Search found 100 matches
- Sat Mar 14, 2020 8:44 pm
- Forum: Reaction Mechanisms, Reaction Profiles
- Topic: are there standard rates of formation?
- Replies: 4
- Views: 369
Re: are there standard rates of formation?
most likely for the test we will be given that information, not required to look it up from a chart ourselves.
- Sat Mar 14, 2020 8:43 pm
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: intensive vs extensive
- Replies: 12
- Views: 775
Re: intensive vs extensive
Extensive: mass dependent
intensive: mass independent
Determines what units or constants you use in equation
intensive: mass independent
Determines what units or constants you use in equation
- Sat Mar 14, 2020 8:38 pm
- Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
- Topic: negative sign
- Replies: 12
- Views: 639
Re: negative sign
When E is positive it is spontaneous, so delta G needs to be negative
- Sat Mar 14, 2020 8:35 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: Qc vs Kc
- Replies: 15
- Views: 5297
Re: Qc vs Kc
When Q and Kc are equal then the reaction has reached equilibrium and Q will stay the same. This doesn't mean that the reaction is no longer occurring rather that both the forward reaction and the reverse reaction are happening at the same rate
- Sat Mar 14, 2020 8:33 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: Qc vs Kc
- Replies: 15
- Views: 5297
Re: Qc vs Kc
Q will tend to go towards Kc, so when Q >Kc it will shift towards the reactants and when Q<Kc it will shift towards the products.
- Sat Mar 14, 2020 3:28 pm
- Forum: Entropy Changes Due to Changes in Volume and Temperature
- Topic: Delta S
- Replies: 8
- Views: 715
Re: Delta S
Ssys + Ssurr = Stot
same thing applies when you make them all delta
same thing applies when you make them all delta
- Sat Mar 14, 2020 2:52 pm
- Forum: Zero Order Reactions
- Topic: 0 order
- Replies: 6
- Views: 490
Re: 0 order
concentration of reactants does not affect rate.
- Sat Mar 14, 2020 2:51 pm
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: heterogeneous catalyst
- Replies: 4
- Views: 318
Re: heterogeneous catalyst
Most heterogeneous catalysts are solids, and in order to maximize catalyst-substrate interaction it needs to be porous or finely divided.
- Sat Mar 14, 2020 2:28 pm
- Forum: First Order Reactions
- Topic: Linear versus Non-Linear
- Replies: 3
- Views: 363
Re: Linear versus Non-Linear
The linear form is useful for graphical analysis and basic comprehension. It can also be useful for finding k, because its the slope of the line. Either work for simple calculation using the relationship between time and concentration of the reactant.
- Sat Mar 14, 2020 2:21 pm
- Forum: Balancing Redox Reactions
- Topic: Acid or base?
- Replies: 5
- Views: 497
Re: Acid or base?
It will be given, but you might have to do some Ka pKa manipulation to find out, so make sure you remember how
- Sat Mar 14, 2020 2:18 pm
- Forum: Reaction Mechanisms, Reaction Profiles
- Topic: Mechanisms
- Replies: 3
- Views: 299
Re: Mechanisms
With the reaction mechanisms method we can make educated guesses on reaction rates for untried reactions with the same or similar steps.
- Sat Mar 14, 2020 2:09 pm
- Forum: Reaction Mechanisms, Reaction Profiles
- Topic: Mechanisms
- Replies: 3
- Views: 299
Re: Mechanisms
A reaction mechanism is the combination of all the elementary reactions that overall chemical change goes through.
- Sat Mar 14, 2020 2:07 pm
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: Activation Energy and Energy released/absorbed
- Replies: 3
- Views: 286
Re: Activation Energy and Energy released/absorbed
activation energy is always accounted for in both endo and exothermic reactions, but that doesn't determine net loss/gain of energy
- Sat Mar 14, 2020 1:40 pm
- Forum: Balancing Redox Reactions
- Topic: Bronsted Neutralization reaction
- Replies: 2
- Views: 212
Re: Bronsted Neutralization reaction
write out the skeletal reaction like H+ ---> H20. and OH- ---> H2O and then follow the regular instructions for balancing a redox reaction.
