Search found 111 matches
- Sun Mar 15, 2020 8:33 pm
- Forum: First Order Reactions
- Topic: Pseudo first order
- Replies: 2
- Views: 296
Pseudo first order
When it talks about pseudo first order, second order, etc in the notes and concentrations are changing, how would we solve that? Can someone give me an example? Also can someone explain the reasoning behind the method?
- Sun Mar 15, 2020 8:32 pm
- Forum: Method of Initial Rates (To Determine n and k)
- Topic: Different methods
- Replies: 2
- Views: 360
Different methods
If someone wanted to sum it up,When do use rate law, integrated rate law, and pre equilibrium approaches when dealing with kinetics?
- Sun Mar 15, 2020 8:29 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Seeing how many electrons transfer
- Replies: 3
- Views: 302
Seeing how many electrons transfer
For seeing how many electrons are transferring can u do two ways, separate and find oxidation numbers for a specific atom or just balance each of the equations?
Do both ways work?
Do both ways work?
- Sun Mar 15, 2020 8:28 pm
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: Exothermic reactions
- Replies: 5
- Views: 414
Exothermic reactions
Does decrease temperature increase the rate for an exothermic reaction?
- Sun Mar 15, 2020 8:26 pm
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: Ea, rate, and temperature
- Replies: 4
- Views: 931
Ea, rate, and temperature
How are change of rate, Activation energy, and temperature all related?
Does this matter for endothermic vs exothermic?
This question is regarding the final question on the final?
Does this matter for endothermic vs exothermic?
This question is regarding the final question on the final?
- Sun Mar 08, 2020 11:35 pm
- Forum: Reaction Mechanisms, Reaction Profiles
- Topic: K’
- Replies: 4
- Views: 337
K’
I keep seeing k’ what is that? Is it just a different k? Like k1 and k2?
- Sun Mar 08, 2020 11:33 pm
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: Midterm
- Replies: 2
- Views: 276
Midterm
On one of the questions for the midterm it asked which combination of acid and base would have the biggest change of temperature. I had no clue how to approach this, can someone explain this to me.
- Sun Mar 08, 2020 11:26 pm
- Forum: Interesting Applications: Rechargeable Batteries (Cell Phones, Notebooks, Cars), Fuel Cells (Space Shuttle), Photovoltaic Cells (Solar Panels), Electrolysis, Rust
- Topic: pH
- Replies: 6
- Views: 401
pH
Can someone explain to me how a pH electrode is used and how it has to do with what we are learning?
- Sun Mar 08, 2020 11:24 pm
- Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
- Topic: Finding k1 when given two temperatues
- Replies: 6
- Views: 446
Finding k1 when given two temperatues
When given two temperatures and asked to find one of the K’s, how do we know which temperature is T1 and K1?
Does it matter?
Does it matter?
- Sun Mar 08, 2020 11:22 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: Applying La Chateliers
- Replies: 4
- Views: 285
Applying La Chateliers
In the lecture, Professor Lavelle talked about how You can apply LA chateliers principle to E cell. I didn’t understand it. What happens when you increase one of the reactants? What happens to
The E of cell?
The E of cell?
- Sun Mar 01, 2020 11:46 pm
- Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
- Topic: n in Equation
- Replies: 6
- Views: 436
Re: n in Equation
n is the number of electrons so you would divide the rxn into half rxns and see how many electrons are being transferred and thats your n. In this case it is 2.
- Sun Mar 01, 2020 11:44 pm
- Forum: General Rate Laws
- Topic: class notes
- Replies: 2
- Views: 242
class notes
when Dr. Lavelle said in class that the "slow" stop determine the rate if rxn what did he mean? What is the slow step?
- Sun Mar 01, 2020 11:41 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: Standard E of concentration cell
- Replies: 1
- Views: 137
Standard E of concentration cell
Why is the standard E of a concentration cell always 0? like can someone explain that using the diagram?
- Sun Mar 01, 2020 11:40 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: concentration cell
- Replies: 3
- Views: 244
concentration cell
Does a concentration cell have to have the same things in both its anode and cathode? and does that mean a concentration cell is basically a galvanic cell but with difference concentrations on each sides?
- Sun Mar 01, 2020 11:38 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: at equilibrium
- Replies: 1
- Views: 145
at equilibrium
so basically would we use the Nernst Equation to find the initial Potential when there is a change in concentration however after the run reach equilibrium we know that E cell=0 because change in G=0? Also then would we use the equation to find the K?
