Search found 102 matches
- Wed Mar 11, 2020 8:01 am
- Forum: Second Order Reactions
- Topic: Final Exam Equations
- Replies: 10
- Views: 804
Re: Final Exam Equations
Yeah, I'm pretty sure they will be given although there are some derivations that you should know how to use that may not be on the equation sheet. But now that the final is take home this should not be a problem.
- Wed Mar 11, 2020 7:57 am
- Forum: Method of Initial Rates (To Determine n and k)
- Topic: How to determine slow step?
- Replies: 9
- Views: 559
Re: How to determine slow step?
I'm pretty sure the problem will have to tell you if the step is fast or slow. All the practice problems I've done so far have specified.
- Wed Mar 11, 2020 7:54 am
- Forum: Kinetics vs. Thermodynamics Controlling a Reaction
- Topic: intermediate
- Replies: 26
- Views: 2112
Re: intermediate
An intermediate shows up in the products of step one but the reactants of step two and therefore is used up in the second reaction so none will remain after the whole thing is over. The reason this does not affect the rate law is because the rate law is determined by the reactants of the slow step a...
- Wed Mar 11, 2020 7:51 am
- Forum: General Rate Laws
- Topic: Stoichiometric coefficients vs order
- Replies: 4
- Views: 412
Re: Stoichiometric coefficients vs order
The stoichiometric coefficients are equal to the order for the reactants of the rater determining step or the slow step.
- Wed Mar 11, 2020 7:50 am
- Forum: Method of Initial Rates (To Determine n and k)
- Topic: k' vs kr
- Replies: 13
- Views: 863
Re: k' vs kr
k' is just for the reverse reaction and kr is for the forward reaction.
- Tue Mar 03, 2020 11:37 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: cell diagram question
- Replies: 3
- Views: 231
Re: cell diagram question
You use lines when you have a state change an commas when you have a charge change I think.
- Tue Mar 03, 2020 11:36 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: 6L.7b
- Replies: 3
- Views: 303
Re: 6L.7b
Isn't that already balanced?
- Tue Mar 03, 2020 11:34 pm
- Forum: Balancing Redox Reactions
- Topic: Balancing Redox reactions
- Replies: 4
- Views: 478
Re: Balancing Redox reactions
1. balance elements
2. balance oxygens (use h20)
3. balance hydrogens (use H+ for acidic and OH- for basic)
4. balance charge (with electrons)
5. multiply half reactions so the electrons cancel
6. combine half reactions
2. balance oxygens (use h20)
3. balance hydrogens (use H+ for acidic and OH- for basic)
4. balance charge (with electrons)
5. multiply half reactions so the electrons cancel
6. combine half reactions
- Tue Mar 03, 2020 11:32 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Relationship Between Ecell and K
- Replies: 9
- Views: 3387
Re: Relationship Between Ecell and K
I think the higher the value of K, the higher the value of Ecell.
- Tue Mar 03, 2020 11:27 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Galvanic cells
- Replies: 3
- Views: 273
Re: Galvanic cells
Yeah, I think my TA said that the anode should be on the left and the cathode should be on the right. To tell what's being oxidized and reduced I like to write out the skeletal equation and then just work out the half reactions from there.
- Tue Mar 03, 2020 11:25 pm
- Forum: Balancing Redox Reactions
- Topic: adding correct charge
- Replies: 4
- Views: 291
Re: adding correct charge
Make sure you have all of your elements balanced and then make sure you multiply any molecules with a charge by their coefficient and then you should be able to get the right number of electrons.
- Tue Mar 03, 2020 11:23 pm
- Forum: Balancing Redox Reactions
- Topic: Acidic and Basic Redox Reactions
- Replies: 9
- Views: 571
Re: Acidic and Basic Redox Reactions
From what I've seen from the homework problems I think they have to tell us if the solution is in an acidic or basic environment.
- Tue Mar 03, 2020 11:22 pm
- Forum: Balancing Redox Reactions
- Topic: MnO4-
- Replies: 5
- Views: 387
Re: MnO4-
The charge of Mn is 7+ because O has a charge of 2- and there are 4 of them making a total charge of 8-. We are then told that the overall charge of the molecule is 1- so we know that Mn must have a 7+ charge to get the total charge to equal 1-.