- Sat Mar 14, 2020 1:36 pm
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: Activation energy
- Replies: 7
- Views: 442
Re: Activation energy
Either Joules or Kilojoules per mole depending on the context of the problem
- Sat Mar 14, 2020 1:34 pm
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: determining a catalyst
- Replies: 5
- Views: 352
Re: determining a catalyst
If the reactant is included both in the initial reactants and the products of the final step then it is a catalyst, because it is used in the reaction but is reformed by the end
- Sat Mar 14, 2020 1:32 pm
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: Transition State Theory
- Replies: 3
- Views: 286
Re: Transition State Theory
Transition state theory deals with all reactions, while collision theory applies only to reactions in the gas phase because all other phases are colliding much more frequently.
- Sat Mar 14, 2020 1:29 pm
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: A- frequency factor
- Replies: 2
- Views: 270
Re: A- frequency factor
The frequency factor represents frequency of collisions between reactant molecules
- Fri Mar 13, 2020 3:28 pm
- Forum: Method of Initial Rates (To Determine n and k)
- Topic: Slow step
- Replies: 7
- Views: 547
Re: Slow step
If the observed rate law is given then you dont need to worry about identifying the slow step because it will just be the one that matches the given observed rate law
- Thu Mar 12, 2020 7:56 pm
- Forum: Reaction Mechanisms, Reaction Profiles
- Topic: Slow step of reaction?
- Replies: 5
- Views: 412
Re: Slow step of reaction?
You would need to run the experiment, and then check with the pre equilibrium method to confirm. In the test the slow step will most likely be given.
- Thu Mar 12, 2020 7:54 pm
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: Arrhenius equation
- Replies: 5
- Views: 366
Re: Arrhenius equation
The rate constant is proportional to the reaction rate so if rate constant doubles so does the reaction rate.
- Thu Mar 12, 2020 7:53 pm
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: Arrhenius equation
- Replies: 5
- Views: 366
Re: Arrhenius equation
You use the Arrhenius equation when you need to determine the effect of a temp change on the rate constant, which changes the overall reaction rate.
- Thu Mar 12, 2020 7:45 pm
- Forum: General Science Questions
- Topic: ENDGAME #12
- Replies: 2
- Views: 341
Re: ENDGAME #12
The pre equilibrium approach assumes that the reactants and intermediates are in equilibrium, namely the rate limiting step is at equilibrium because it is backed up at that point.
- Thu Mar 12, 2020 7:42 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Equation Sheet on Final
- Replies: 2
- Views: 298
Re: Equation Sheet on Final
Lavelles website has the link to the equations and constants sheet that we have been using, so it seems it will suffice for the content we are being tested on. The rest of the other stuff we would need like enthalpy of formation values would no question be available to us in some way.
- Thu Mar 12, 2020 7:35 pm
- Forum: General Rate Laws
- Topic: Rate-determining step
- Replies: 7
- Views: 557
Re: Rate-determining step
Usually the slow step will be given, but you might be given data about the different steps and have to analyze it to determine the rate determining step
- Thu Mar 12, 2020 7:10 pm
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: Arrhenius Equation
- Replies: 8
- Views: 543
Re: Arrhenius Equation
More specifically the Arrhenius equation can show us the impact of temperature, a catalyst, energy barrier, and frequency and orientation of collisions, which are all not shown in the rate law.
- Thu Mar 12, 2020 7:06 pm
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: Activated Complex vs Transition State
- Replies: 5
- Views: 1056
Re: Activated Complex vs Transition State
Activated complex refers to a range of configurations near the transition state that the atoms pass through in the transformation from products, while the transition state refers to only the highest potential energy configuration of the atoms during the reaction.
- Thu Mar 12, 2020 7:02 pm
- Forum: Balancing Redox Reactions
- Topic: Balancing the redox rxn in an acidic solution
- Replies: 5
- Views: 315
Re: Balancing the redox rxn in an acidic solution
The difference between balancing in an acidic or a basic solution is when you are balancing H. If you have an acidic solution you just add H+ to the side that needs H+. But with a basic solution you need to add H2O to the side that needs the H+ and OH- to the other side, so that the net difference i...
- Thu Mar 12, 2020 7:00 pm
- Forum: Balancing Redox Reactions
- Topic: Balancing the redox rxn in an acidic solution
- Replies: 5
- Views: 315
Re: Balancing the redox rxn in an acidic solution
From their oxidation numbers determine the species being oxidized and reduced and then from their unbalanced equations balance the half reactions, then have the electrons in both equations cancel by multiplying both equations to make them cancel, then you can combine the equations, cancel stuff out,...