- Sun Feb 23, 2020 11:50 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: Nernst Equation usage
- Replies: 6
- Views: 360
Nernst Equation usage
I am still confused on when we would need to use the Nernst Equation? Like what kind of questions would be asked that would prompt us to use the equation?
- Sun Feb 23, 2020 11:47 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: Work and Battery system
- Replies: 6
- Views: 410
Work and Battery system
I still don't understand how A battery system has to do with work? Why is the amount of energy that leaves the system -w? And When does energy leave a battery system?
- Sun Feb 23, 2020 11:45 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: cell potential
- Replies: 3
- Views: 241
cell potential
If the Standard cell potential is an intensive property, then why does concentration affect cell potential using La chatters principle.
- Sun Feb 23, 2020 11:42 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: conducting solids
- Replies: 5
- Views: 326
conducting solids
What are example so conducting solids and not conduction solids? Whats their significant?
- Sun Feb 23, 2020 11:39 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: w max
- Replies: 3
- Views: 357
w max
Can someone explain to me what w(max) is and why they will equal change of G at constant T and P
- Sun Feb 23, 2020 11:16 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: salt bridge
- Replies: 5
- Views: 407
salt bridge
what exactly does the salt bridge do and How does it help neutralize the charge buildup? Also what even causes the charge buildup originally? Can you explain with an example?
- Sun Feb 16, 2020 11:56 pm
- Forum: Concepts & Calculations Using Second Law of Thermodynamics
- Topic: ΔS
- Replies: 1
- Views: 218
Re: ΔS
We would use the the equation qsystem=-q surrounds if we know it’s a reversible process, and use the q of surrounds to find S of surroundings. If it’s irreversible isothermal and no work is and we find that no heat is given of my the system then we know the delta S of surroundings is 0.
- Sun Feb 16, 2020 11:52 pm
- Forum: Ideal Gases
- Topic: When to use equation
- Replies: 9
- Views: 693
When to use equation
Ik that you would use this equation to find a value such as moles when given temp pressure and volume. However, can you use this equation to get the moles of reactant then go to moles of product and then find the concentration of the product using the volume?
- Sun Feb 16, 2020 11:49 pm
- Forum: Entropy Changes Due to Changes in Volume and Temperature
- Topic: Second law of thermodynamics
- Replies: 6
- Views: 462
Second law of thermodynamics
Can someone explain to me the second law of thermodynamics? I know what it says but I’m struggling to understand the concept behind it.
- Sun Feb 16, 2020 11:41 pm
- Forum: Calculating Standard Reaction Entropies (e.g. , Using Standard Molar Entropies)
- Topic: Hc vs Hf
- Replies: 5
- Views: 2598
Hc vs Hf
Is there a difference between Hc and Hf?
Would you use them exactly them say as in products minus reactants?
Would you use them exactly them say as in products minus reactants?
- Sun Feb 16, 2020 11:40 pm
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: Limiting reactant and heat
- Replies: 4
- Views: 547
Limiting reactant and heat
I saw a lot of questions with using limiting react and then finding heat with it, and I don’t understand how a limiting reactant has anything to do with heat? Can someone explain?!
- Sun Feb 16, 2020 11:37 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Ph
- Replies: 8
- Views: 327
Ph
When given the pH, is it always the ph at equilibrium so therefore we can find the h+ at equillibrium?
If not how would it be worded when it refers to initial h+ concentration
If not how would it be worded when it refers to initial h+ concentration
- Mon Feb 10, 2020 12:57 am
- Forum: Phase Changes & Related Calculations
- Topic: delta T
- Replies: 1
- Views: 162
delta T
for delta T is it always Tf-Ti because lets say a copper at 100 degrees celsius were to drop in temperature, is the delta T Tf-100 or 100 -Ti
- Mon Feb 10, 2020 12:19 am
- 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: standard entropy meaning
- Replies: 3
- Views: 188
standard entropy meaning
What is the meaning behind standard entropy? Is it just entropy at a specific temperature?
- Mon Feb 10, 2020 12:16 am
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Entropy of universe
- Replies: 3
- Views: 282
Entropy of universe
Does anyone have an explanation on why it is a spontaneous process if the change in entropy of the universe is +? Why is this favorable.