- Tue Mar 03, 2020 11:20 pm
- Forum: Balancing Redox Reactions
- Topic: Number of Electrons Being Transferred
- Replies: 5
- Views: 419
Re: Number of Electrons Being Transferred
Balancing the charge of a half reaction is the last step so once you have everything but the charge balanced you should sum up both sides and then add electrons to the side of the reaction that has the more positive charge.
- Tue Mar 03, 2020 11:16 pm
- Forum: Balancing Redox Reactions
- Topic: Balancing half reactions in acidic conditions
- Replies: 8
- Views: 599
Re: Balancing half reactions in acidic conditions
You would just use H+ for acidic conditions.
- Thu Feb 20, 2020 9:48 am
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Spontaneous
- Replies: 23
- Views: 1290
Re: Spontaneous
A reaction will be spontaneous if the Gibbs free energy value is negative. So to find that point you would set the equation to zero to solve and then say that all values less that the one you find will make the reaction spontaneous.
- Thu Feb 20, 2020 9:43 am
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Charge Buildup
- Replies: 3
- Views: 290
Re: Charge Buildup
The electrons flow from the negatively charged anode to the positively charged cathode. So, overtime it makes sense that the electrodes would stop flowing because there would no longer be a difference in charge attracting electrons to either of the sides. Thats why the salt bridge is there, so that ...
- Thu Feb 20, 2020 9:40 am
- Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
- Topic: Standard Enthalpy of Formation
- Replies: 3
- Views: 357
Re: Standard Enthalpy of Formation
You would use the standard enthalpy of formation values when the question is asking for the standard enthalpy. If the question is not asking for standard enthalpy there will usually be other values given so that you can calculate the standard enthalpy in a different method.
- Thu Feb 20, 2020 9:35 am
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Anode
- Replies: 5
- Views: 386
Re: Anode
The Anode must be negative because electrons from the anode flow to the cathode and for this to continue to happen the anode must remain negative. This is made possible from the salt bridge that allows the charge difference to remain constant.
- Thu Feb 20, 2020 9:28 am
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Cell Potential
- Replies: 3
- Views: 296
Re: Cell Potential
I am pretty sure you don't flip the sign because it is already accounted for in the equation. I'm not positive though and I know he went over two different ways to get the same answer and the sign was changed in one of the ways but not the other.
- Thu Feb 13, 2020 10:52 am
- Forum: Calculating Work of Expansion
- Topic: Positive or negative work
- Replies: 15
- Views: 2188
Re: Positive or negative work
if you have a system that work is done on then the work of the system will be positive, if you have a system and work is done by it then work of the system will be negative. I think of it as the system is using energy to do some work on the outside so it is losing that energy.
- Thu Feb 13, 2020 10:50 am
- Forum: Ideal Gases
- Topic: STP
- Replies: 12
- Views: 1653
Re: STP
298 K is 25 C which is room temperature and not standard temperature.
- Thu Feb 13, 2020 10:48 am
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: adiabatic
- Replies: 19
- Views: 1122
Re: adiabatic
Adiabatic means that there was no heat transfer so q=0
- Thu Feb 13, 2020 10:47 am
- Forum: Student Social/Study Group
- Topic: Number of Chemistry Community Posts
- Replies: 45
- Views: 2853
Re: Number of Chemistry Community Posts
Yeah! under quick links click your posts and it should give you a number on the right side at the top of the list.
- Thu Feb 13, 2020 10:44 am
- Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
- Topic: Isobaric systems
- Replies: 16
- Views: 874
Re: Isobaric systems
Isobaric means constant pressure and when you have a system at constant pressure you can say that delta h=q.
- Sun Feb 09, 2020 7:25 pm
- Forum: Entropy Changes Due to Changes in Volume and Temperature
- Topic: Entropy QUestion
- Replies: 2
- Views: 171
Re: Entropy QUestion
Entropy cannot reach equilibrium because it is the disorder of an ever expanding universe which has an increasing disorder so it will never reach equilibrium I think.