- Thu Mar 12, 2020 6:53 pm
- Forum: General Rate Laws
- Topic: Elementary reactions
- Replies: 4
- Views: 388
Re: Elementary reactions
If the rate of the reaction is proportional to the concentration of the reactants then it is an elementary reaction
- Thu Mar 12, 2020 6:49 pm
- Forum: Kinetics vs. Thermodynamics Controlling a Reaction
- Topic: What was your favorite chem topic?
- Replies: 137
- Views: 8733
Re: What was your favorite chem topic?
Molecular shape and structure for sure Ellis! Maybe ochem will suite me better who knows
- Sun Feb 09, 2020 6:52 pm
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: First Law of Themordynamics
- Replies: 4
- Views: 234
Re: First Law of Themordynamics
The Law of Conservation of Energy was coined by Mayer in 1842, and now it has been compiled with the others as the 1st law of Thermodynamics. They are one and the same
- Sun Feb 09, 2020 6:48 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Favorability of Endothermic Reactions
- Replies: 5
- Views: 206
Re: Favorability of Endothermic Reactions
Yes because endothermic reactions require energy for the reaction to go forward, so endothermic reactions are held back by the lack of energy, but when you supply that energy in the form of heat with higher temperatures the reaction is allowed to take place more often resulting in a equilibrium shif...
- Sun Feb 09, 2020 6:46 pm
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: Delta U
- Replies: 7
- Views: 408
Re: Delta U
delta U can be 0 when a system is doing work as a reversible expansion and when the energy lost is replaced by heat flow into the system (isothermic).
- Sun Feb 09, 2020 6:42 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Enthalpy Formula
- Replies: 2
- Views: 175
Re: Enthalpy Formula
We can definitely use that equation, cause its just a reworked 1st law equation. Under constant pressure q=delta H and w= -P deltaV
- Sun Feb 09, 2020 6:33 pm
- Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
- Topic: state function mnemonic device
- Replies: 3
- Views: 1629
state function mnemonic device
Anyone know a good mnemonic device for all the state variables we need to know?
- Sun Feb 09, 2020 6:30 pm
- Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
- Topic: Clarification on a group of energy concepts
- Replies: 3
- Views: 137
Re: Clarification on a group of energy concepts
U is internal energy, meaning the energy inside of a system at a time. Is also a state function. Usually used in terms of change of internal energy, delta U
- Sun Feb 09, 2020 6:26 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Gibbs Free Energy
- Replies: 2
- Views: 128
Re: Gibbs Free Energy
Because heat and work are related to delta U directly as the two different methods showing how energy is transferred in and out of the system. Say delta U was +2kJ, the q and w could be any combination of energy values as long as the sum is +2kJ.
- Sun Feb 02, 2020 11:52 pm
- Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
- Topic: ∆U
- Replies: 8
- Views: 372
Re: ∆U
U is a state property representing internal energy of a system. So in equations it represents the change in internal energy from initial and final states.
- Sun Feb 02, 2020 11:46 pm
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: Different ways to calculate change in U
- Replies: 4
- Views: 155
Re: Different ways to calculate change in U
This is assuming it is an open or closed system with a piston, where heat and compression/expansion change, but in an isolated system the delta U is just q + w =0 because the point of an isolated system is that the internal energy doesn't change
- Sun Feb 02, 2020 11:43 pm
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: Different ways to calculate change in U
- Replies: 4
- Views: 155
Re: Different ways to calculate change in U
if delta P is 0 (under constant pressure) then delta U = delta H - P deltaV
- Sun Feb 02, 2020 11:43 pm
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: Different ways to calculate change in U
- Replies: 4
- Views: 155
Re: Different ways to calculate change in U
If delta V is 0 (constant volume) then its just deltaU = q
- Sun Feb 02, 2020 11:41 pm
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: Different ways to calculate change in U
- Replies: 4
- Views: 155
Re: Different ways to calculate change in U
In a closed system with no constants its just delta U = q +w
- Sun Feb 02, 2020 11:38 pm
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: delta U
- Replies: 9
- Views: 403
Re: delta U
if delta P is 0 (under constant pressure) then delta U = delta H - P deltaV
- Sun Feb 02, 2020 11:37 pm
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: delta U
- Replies: 9
- Views: 403
Re: delta U
If delta Volume is 0 then delta U = work
- Sun Feb 02, 2020 11:26 pm
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: Enthalpy of formation vs. heat capacity
- Replies: 2
- Views: 105
Re: Enthalpy of formation vs. heat capacity
heat capacity is the energy required to raise temp of a substance which is much different from the energy change from forming a bond. These are separate ideas as one deals with change in temp and phase of a substance and the other is chemical changes to the substance
- Sun Jan 19, 2020 11:47 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: 5% rule
- Replies: 2
- Views: 119
Re: 5% rule
Its basically there to save us time so we dont have to use the quadratic formula, plus we can assume the change to the concentration to the reactant is nonexistent which is nice as well. You can always just do the problems with the quadratic formula and it will still be correct if you ever forget th...
