
- Topic: Cisplatin
- Replies: 8
- Views: 531
Re: Cisplatin
Cisplatin attacks the dna of the cancer cells and inhibits their repair. Transplatin cannot do that.
- Sun Nov 24, 2019 10:03 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Drawing Structures
- Replies: 4
- Views: 286
Re: Drawing Structures
Yup you can just draw them normally :)
- Sun Nov 24, 2019 9:58 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Coordination Sphere
- Replies: 5
- Views: 424
Re: Coordination Sphere
the first coordiantion sphere is made up of molecules and ions directly attached to the central transition metal
- Sun Nov 24, 2019 9:56 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 3593364
Re: Post All Chemistry Jokes Here
A neutron walks into a bar. He asks the bartender, "How much for a beer?" The bartender gives him a smile and says, "For you, no charge."
- Sun Nov 24, 2019 9:56 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 3593364
Re: Post All Chemistry Jokes Here
Old chemists never die. They just stop reacting!
- Sun Nov 24, 2019 9:54 pm
- Forum: Sigma & Pi Bonds
- Topic: sigma and pi bonds
- Replies: 27
- Views: 1676
Re: sigma and pi bonds
For single bonds there only exists sigma and then for double and triple there are sigma and pi bonds
- Sun Nov 24, 2019 9:52 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Central atom?
- Replies: 5
- Views: 338
Re: Central atom?
Yes it has to be transition metals
- Sun Nov 17, 2019 7:15 pm
- Forum: Sigma & Pi Bonds
- Topic: Sigma vs Pi
- Replies: 11
- Views: 729
Re: Sigma vs Pi
Sigma bonds are found in double triple bonds and Pi bonds are found in single bonds. Sigma are stronger than pi
- Sun Nov 17, 2019 7:12 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Repulsion strength and Bond Angles
- Replies: 12
- Views: 707
Re: Repulsion strength and Bond Angles
The repulsion would be different which will lead to a difference in bond angles
- Sun Nov 17, 2019 7:10 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: Hydrogen Bonding
- Replies: 5
- Views: 293
Re: Hydrogen Bonding
When hydrogen is bonded to N O or F then that is hydrogen bonding
- Sun Nov 17, 2019 7:09 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Lone Pairs
- Replies: 5
- Views: 387
Re: Lone Pairs
Lavelle has gone over bent, trigonal pyramidal, see-saw, and square planar in class
- Sun Nov 17, 2019 7:06 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: VSEPR bond angles
- Replies: 3
- Views: 289
VSEPR bond angles
How do I determine where each bond angle goes?
- Sun Nov 10, 2019 10:02 pm
- Forum: Student Social/Study Group
- Topic: Chem 14B
- Replies: 10
- Views: 760
Chem 14B
Who is taking 14B with Dr.Lavelle next quarter? Anyone taking BL?
- Sun Nov 10, 2019 10:01 pm
- Forum: Student Social/Study Group
- Topic: Study Tips
- Replies: 58
- Views: 4519
Re: Study Tips
What i would recommend doing is reading ur notes from lecture. Then attempting the hw problems for that section. And when u get stuck on a question write down the topics that correspond to it. Review those topics and reattempt the problem. This is a good way to assess your mastery of the material
- Sun Nov 10, 2019 9:57 pm
- Forum: Sigma & Pi Bonds
- Topic: Sigma vs Pi
- Replies: 11
- Views: 729
Re: Sigma vs Pi
Sigma bonds are found in all type of bond. Pi are found in at minimum a double bond.
- Sun Nov 10, 2019 9:47 pm
- Forum: Dipole Moments
- Topic: London Interaction
- Replies: 4
- Views: 169
Re: London Interaction
LDF are also van der waals forces.
- Sun Nov 10, 2019 9:46 pm
- Forum: Dipole Moments
- Topic: Hydrogen Bonding
- Replies: 6
- Views: 440
Re: Hydrogen Bonding
H bonds are the strongest intermolecular force because of the great electronegativity difference between Hydrogen and NOF
- Sat Nov 02, 2019 8:20 pm
- Forum: Properties of Electrons
- Topic: Lewis acids and bases
- Replies: 3
- Views: 272
Re: Lewis acids and bases
lewis acids accept electrons, while lewis bases donate electrons. An example of lewis acid would be H+ and an example of a lewis base would be OH-.
- Sat Nov 02, 2019 8:17 pm
- Forum: Octet Exceptions
- Topic: radicals
- Replies: 3
- Views: 200
Re: radicals
An example of a radical would be OH- since it has 7 electrons
- Sat Nov 02, 2019 8:14 pm
- Forum: Student Social/Study Group
- Topic: Chemical Formulas
- Replies: 3
- Views: 161
Re: Chemical Formulas
I believe that Lavelle said that there might be some that show up as we are slowly learning more and more about naming.