- Mon Feb 10, 2020 12:11 am
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: identifying systems
- Replies: 3
- Views: 630
identifying systems
I still have difficulties identifying what systems are, will we need to identify systems such as open closed or isolated for the midterm? If so, does anyone have a trick that would be able to help me?
- Mon Feb 10, 2020 12:05 am
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: ideal gas equation.
- Replies: 2
- Views: 159
ideal gas equation.
Can someone explain the equation Utotal= 3/2 nRT. I don't understand where this equation cam from. Also Why does then Delta U equal 0 because delta T is 0. Why is delta T=0.
- Mon Feb 10, 2020 12:02 am
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: 4C.3
- Replies: 1
- Views: 42
4C.3
Hi, 4C.3 says "Calculate the final temperature and the change in enthalpy when 765 J of energy is transferred as heat to 0.820 mol Kr(g) at 298 K and 1.00 atm (a) at constant pressure; (b) at constant vol- ume. Treat the gas as ideal." I get how you have q and you have separate equations f...
- Sun Feb 09, 2020 11:59 pm
- Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
- Topic: irreversible vs reversible
- Replies: 3
- Views: 167
irreversible vs reversible
hi i still don't get the difference between a irreversible and reversible reaction, What are examples of each??
- Sun Feb 09, 2020 11:59 pm
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: constant pressure system
- Replies: 2
- Views: 226
constant pressure system
I still don't get a constant pressure system. Like what is an example of it?
- Sun Feb 09, 2020 11:58 pm
- Forum: Calculating Work of Expansion
- Topic: work done at equilibrium
- Replies: 1
- Views: 136
work done at equilibrium
what is the importance of the equation of the work done at equilibrium? (the integral). Because it still gets you the same equation?
- Sun Feb 02, 2020 11:47 pm
- Forum: Calculating Work of Expansion
- Topic: Area under the curve
- Replies: 3
- Views: 132
Area under the curve
Right before lecture ended, Dr. Lavelle was talking about areas under a curve to measure work and other stuff. What do we have to know about area under a curve because I know that with integrals you are able to measure the area under a curve, but why is that important and do we even have to know that?
- Sun Feb 02, 2020 11:45 pm
- Forum: Calculating Work of Expansion
- Topic: Reversible
- Replies: 7
- Views: 238
Reversible
In the notes, It says since a system is at equilibrium it is a reversible process? What does that mean? What is not a reversible process? What is the importance of it becoming a reversible process?
- Sun Feb 02, 2020 11:35 pm
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: Gases vs liquids and solids
- Replies: 1
- Views: 66
Gases vs liquids and solids
Why are we not able to calculate the change in enthalpy, work, temperature, etc. in liquid and solids? Why is it only gases?
- Sun Feb 02, 2020 11:30 pm
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: q and w
- Replies: 10
- Views: 545
q and w
When reading questions, is there a quick trick we can use to quickly know if we are gonna end up with a positive or negative q and a positive or negative w?
- Sun Feb 02, 2020 11:27 pm
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: Changing energy of systems
- Replies: 1
- Views: 61
Changing energy of systems
I am still confused on the different kinds of systems and how we change energy in each of them. In the notes it says we do work on a system only in a closed system. Why cant we do work on an open system. It also says we only heat or cool a closed system, Why?
- Sun Jan 26, 2020 11:32 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: checking approximation
- Replies: 4
- Views: 115
checking approximation
If the K of reaction is less than 10^-3, but when you check your approximation and it is more than 5%, then does that mean you can't approximate and have to use the quadratic formula?
- Sun Jan 26, 2020 11:29 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Standard enthalpy of formation
- Replies: 1
- Views: 66
Standard enthalpy of formation
If by definition, the standard enthalpy of formation of an element in its most stable form is zero, and the standard enthalpy of 02 is zero, then does that mean Graphite which is the most stable form of C has a standard enthalpy of formation? Also, when will we know when things are in their most sta...
- Sun Jan 26, 2020 11:24 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: pressure and enthalpy
- Replies: 5
- Views: 204
pressure and enthalpy
how exactly is enthalpy affected by pressure?
- Sun Jan 26, 2020 11:21 pm
- Forum: Phase Changes & Related Calculations
- Topic: Temp. of sample
- Replies: 4
- Views: 97
Temp. of sample
What exact did Dr. Lavelle mean when he said because heat is required during melting or boiling, the temp of sample remains constant even though heat is being supplied. Did he mean it stays constant until the transition is complete? Like what is a real life example of this?