- Sun Feb 09, 2020 7:22 pm
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: Thermodynamic system
- Replies: 3
- Views: 222
Re: Thermodynamic system
In an open system both matter and energy can be transferred between the system and the surroundings.
- Sun Feb 09, 2020 7:18 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Cp/Cv
- Replies: 7
- Views: 412
Re: Cp/Cv
You can usually assume constant pressure because usually reactions arn't moved to different pressures throughout the course of the reaction. for example a chemist starting a reaction at sea level will probably let the reaction finish at sea level. This is true for most reactions with engines being a...
- Sun Feb 09, 2020 7:16 pm
- Forum: Phase Changes & Related Calculations
- Topic: Enthalpy of a combustion reaction?
- Replies: 7
- Views: 474
Re: Enthalpy of a combustion reaction?
Usually in a combustion reaction heat is released meaning that delta H will be negative.
- Sun Feb 09, 2020 7:12 pm
- Forum: Phase Changes & Related Calculations
- Topic: -w vs w
- Replies: 15
- Views: 699
Re: -w vs w
When the work is negative that means that work was done by the system but when work is positive that means that the work was done on the system.
- Wed Jan 29, 2020 11:20 pm
- Forum: Calculating Work of Expansion
- Topic: 4A 3
- Replies: 5
- Views: 423
Re: 4A 3
You have the right equation but you need to figure out what delta V is. To do that use delta V= -pi*r^2*d, then plug it into the equation you have and use the pressure given.
- Wed Jan 29, 2020 11:15 pm
- Forum: Calculating Work of Expansion
- Topic: 4A.3
- Replies: 2
- Views: 144
Re: 4A.3
work= -Pext x delta V
delta V= -pi x r^2 x d
use delta V and the pressure given in atm multiploied by the conversion to joules to find the amount of work done.
delta V= -pi x r^2 x d
use delta V and the pressure given in atm multiploied by the conversion to joules to find the amount of work done.
- Wed Jan 29, 2020 11:10 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Standard Subtance
- Replies: 3
- Views: 140
Re: Standard Subtance
The standard state of a substance is the state that the substance is at under the conditions of 1 atmosphere of pressure and 25 degrees celsius.
- Wed Jan 29, 2020 11:09 pm
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: Isolated Systems
- Replies: 5
- Views: 284
Re: Isolated Systems
We can observe the changes within the isolated system, but an isolated system will have no effect on the outside world.
- Wed Jan 29, 2020 11:06 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Celcius and Kelvin
- Replies: 11
- Views: 475
Re: Celcius and Kelvin
I think the conversion from celsius to kelvin is 0 C= 273.15 K, and remembering this is easy but I am also pretty sure it will be provided on the equation sheet on the exam.
- Sat Jan 25, 2020 7:24 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Standard Enthalpy of formation
- Replies: 4
- Views: 238
Re: Standard Enthalpy of formation
I think the SI units for the standard enthalpy of formation is Kj/mol.
- Sat Jan 25, 2020 7:20 pm
- Forum: Phase Changes & Related Calculations
- Topic: Entropy vs Enthalpy
- Replies: 9
- Views: 203
Re: Entropy vs Enthalpy
Great question! I too was confused by this in lecture.
- Sat Jan 25, 2020 7:18 pm
- Forum: General Science Questions
- Topic: Midterms
- Replies: 22
- Views: 1040
Re: Midterms
The first midterm will include everything that we have learned before it, including the things that were on test one. That is at least the way that the midterm for chem 14a with Dr. Lavelle was.
- Sat Jan 25, 2020 7:16 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Excluding H2O from Ka and Kb
- Replies: 5
- Views: 631
Re: Excluding H2O from Ka and Kb
We don't include H2O (l) in our calculations of Ka and Kb because water is going to be present in so much excess in both the reactants and the products that if we plugged it into the equation the two numbers would just cancel each other out.
- Sat Jan 25, 2020 7:15 pm
- Forum: Phase Changes & Related Calculations
- Topic: Endothermic and Exothermic
- Replies: 13
- Views: 659
Re: Endothermic and Exothermic
If the reaction needs heat to be work then you can think of heat being considered as a reactant and therefore the reaction is endothermic because the products are using the heat to form. If the reaction produces heat then you can think of heat as a product and therefore it would an exothermic reacti...