- Sun Jan 19, 2020 11:45 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Q
- Replies: 6
- Views: 344
Re: Q
for example, when K>Q, then the reaction shifts to the right
- Sun Jan 19, 2020 11:43 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Different ways to write K
- Replies: 3
- Views: 154
Re: Different ways to write K
Its important to differentiate between the different K subscripts because they aren't all the same, Kw is a constant while Kc Ka Kb Kp all mean different things
- Sun Jan 19, 2020 11:37 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: determining which way the reaction is going
- Replies: 5
- Views: 329
Re: determining which way the reaction is going
for example, when Kc>Q, then the reaction shifts to the right
- Sun Jan 19, 2020 11:35 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: determining which way the reaction is going
- Replies: 5
- Views: 329
Re: determining which way the reaction is going
For aqueous solutions you need to calculate the Q of the solution currently and compare it to the Kc and then you can tell which way it is going.
- Sun Jan 19, 2020 11:31 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Clarification on these statements
- Replies: 2
- Views: 165
Re: Clarification on these statements
shifted implies that the reaction was already at equilibrium and something changed it, and lies to the right/left just means that it is product/reactant favored
- Sun Jan 19, 2020 11:25 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Applying Kw
- Replies: 2
- Views: 117
Re: Applying Kw
Kw is really nifty because if you have one of [OH-] or [H30+] you can find the other because you know Kw is 10^-14. Ba(OH)2 adds to the [OH] (you know Ba2+ doesnt affect) then you use the new [OH-] to find the [H30+].
- Mon Dec 09, 2019 12:04 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Representing larger molecules
- Replies: 4
- Views: 414
Re: Representing larger molecules
Generally if your molecule has more than a few atoms its going to be listed in the order that it is formed so it generally isn't a problem, you just gotta make sure everything works out charge wise and octet rule wise. Regarding shape, you just consider one "central" atom at a time.
- Sun Dec 08, 2019 11:58 pm
- Forum: Hybridization
- Topic: Identifying Hybrid Orbitals
- Replies: 5
- Views: 445
Re: Identifying Hybrid Orbitals
Just count the # of electron densities on the atom in question and count the orbitals to hybridize from there ie s, sp, sp2, sp3
- Sun Dec 08, 2019 11:54 pm
- Forum: *Titrations & Titration Calculations
- Topic: Types of Titrations
- Replies: 2
- Views: 813
Re: Types of Titrations
The kinds we are doing right now are acid-base titrations but there are others like Redox Titrations, Precipitation Titrations. Complexometric Titrations.