- Sun Jan 26, 2020 11:19 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Method 2 example
- Replies: 3
- Views: 94
Method 2 example
In the method 2 example with CH2=Ch2, is the reason he doesn't include the bond enthalpy of the C-H bonds on the reactants side of the equation is because the products side has one more C-H bonds than the reactants side?
- Sun Jan 19, 2020 11:06 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: pKa and pH
- Replies: 1
- Views: 79
Re: pKa and pH
The pH and pka are related in that the lower the pH, the higher the concentration of hydrogen ions, and the the lower the pKa, the stronger the acid and the greater its ability to donate protons. So both can describe a strong acid. However, pH depends on concentrations of the solution, while the pKa...
- Sun Jan 19, 2020 10:58 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: ICE tables for reverse rxns
- Replies: 4
- Views: 213
Re: ICE tables for reverse rxns
You would treat the reverse reaction just how you treated the front reaction. You have initial concentrations and the only difference is that you minus x from the products and add x to the reactants, and then use the equallibrum concentrations and your K to solve for x.
- Sun Jan 19, 2020 10:49 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Approximations
- Replies: 2
- Views: 65
Approximations
Lets say the equilibrium concentration for a reactant is 0.155-x and we can approximate, when we approximate and we get rid of the minus x, do we still include the minus x, when we are asked what the final solution for the reactant?
- Sun Jan 19, 2020 10:46 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Adding a molecule thats not in reaction
- Replies: 2
- Views: 84
Adding a molecule thats not in reaction
Would adding a molecule that is not in the reaction affect the production of products or reactants because there is more pressure in the system?
- Sun Jan 19, 2020 10:38 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: KNO2 and buffers
- Replies: 2
- Views: 1021
KNO2 and buffers
Does NO2- pick up a proton and make the solution basic? How do buffers work? Are they used to neutralize a salt?
- Sun Jan 12, 2020 7:12 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: stoichiometric coefficients
- Replies: 5
- Views: 315
stoichiometric coefficients
how are stoichiometric coefficients involved in Equilibrium? Why when they are the same, its still in equilibrium?
- Sun Jan 12, 2020 7:03 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: "Quick way" part in Lecture
- Replies: 7
- Views: 173
Re: "Quick way" part in Lecture
Yes, what does that mean?
- Sun Jan 12, 2020 6:58 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Inert gas
- Replies: 6
- Views: 143
Inert gas
What is the explanation behind why when inert gas is added and pressure increases, reactant product and volume still stay the same?
- Sun Jan 12, 2020 6:57 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: "Quick way" part in Lecture
- Replies: 7
- Views: 173
"Quick way" part in Lecture
What are examples that can differentiate when it says " V decreases and more moles of gas on left" and "V decreases, and more moles of gas on right"? I was very confused when looking over my notes again.
- Sun Jan 12, 2020 6:56 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: pressure and volume
- Replies: 4
- Views: 120
pressure and volume
How are pressure and volume related, why when you double P that means Volume is halved.
- Sun Jan 12, 2020 6:54 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: increasing yield of NH3
- Replies: 3
- Views: 132
Re: increasing yield of NH3
To increase yield of NH3, you would need to increase the amount of reactants
- Sat Dec 07, 2019 11:27 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Double bond oxygen
- Replies: 1
- Views: 204
Double bond oxygen
Why isn't a oxygen that has lone pairs but is double bonded to something not considered a ligand?
- Sat Dec 07, 2019 11:23 pm
- Forum: Ionic & Covalent Bonds
- Topic: Coulombs equation
- Replies: 2
- Views: 197
Coulombs equation
Can somebody explain Coulombs equation to me? What do the q1 and q2 stand for?
- Sat Dec 07, 2019 11:21 pm
- Forum: Properties & Structures of Inorganic & Organic Acids
- Topic: different acids
- Replies: 1
- Views: 176
different acids
Does anyone know,if for the test we need to know the different formulas for acetic acid, formic acid, and different kinds of acids like that
- Fri Dec 06, 2019 1:08 am
- Forum: Octet Exceptions
- Topic: Incomplete octets
- Replies: 1
- Views: 227
Incomplete octets
Why are incomplete octets formed? Like whats the reasoning behind how they are able to be formed?
- Fri Dec 06, 2019 1:07 am
- Forum: Ionic & Covalent Bonds
- Topic: Coulombs equation
- Replies: 4
- Views: 313
Coulombs equation
Can someone explain coulombs equation to me?