- Sat Jan 25, 2020 7:12 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: enthalpy reaction
- Replies: 4
- Views: 106
Re: enthalpy reaction
We subtract the enthalpy of the products from the reactants when we are calculating enthalpy using bond strengths because forming a bond in the products has a negative enthalpy while breaking one in the reactants has a positive enthalpy.
- Thu Jan 16, 2020 11:45 am
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Factors
- Replies: 7
- Views: 294
Re: Factors
Yes, temperature is the only factor that will change the K equilibrium.
- Thu Jan 16, 2020 11:40 am
- Forum: Ideal Gases
- Topic: bars vs atm
- Replies: 8
- Views: 307
Re: bars vs atm
Both units have to deal with pressure so I think the only thing that matters is that you stay consistent throughout the problem that you are working.
- Thu Jan 16, 2020 11:33 am
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Kw
- Replies: 16
- Views: 470
Re: Kw
Kw is a constant and I believe and it is the equilibrium constant for water and it equals 1.0x10^-14.
- Thu Jan 16, 2020 11:31 am
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Kc vs Kp
- Replies: 5
- Views: 231
Re: Kc vs Kp
I think Kc can be used with both but I think usually the problem will specify whether to find Kc or Kp. :)
- Thu Jan 16, 2020 11:28 am
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Quadratic
- Replies: 10
- Views: 316
Re: Quadratic
I think the chances that you would get two positive values after using the quadratic equation are pretty low but if you do I would plug them back into the ICE table and see which value is more reasonable.
- Thu Jan 09, 2020 12:29 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: units of K
- Replies: 10
- Views: 542
Re: units of K
The equilibrium constant does not have units because they cancel out when you are calculating it.
- Thu Jan 09, 2020 12:27 pm
- Forum: Ideal Gases
- Topic: Solids and Liquids
- Replies: 7
- Views: 463
Re: Solids and Liquids
Solids and liquids are not included because their concentrations stay the same throughout the reaction so there is no need to calculate the change.
- Thu Jan 09, 2020 12:26 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Homework 1
- Replies: 18
- Views: 704
Re: Homework 1
The first homework assignment is due in lecture Friday.
- Thu Jan 09, 2020 12:26 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Homework 1
- Replies: 18
- Views: 704
Re: Homework 1
The first homework assignment is due in lecture Friday.
- Thu Jan 09, 2020 12:25 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: 5G3
- Replies: 8
- Views: 355
Re: 5G3
Yes, you would use H2O because you include all gases in the equation.
- Thu Jan 09, 2020 12:23 pm
- Forum: Ideal Gases
- Topic: K and Q
- Replies: 13
- Views: 404
Re: K and Q
K is the equilibrium constant and is used when the reaction is in equilibrium, Q is the reaction quotient and can be used whether or not the reaction is in equilibrium.
- Tue Dec 03, 2019 10:00 pm
- Forum: Lewis Acids & Bases
- Topic: Naming Acids
- Replies: 3
- Views: 251
Re: Naming Acids
I think that you should probably know the names of common ligands like CN, NH3, PSO4 and such.
- Tue Dec 03, 2019 9:56 pm
- Forum: Bronsted Acids & Bases
- Topic: How to determine whether a molecule is an acid or a base
- Replies: 5
- Views: 336
Re: How to determine whether a molecule is an acid or a base
A lewis definition of a base is a proton donor so N, having a lone pair is likely to give that pair away therefore making it a base.
- Tue Dec 03, 2019 9:47 pm
- Forum: Biological Examples
- Topic: Polydentate
- Replies: 4
- Views: 279
Re: Polydentate
Polydentate describes how many bonding sites a ligand can have to a transition metal.
- Tue Dec 03, 2019 9:45 pm
- Forum: Bronsted Acids & Bases
- Topic: Self-Test J.1A
- Replies: 1
- Views: 208
Re: Self-Test J.1A
C6H6 is probably neither an acid or base because it is stable and nonpolar.
- Tue Dec 03, 2019 9:44 pm
- Forum: Bronsted Acids & Bases
- Topic: CaO
- Replies: 10
- Views: 1580
Re: CaO
Im pretty sure CaO is a strong base because it completely dissociates.