- Sun Dec 08, 2019 11:52 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: AXE formula
- Replies: 7
- Views: 523
Re: AXE formula
AXE formula is used only regarding a single atom as the central atom, you can't have two As, so it simplifies it for us so all the X and Es are directly attatched to the central atom
- Sun Dec 08, 2019 10:27 pm
- Forum: Acidity & Basicity Constants and The Conjugate Seesaw
- Topic: pKa and pKb
- Replies: 2
- Views: 291
Re: pKa and pKb
literally pKa just means the -log of the concentration of the products over the concentration of the reactants
- Sun Dec 08, 2019 10:25 pm
- Forum: Calculating the pH of Salt Solutions
- Topic: pH
- Replies: 6
- Views: 344
Re: pH
p just means -log of something, so for pH that something is the concentration of H+ or H3O+ and the pOH is substituting in the concentration of OH-
- Sun Dec 08, 2019 10:22 pm
- Forum: Resonance Structures
- Topic: Bond lengths
- Replies: 2
- Views: 270
Re: Bond lengths
It's hard to put down on paper, but the electrons making the bond are being shared with other atoms so the bond is only inbetween those two atoms half the time
- Sun Dec 08, 2019 10:20 pm
- Forum: Biological Examples
- Topic: Biological Function
- Replies: 2
- Views: 276
Re: Biological Function
It kinda just squeezes itself into the H-N hydrogen bond in the backbone between two guanine or two adenine, causing a kink that prevents DNA replication
- Sun Dec 08, 2019 10:10 pm
- Forum: Biological Examples
- Topic: Heme complex & O2
- Replies: 5
- Views: 297
Re: Heme complex & O2
Yes only one O2 can bind to each coordinate structure at a time
- Sun Dec 08, 2019 10:09 pm
- Forum: Student Social/Study Group
- Topic: Cyanide
- Replies: 5
- Views: 497
Re: Cyanide
just draw a lewis dot structure of the molecule, make sure to add the extra charge somewhere, and then count the electrons directly touching the atom and find the difference between the number of electrons its supposed to have in a neutral state. Do that for both, and experiment with the bonds and t...
- Sun Dec 08, 2019 9:56 pm
- Forum: Acidity & Basicity Constants and The Conjugate Seesaw
- Topic: pka and ka
- Replies: 4
- Views: 412
Re: pka and ka
Ka is the concentration of the product over the concentration of the reactant.
- Sun Dec 08, 2019 9:47 pm
- Forum: Student Social/Study Group
- Topic: heme complex
- Replies: 5
- Views: 616
Re: heme complex
5 ligands, the oxygen it picks up acts as the 6th completing the octahedral shape
- Sun Dec 08, 2019 9:43 pm
- Forum: Bronsted Acids & Bases
- Topic: amphoteric
- Replies: 7
- Views: 1709
Re: amphoteric
if the molecule in question is able to both accept a proton and give a proton then it is amphoteric as a general rule.
- Sun Dec 08, 2019 9:40 pm
- Forum: Lewis Acids & Bases
- Topic: Lewis Acids.
- Replies: 4
- Views: 1403
Re: Lewis Acids.
Generally in an equation you can look for the more electron deficient molecule of the two assuming its a lewis acid base reaction
- Sun Dec 08, 2019 9:38 pm
- Forum: Polyprotic Acids & Bases
- Topic: Amphiprotic vs Amphoteric
- Replies: 6
- Views: 591
Re: Amphiprotic vs Amphoteric
Same thing with lewis and bronstead definitions, both mean essentially the same thing, just one is a more specific definition
- Sun Dec 01, 2019 11:57 pm
- Forum: Bronsted Acids & Bases
- Topic: Definition
- Replies: 3
- Views: 88
Re: Definition
The Bronstead-Lowry definition of acids and bases are PROTON donors/acceptors. acids being proton donors and bases being proton acceptors
- Sun Dec 01, 2019 11:50 pm
- Forum: Amphoteric Compounds
- Topic: amphoteric compounds
- Replies: 2
- Views: 188
Re: amphoteric compounds
adding on, you can test for amphoteric substances by attempting to add or remove protons from the molecule.
- Sun Dec 01, 2019 11:43 pm
- Forum: Lewis Acids & Bases
- Topic: Lewis acid & Bronstead Acid
- Replies: 3
- Views: 197
Re: Lewis acid & Bronstead Acid
A bronstead acid donates a proton (H+) while a lewis acid takes electrons
- Sun Dec 01, 2019 11:39 pm
- Forum: Naming
- Topic: Latin names
- Replies: 2
- Views: 191
Re: Latin names
No but for some compounds they are useful to know for identification purposes
- Sun Dec 01, 2019 11:38 pm
- Forum: Amphoteric Compounds
- Topic: amphiprotic and amphoteric
- Replies: 9
- Views: 701
Re: amphiprotic and amphoteric
An amphiprotic substance is one which can both donate hydrogen ions (protons) and also accept them like water. Amphoteric means that they have reactions as both acids and bases.