- Sat Nov 02, 2019 8:13 pm
- Forum: Bond Lengths & Energies
- Topic: bond length
- Replies: 6
- Views: 288
Re: bond length
i am not sure, but the usual assumption is that the longer the bond, the weaker the bond.
- Sat Nov 02, 2019 8:08 pm
- Forum: Electronegativity
- Topic: electronegativity
- Replies: 3
- Views: 158
Re: electronegativity
In the midterm, I believe that we only will have a basic periodic table. We should know the trends for electronegativity, electron affinity, ionization energy and such and be able to identify it.
- Sun Oct 27, 2019 7:57 pm
- Forum: Resonance Structures
- Topic: Formal Charge
- Replies: 5
- Views: 256
- Sun Oct 27, 2019 7:56 pm
- Forum: Lewis Structures
- Topic: Choosing the central atom
- Replies: 16
- Views: 784
Re: Choosing the central atom
it is usually the least electronegative atom. Carbon is good
- Sun Oct 27, 2019 7:54 pm
- Forum: Lewis Structures
- Topic: Drawing Lewis Structures
- Replies: 3
- Views: 189
Drawing Lewis Structures
How exactly would you guys recommend drawing a lewis structure
- Sun Oct 27, 2019 7:44 pm
- Forum: Formal Charge and Oxidation Numbers
- Topic: Formal Charge
- Replies: 5
- Views: 356
Re: Formal Charge
A single bond is counted as one electron since it is shared hence the electrons in the equation are divided by 2
- Sun Oct 27, 2019 7:38 pm
- Forum: Trends in The Periodic Table
- Topic: Cations
- Replies: 8
- Views: 365
Re: Cations
Cations lose an electron, which means that their atomic radius is smaller. They oftentimes resemble the element before that which are smaller.
- Sun Oct 20, 2019 4:22 pm
- Forum: Quantum Numbers and The H-Atom
- Topic: Spin States
- Replies: 4
- Views: 197
Re: Spin States
Electrons must have different spin states so they can exist together in the same sublevel.
I'm pretty sure we just need to know how to draw the diagrams. so remember they must be in opposite directions
I'm pretty sure we just need to know how to draw the diagrams. so remember they must be in opposite directions
- Sun Oct 20, 2019 4:16 pm
- Forum: Photoelectric Effect
- Topic: Photoelectric Effect
- Replies: 7
- Views: 322
Re: Photoelectric Effect
Each photon must have enough energy to eject the electron. Increased intensity means that there are more photons. There must be an increased frequency.
- Sun Oct 20, 2019 4:06 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: Orbitals and Quantum Levels
- Replies: 4
- Views: 215
Re: Orbitals and Quantum Levels
After a while, the electron will fall back down to a lower energy level/original one and release this energy in the form of photons. When an electron returns to the ground state, it no longer releases energy.
- Sun Oct 20, 2019 3:54 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Electron Configuration Exceptions
- Replies: 5
- Views: 330
Re: Electron Configuration Exceptions
these exceptions exist because a half-full or completely full d sub-level is more stable than the partially full one.
- Sun Oct 20, 2019 3:51 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Electron Configuration
- Replies: 5
- Views: 231
Re: Electron Configuration
The s shell fills up. Then the p shell fills up. Then d and f if they are applicable. The transition metals are where the d-orbital begins
- Sat Oct 12, 2019 12:41 pm
- Forum: Molarity, Solutions, Dilutions
- Topic: M1V1=M2V2
- Replies: 11
- Views: 86490
Re: M1V1=M2V2
Molarity is moles/liters. if a question asks you to find moles of a certain substance. Then you could break down M1V1=M2V2 into moles/liters*volume.
- Sat Oct 12, 2019 12:36 pm
- Forum: Properties of Electrons
- Topic: Electron After Excited State
- Replies: 7
- Views: 428
Re: Electron After Excited State
When electrons get excited they jump up to a higher energy level and they then release this energy in the form of a photon and eventually fall back to their original state.
- Sat Oct 12, 2019 11:09 am
- Forum: Molarity, Solutions, Dilutions
- Topic: Dilutions
- Replies: 10
- Views: 1085
Re: Dilutions
I would use M1V1=M2V2. I would start by making sure that all my numbers are in the correct units. Then I would plug in all the values that you know. From there I would solve for the unknown. Often times with dilutions you have to read the question carefully. In this case, just make sure that units a...