- Sun Dec 01, 2019 3:01 pm
- Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
- Topic: strong or weak base?
- Replies: 13
- Views: 923
Re: strong or weak base?
I think strong acids and bases generally contain elements from groups 1 and 2 on the periodic table.
- Sun Dec 01, 2019 3:00 pm
- Forum: Bronsted Acids & Bases
- Topic: Distinguishing between Strong and Weak Acids/Bases
- Replies: 7
- Views: 487
Re: Distinguishing between Strong and Weak Acids/Bases
I think they're are like 7 strong acids and 8 strong bases so if you memorize those then you should be fine.
- Sun Dec 01, 2019 2:58 pm
- Forum: Naming
- Topic: Final Exam?
- Replies: 20
- Views: 1227
Re: Final Exam?
it is cumulative and I expect he will tell us more in the upcoming classes.
- Sun Dec 01, 2019 2:57 pm
- Forum: Naming
- Topic: Roman Numeral
- Replies: 13
- Views: 976
Re: Roman Numeral
it represents the charge of the element you are dealing with.
- Sun Dec 01, 2019 2:56 pm
- Forum: Conjugate Acids & Bases
- Topic: Water as an Acid/Base
- Replies: 20
- Views: 1612
Re: Water as an Acid/Base
yes, water can either act as an acid or base depending on what it is reacting with.
- Wed Nov 20, 2019 1:40 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Seesaw Shape
- Replies: 12
- Views: 696
Re: Seesaw Shape
Seesaw shape only has >90 and >120 bond angles.
- Wed Nov 20, 2019 1:38 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Class Next Wednesday?
- Replies: 3
- Views: 330
Re: Class Next Wednesday?
I believe so, I'm sure Dr. Lavelle will email if there isn't though.
- Wed Nov 20, 2019 1:37 pm
- Forum: Hybridization
- Topic: Test 2
- Replies: 6
- Views: 390
Re: Test 2
No, test 2 goes up to sigma and pi binds only.
- Wed Nov 20, 2019 1:36 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Do we need to know the pentagonal bipyramidal model for Test 2?
- Replies: 6
- Views: 417
Re: Do we need to know the pentagonal bipyramidal model for Test 2?
Based off the common vsper charts that I have viewed I would say no but it never hurts to know anyway!
- Wed Nov 20, 2019 1:33 pm
- Forum: Hybridization
- Topic: pi bond orientation
- Replies: 4
- Views: 163
Re: pi bond orientation
Pi bonds are rigid because of their orientation around the axis being across it rather that along it therefore not allowing for the movement observed in sigma bonds.
- Sun Nov 17, 2019 5:26 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: linear versus angular
- Replies: 5
- Views: 419
Re: linear versus angular
Yes, it has to do with lone pairs and polarity, so if these charges are present they will repel other elements and cause the bent shape that is observed in water rather than the linear shape present in co2 when there are 2 lone pairs that repel the other elements equally.
- Sun Nov 17, 2019 5:24 pm
- Forum: Student Social/Study Group
- Topic: What will Test 2 be on?
- Replies: 8
- Views: 599
Re: What will Test 2 be on?
The test will cover all the material from the midterm to lecture on Friday including one slide that will be in tomorrows lecture.
- Sun Nov 17, 2019 5:23 pm
- Forum: Hybridization
- Topic: hybridization
- Replies: 1
- Views: 80
Re: hybridization
Hybridization occurs because electrons and are always moving around the central atom and so are the elements that are bonded so any molecule could be in any of its possible shapes at any given time.
- Sun Nov 17, 2019 5:20 pm
- Forum: Student Social/Study Group
- Topic: test 2
- Replies: 8
- Views: 436
Re: test 2
according to the syllabus it is worth 50.
- Sun Nov 17, 2019 5:20 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Bonded and Lone Pairs in VSEPR
- Replies: 4
- Views: 361
Re: Bonded and Lone Pairs in VSEPR
Lone pairs help when determining the general shape but when it comes to molecular shape lone Pairs only influence the shape through repulsion and therefore only bonded atoms effect shape.