It says F(e)=(kQ1Q2)/r^2
It says F(e)=(kQ1Q2)/r^2
- Fri Dec 06, 2019 1:05 am
- Forum: Properties of Light
- Topic: Light Absorbed/ emitted
- Replies: 4
- Views: 375
Light Absorbed/ emitted
When is light emitted and when is it absorbed. Why was it positive on the midterm when light is absorbed? And What does it mean for light to be emitted or absorbed?
- Sun Dec 01, 2019 11:50 pm
- Forum: Properties & Structures of Inorganic & Organic Acids
- Topic: Lecture
- Replies: 3
- Views: 309
Lecture
Can someone explain to me what Professor Lavelle meant when he said "Resulting anion must be stable, and that oxyacids more readily lose H+ if resulting anion is stabilized by e- withdrawing atoms which decline and stabilize negative charge."
- Sun Dec 01, 2019 11:46 pm
- Forum: Bronsted Acids & Bases
- Topic: Equilibrium Arrows for Strong Acid/Base Equations
- Replies: 1
- Views: 84
Re: Equilibrium Arrows for Strong Acid/Base Equations
During lecture, Professor Lavelle said it would usually be a singe arrow if its a strong acid or base because it is completely dissociating, however if you but the equilibrium arrows it is technically not wrong as long as you explain that it is a strong acid and it is mostly a forward reaction.
- Sun Dec 01, 2019 11:44 pm
- Forum: Polyprotic Acids & Bases
- Topic: Polyprotic acids and bases
- Replies: 2
- Views: 214
Polyprotic acids and bases
Hi, I know this is a dumb question, but what are polyprtoic acids and bases in simple terms. Can you also give examples?
- Sun Dec 01, 2019 11:31 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: TEST 2 POLAR molecule
- Replies: 6
- Views: 404
TEST 2 POLAR molecule
Why is the molecule that shows the lewis structure of CCl2H2 a polar molecule, I thought that the Cl atoms are pulling different ways so it makes the overall molecule non polar? I think the question number was 6.
- Sun Dec 01, 2019 11:26 pm
- Forum: Properties & Structures of Inorganic & Organic Acids
- Topic: Acting as a base
- Replies: 1
- Views: 93
Re: Acting as a base
According to the lewis definition, as long as it has an electron pair to donate it can be considered a base, but there are exceptions such as nobles gases who do have lone pairs but don't act as a base.
- Sun Dec 01, 2019 11:19 pm
- Forum: Properties & Structures of Inorganic & Organic Acids
- Topic: Acid and water
- Replies: 2
- Views: 114
Acid and water
When an Acid combines with water, does it always yield H30+ and when doing pH and your giving the concentration of H30+, do you take the negative log of that to find the pH?
Re: adding O
If thats true then why for his example of [Co(NH3)5Cl]CL.2H2O he said it was Penta Ammine Chloro Cobalt II Chloride DiHydrate. Why is the chloride not Chloro?
- Sun Nov 24, 2019 11:12 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: lecture notes
- Replies: 2
- Views: 109
lecture notes
Can someone explain what Professor Lavelle was talking about when he said that 6 ligands at the corners of an octahedron: octahedral complex. Can someone give me an example of this. Also when eh says 4 ligands at corners of tetrahedron form a tetrahedral complex.
- Sun Nov 24, 2019 11:08 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Coordination complexes
- Replies: 3
- Views: 214
Re: Coordination complexes
A coordination complex is just basically a product of a lewis acid-base reaction where Lewis bases, which are the neutral atoms that have lone pairs to donate to a lewis acid, which are the transition metals. The bonds that they form are coordinate covalent bonds.
- Sun Nov 24, 2019 11:01 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Ligands
- Replies: 4
- Views: 224
Re: Ligands
A ligand is basically an ion or molecule that binds to a central atom that is usually a transition metal to form a coordination complex. The Ligand is the one that has the extra lone pair and is the lone pair donor.
- Sun Nov 24, 2019 3:50 pm
- Forum: Naming
- Topic: Coordination number
- Replies: 7
- Views: 370
Coordination number
I am a bit confused on what determines coordination compound. Can anyone give me an example and explain. Thank you!
- Sun Nov 17, 2019 11:52 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: electronegativity
- Replies: 6
- Views: 367
Re: electronegativity
It goes along the same guidelines as ionization energy. smaller molecule, with a greater nuclear charge, will attracts its electrons more.