- Sun Nov 10, 2019 10:51 pm
- Forum: Formal Charge and Oxidation Numbers
- Topic: Formal Charge and Resonance
- Replies: 5
- Views: 463
Re: Formal Charge and Resonance
No formal charges help find the most stable structure of the compound but don't really tell you anything about resonance.
- Sun Nov 10, 2019 10:50 pm
- Forum: *Liquid Structure (Viscosity, Surface Tension, Liquid Crystals, Ionic Liquids)
- Topic: Viscosity
- Replies: 25
- Views: 3404
Re: Viscosity
The higher the viscosity the smoother the liquid flows so like honey would have lower viscosity than water.
- Sun Nov 10, 2019 10:49 pm
- Forum: Formal Charge and Oxidation Numbers
- Topic: central atom
- Replies: 21
- Views: 1075
Re: central atom
Yes, you always want the most formal charges to be zero in any way that is possible.
- Sun Nov 10, 2019 10:48 pm
- Forum: Hybridization
- Topic: Hybridization Models
- Replies: 4
- Views: 465
Re: Hybridization Models
I think it would be helpful for understanding if you knew how to draw the orbitals.
- Sun Nov 10, 2019 10:47 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 Strength
- Replies: 4
- Views: 291
Re: Interaction Strength
The shape matters with bond strength because the smaller a bond is between two elements the stronger it will be because the effective charge is stronger.
- Sun Nov 03, 2019 3:20 pm
- Forum: Dipole Moments
- Topic: Midterm
- Replies: 8
- Views: 379
Re: Midterm
Yes, Lavelle talked about dipole moments before he said that was the end of the information that was to be present on the test.
- Sun Nov 03, 2019 3:17 pm
- Forum: Lewis Structures
- Topic: Limiting Reactants
- Replies: 3
- Views: 149
Re: Limiting Reactants
Yes, theoretically the amount found in grams should be the same amount present in the products because of the law of conservation of mass.
- Sun Nov 03, 2019 3:13 pm
- Forum: Ionic & Covalent Bonds
- Topic: Electron Configuration
- Replies: 7
- Views: 461
Re: Electron Configuration
Yes, I think the most stable form of an electron is when it has no charge so you will always try and recreate that state for the element or get as close as possible.
- Sun Nov 03, 2019 3:05 pm
- Forum: Formal Charge and Oxidation Numbers
- Topic: Central atom
- Replies: 8
- Views: 370
Re: Central atom
When drawing a lewis structure I think the goal is to have the most elements with a formal charge of zero rather than trying to make the formal charge of the central element zero.
- Sun Nov 03, 2019 3:01 pm
- Forum: Electronegativity
- Topic: What is isoelectronic?
- Replies: 13
- Views: 823
Re: What is isoelectronic?
Isoelectronic means that different ion combinations of the elements have the same number of electrons and therefore the same configuration.
- Tue Oct 29, 2019 11:17 pm
- Forum: Lewis Structures
- Topic: Drawing lewis structures
- Replies: 8
- Views: 307
Re: Drawing lewis structures
I doubt that we need to angle the elements perfectly, I think the main thing is just that you have the configuration with the electrons right.
- Tue Oct 29, 2019 11:12 pm
- Forum: Lewis Structures
- Topic: Lewis Structure structure
- Replies: 4
- Views: 177
Re: Lewis Structure structure
I think this unbalanced slanted structure is due to the fact that some elements have a higher binding affinity to electrons and pull them closer to their nucleus, creating partial charges that still repel other elements a little bit so that the structure is not perfect.
- Tue Oct 29, 2019 11:07 pm
- Forum: Resonance Structures
- Topic: Resonance Clarification
- Replies: 8
- Views: 399
Re: Resonance Clarification
Resonance is basically when there are multiple right lewis configurations to describe a molecule and that not every molecule is going to be fixed in one of the states so resonance is the ability for the correct model for to exist in multiple ways and the molecule can be expected to be in any one of ...
- Tue Oct 29, 2019 11:04 pm
- Forum: Lewis Structures
- Topic: Orbitals
- Replies: 9
- Views: 519
Re: Orbitals
Yeah you would remove the electron from the farthest orbital because it is the farthest distance from the positively charged nucleus and therefore is easiest to remove.
- Tue Oct 29, 2019 10:58 pm
- Forum: Ionic & Covalent Bonds
- Topic: Valence Electrons?
- Replies: 15
- Views: 1068
Re: Valence Electrons?
Valence electrons for the non metals can basically be counted just by going across the periodic table, for example; Li:1, Be:2, B:3, C:4, N:5, O:6, F:7, and Ne:8. And that pattern follows down the columns.
- Sun Oct 20, 2019 9:08 pm
- Forum: Quantum Numbers and The H-Atom
- Topic: Z
- Replies: 5
- Views: 321
Re: Quantum Number Z
The quantum number Z represents the angular component to the momentum of the orbital.
- Sun Oct 20, 2019 9:06 pm
- Forum: Heisenberg Indeterminacy (Uncertainty) Equation
- Topic: Incorrect atomic model example
- Replies: 3
- Views: 150
Re: Incorrect atomic model example
It tells us that the electron cannot be bound to the center of an atom.
- Sun Oct 20, 2019 9:05 pm
- Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
- Topic: Formulas or Experiments
- Replies: 2
- Views: 124
Re: Formulas or Experiments
I think those experiments stand for more of a conceptual understanding of why the calculations that we are doing work.
- Sun Oct 20, 2019 9:04 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Pauli Exclusion Principle
- Replies: 9
- Views: 933
Re: Pauli Exclusion Principle
The Pauli Exclusion Principle states that no one orbital can have more than 2 electrons and that those two electrons cannot have the same quantum number.
- Sun Oct 20, 2019 9:03 pm
- Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
- Topic: When do you use a negative sign in the Bohr equation?
- Replies: 7
- Views: 449
Re: When do you use a negative sign in the Bohr equation?
The negative sign in the Bohr equation is there because it represents the energy the electron must overcome so when the electron and neutron are completely separated, the energy will equal 0.
- Sun Oct 13, 2019 6:50 pm
- Forum: SI Units, Unit Conversions
- Topic: Fundamentals L35
- Replies: 5
- Views: 285
Re: Fundamentals L35
The T stands for tons.
- Sun Oct 13, 2019 6:49 pm
- Forum: Administrative Questions and Class Announcements
- Topic: How to check how many points I have this week for posting on Chemistry Community?
- Replies: 11
- Views: 427
Re: How to check how many points I have this week for posting on Chemistry Community?
Under quick links there is a post that shows your posts so if you have 5 for the week I think you should be good.
- Sun Oct 13, 2019 6:45 pm
- Forum: Photoelectric Effect
- Topic: confirmation.
- Replies: 5
- Views: 227
Re: confirmation.
Yes because the intensity of the light on changes the amplitude of the waves but does not give it enough energy to eject electrons.
- Sun Oct 13, 2019 6:40 pm
- Forum: Properties of Light
- Topic: Next test
- Replies: 23
- Views: 1122
Re: Next test
Yes, I think that we get an equation sheet for every test.
- Sun Oct 13, 2019 6:38 pm
- Forum: Balancing Chemical Reactions
- Topic: Any Easy Way
- Replies: 10
- Views: 620
Re: Any Easy Way
I think the only way to make balancing chemical equations easier is to balance the element that you have the least of first and see how that upsets the balance of other elements and slowly just keep working until the while equation is balanced.
- Fri Oct 04, 2019 1:44 pm
- Forum: Empirical & Molecular Formulas
- Topic: When should one start rounding in a problem?
- Replies: 11
- Views: 611
Re: When should one start rounding in a problem?
you should be as accurate as possible when doing you calculations and then round at the very end to accommodate for sig figs.
- Fri Oct 04, 2019 1:43 pm
- Forum: Significant Figures
- Topic: When to round for sig figs?
- Replies: 12
- Views: 550
Re: When to round for sig figs?
No, you should only round for sig figs the you have your final answer.
- Fri Oct 04, 2019 1:42 pm
- Forum: Balancing Chemical Reactions
- Topic: Combustion
- Replies: 12
- Views: 780
Re: Combustion
Yes, a combustion reaction always results in products of H2O and CO2.