- Sun Nov 17, 2019 11:50 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: electronegativity
- Replies: 6
- Views: 367
Re: electronegativity
there is a pattern in the periodic table, as you go up and right, the electronegativity of the atoms rise. But basically, its the how much an atom attracts electrons. And this electronegativity is determined by looking at its atomic number (nuclear charge) and the amount of valence electrons.
- Sun Nov 17, 2019 11:47 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: VSPER
- Replies: 7
- Views: 526
Re: VSPER
An even simpler explanation is that it is basically the shapes of molecules when taking in consideration that electrons have repulsion and that a molecule tries to minimizes this repulsion by arranging its bonds and lone pairs that it has around the central atom. Its basically just a very simple dra...
- Sun Nov 17, 2019 11:37 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: polar vs non polar
- Replies: 6
- Views: 378
polar vs non polar
Can we distinguish a polar molecule between a non polar molecules by just looking at the bonds inside the molecule and see if the there is dipole moments and if they cancel out, or can we just have to know right away by how the structure is drawn?
- Sun Nov 17, 2019 11:32 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: sulfite vs NH3
- Replies: 2
- Views: 98
sulfite vs NH3
Why in the lecture the bond angles for sulfite which has 3 bond pairs and one lone pair, is different than the NH3 which also has 3 bond pairs and 1 lone pair
- Sun Nov 17, 2019 11:31 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Bond Angles
- Replies: 9
- Views: 493
Bond Angles
Will we have to memorize all the bond angles for each of the shapes? If so, does anyone know a quick and easy way because I keep mixing them up?
- Sun Nov 10, 2019 11:44 pm
- Forum: Quantum Numbers and The H-Atom
- Topic: The spin of a quantum number
- Replies: 6
- Views: 504
Re: The spin of a quantum number
If u are asked what spin a certain electron has in its orbital, you won't be able to tell. However, when filling out orbitals, electrons first fill different orbitals and have an up spin, and then after complete the filling of the orbitals with down spin electrons. So you can tell which spin the las...
- Sun Nov 10, 2019 11:39 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: Dipole-Dipole vs Dipole-Induced
- Replies: 2
- Views: 195
Dipole-Dipole vs Dipole-Induced
Whats the difference between Dipole-Dipole forces and Dipole-Induced? Are there similarities also.
- Sun Nov 10, 2019 10:45 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: 3F. 1
- Replies: 1
- Views: 108
Re: 3F. 1
Basically, the different intermolecular forces are london dispersion, hydrogen bonding, and dipole-dipole. For a) there would be hydrogen bonding between two molecules of this because of the H-N Bonds, also there would be dipole-dipole because of the dipole moments of this molecule, and obviously lo...
- Sun Nov 10, 2019 10:38 pm
- Forum: Empirical & Molecular Formulas
- Topic: Midterm question 1
- Replies: 6
- Views: 516
Midterm question 1
Does anyone know how they did question 1, the empirical formula one, on the midterm? I did not know how I was able to take the grams of some of the products and use mole to mole ratio to go to the empirical formula for the reactant.
- Wed Nov 06, 2019 1:52 am
- Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
- Topic: Delta E
- Replies: 1
- Views: 174
Delta E
When Delta E is negative what does that mean? Does that mean that emission vs it being positive which means absorption? Also when an electron is excited to a higher level, does that mean delta E would be positive?
- Sun Nov 03, 2019 11:58 pm
- Forum: Properties of Electrons
- Topic: Molecular spectroscopy
- Replies: 1
- Views: 181
Re: Molecular spectroscopy
They are actually very similar but basically in molecular spectroscopy, it is the study of light by molecules. it is saying that electrons in molecules can be excite to higher energy states. In atomic spec, it is the interactions of this but in atoms, matter that is independent of bonds.
- Sun Nov 03, 2019 11:44 pm
- Forum: Ionic & Covalent Bonds
- Topic: Ionic and Covalent bonds
- Replies: 1
- Views: 77
Ionic and Covalent bonds
Why are ionic compounds made from a metal to a nonmetal and why are covalent bonds made from non-metals only? What is the reasoning? Also, is this rule always true?
- Sun Nov 03, 2019 11:40 pm
- Forum: Octet Exceptions
- Topic: Lewis Acids and Bases?
- Replies: 11
- Views: 495
Lewis Acids and Bases?
Can someone Explain what Lewis Acids and Bases are and why they are an exception to the often rule? Also, what different rxns are they involved in?
- Sun Nov 03, 2019 11:30 pm
- Forum: DeBroglie Equation
- Topic: Dino Nuggets 6a
- Replies: 1
- Views: 143
Dino Nuggets 6a
The question says, "A new element GarBreadium is discovered to have molar mass 3.157 g∙mol-1. The GarBreadium atom travels at an average speed of 1.35x103 m∙s-1 at room temperature. What is the average wavelength of the GarBreadium atom at room temperature?" What is the mass of the atom? a...
- Sun Nov 03, 2019 11:26 pm
- Forum: Octet Exceptions
- Topic: Radicals
- Replies: 5
- Views: 205
Radicals
Why do Radicals happen? Also, What do we have to know about them for our midterm?
- Mon Oct 28, 2019 12:13 am
- Forum: *Shrodinger Equation
- Topic: wave function
- Replies: 3
- Views: 345
wave function
do we need to know the wavefunctions equations, and the potential energy equation? If so can someone explain them to me? and whats their purpose?
- Sun Oct 27, 2019 11:58 pm
- Forum: Photoelectric Effect
- Topic: photoelectric effect book example
- Replies: 2
- Views: 110
photoelectric effect book example
An example in the book in 1B it says You need to make some estimates of the physical properties involved. The speed of an electron emitted from the surface of a sample of potassium by a photon is 668 km?s21. (a) What is the kinetic energy of the ejected electron?, and in the answer in the book it sa...
- Sun Oct 27, 2019 5:02 pm
- Forum: Ionic & Covalent Bonds
- Topic: Ionic v Covalent Bond
- Replies: 3
- Views: 227
Re: Ionic v Covalent Bond
basically every atom has an electronegativity, which is how much an atom attracts electrons. Therefore the reason it says if the electronegativity difference is more than 2 consider it ionic is because at that point the electrons are not being shared anymore and instead one atom takes the electron w...
- Sun Oct 27, 2019 4:56 pm
- Forum: Formal Charge and Oxidation Numbers
- Topic: Formal Charge Vs. Oxidation Number
- Replies: 4
- Views: 260
Re: Formal Charge Vs. Oxidation Number
Basically they are very similar the only big difference is that formal charge assumes all the bonding electrons were divided equally between atoms while in oxidation numbers we assign numbers to the more electronegative atom in the bond.
- Sun Oct 27, 2019 4:52 pm
- Forum: Octet Exceptions
- Topic: Octet rule exception
- Replies: 2
- Views: 114
Octet rule exception
Professor Lavelle was talking about exceptions to the octet rule because they have a d-orbital, does this mean every atom with a d orbital has an exception to the octet rule. Also, do these exceptions affect the drawings of lewis structure so that there are more than 8 electrons around an atom?
- Sun Oct 20, 2019 12:17 pm
- Forum: Quantum Numbers and The H-Atom
- Topic: d orbitals
- Replies: 4
- Views: 135
d orbitals
Why do electrons in the d orbitals have less energy than electrons in the s orbitals such as why does it go 3d^2 4s^2
- Sat Oct 19, 2019 3:57 pm
- Forum: Properties of Electrons
- Topic: Velocity
- Replies: 1
- Views: 81
Velocity
Can someone explain how velocity plays a role in wavelength and electrons as a whole? Like i get the equation but can someone explain the concept behind the equation.
- Sat Oct 19, 2019 3:51 pm
- Forum: Properties of Electrons
- Topic: Balmar and Lyman series
- Replies: 2
- Views: 140
Balmar and Lyman series
For the series I don't understand when the question says N(1)= 2 and N(2)= 3,4 what does the n(1) and N(2) stand for.
- Sat Oct 19, 2019 3:41 pm
- Forum: Properties of Electrons
- Topic: Photo and electron energy
- Replies: 4
- Views: 117
Photo and electron energy
Does the energy difference between to energy levels have to be exact for the energy to be absorbed? Like what happens when the photons energy is more than the energy difference between energy level? Is that where the equation E(excess)= E(photon)-E(energy to remove e-)
- Tue Oct 15, 2019 9:11 pm
- Forum: Properties of Light
- Topic: Defraction patters
- Replies: 3
- Views: 264
Defraction patters
I am a bit confused about diffraction patters and wavelike properties. Do both light and electrons have wave like properties? If so, does that mean they both have Difraction patterns. Also, what are diffraction patters?