- Sun Nov 24, 2019 11:52 pm
- Forum: Hybridization
- Topic: Sigma and Pi bonds
- Replies: 3
- Views: 132
Re: Sigma and Pi bonds
Because they are directly overlapping with the orbitals. Pi bonds are merely parallel with the orbitals
- Sun Nov 24, 2019 11:50 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: electron and molecular geometry of H20
- Replies: 3
- Views: 232
Re: electron and molecular geometry of H20
You mean molecular shape? VSEPR is plenty good enough
- Sun Nov 24, 2019 11:48 pm
- Forum: Bond Lengths & Energies
- Topic: Boiling Point
- Replies: 4
- Views: 402
Re: Boiling Point
You always take them into account but if there is a greater intermolecular force that is stronger you consider those instead such as dipole-dipole.
- Sun Nov 24, 2019 11:43 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Seesaw shape
- Replies: 5
- Views: 243
Re: Seesaw shape
The seesaw shape occurs when you have 5e density clouds with one lone pair.
- Sun Nov 24, 2019 11:41 pm
- Forum: Electronegativity
- Topic: Hydrogen
- Replies: 6
- Views: 652
Re: Hydrogen
Hydrogen is just a weird element in general and doesn't follow a lot of the conventional rules of the periodic table.
thats why they put hydrogen all the way in the left corner even though its not an alkali metal
thats why they put hydrogen all the way in the left corner even though its not an alkali metal
- Sun Nov 24, 2019 11:39 pm
- Forum: Hybridization
- Topic: unused orbitals
- Replies: 4
- Views: 167
unused orbitals
what do you do when you only need 2 of the p orbitals to hybridize, do you just include the third one anyways or does it stay a p orbital.
- Mon Nov 18, 2019 12:00 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: VSEPR
- Replies: 2
- Views: 122
VSEPR
What does Vsepr stand for
- Sun Nov 17, 2019 11:58 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: lone pair shape
- Replies: 3
- Views: 289
lone pair shape
if when you consider what Atom to make a lone pair you consider the bond angles in reference to the other atoms why don't we take one from the axial plane say from a trigonal bipyramidal because its bond angle is 90 compared to the equitorial plane one of 120?
- Sun Nov 17, 2019 11:55 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: pentagonal bipyramidal 3 lone pairs?
- Replies: 2
- Views: 208
pentagonal bipyramidal 3 lone pairs?
starting from a pentagonal bipyramidal if you turn 3 into lone pairs where would you put the third lone pair? would it still be on the equatorial plane? or would it need to be an axial because of the lone pair repulsion?
- Thu Nov 14, 2019 12:01 am
- 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 13
- Replies: 1
- Views: 175
3F 13
does the surface area of the dipoles matter more than having multiple dipoles attached at once in terms of strength of the intermolecular forces?
- Sun Nov 10, 2019 11:50 pm
- Forum: Bond Lengths & Energies
- Topic: Double bond rotation
- Replies: 2
- Views: 182
Double bond rotation
Why do double bonds restrict rotation around an atom?
- Sun Nov 10, 2019 11:43 pm
- Forum: Coordinate Covalent Bonds
- Topic: carbon monoxide formal charges
- Replies: 5
- Views: 837
carbon monoxide formal charges
Why does carbon monoxide have a +1 charge on the oxygen and a -1 charge on the carbon?
- Sun Nov 10, 2019 11:41 pm
- Forum: Electronegativity
- Topic: oxygen vs nitrogen electronegativity
- Replies: 3
- Views: 1696
oxygen vs nitrogen electronegativity
Why is oxygen less electronegative than nitrogen?
- Sun Nov 10, 2019 11:40 pm
- Forum: Dipole Moments
- Topic: Dipole dipole forces
- Replies: 2
- Views: 252
Dipole dipole forces
What's the difference between dipole-dipole forces and induced dipole-induced dipole forces? I could not quite grasp this concept in the lecture
- Sun Nov 10, 2019 11:37 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: London Dispersion Forces
- Replies: 1
- Views: 91
London Dispersion Forces
When do London dispersion forces take priority in bonds?
- Tue Nov 05, 2019 10:57 pm
- Forum: Trends in The Periodic Table
- Topic: ionic radii
- Replies: 4
- Views: 234
ionic radii
why is it that an anion has a larger radius than its parent atom, I thought that when we add electrons the attraction gets stronger with the nucleus and it gets pulled in making it smaller.
- Tue Nov 05, 2019 8:09 pm
- Forum: Lewis Structures
- Topic: 2C5 a)
- Replies: 2
- Views: 134
2C5 a)
For drawing the lewis structure of ClO, why is it that the unpaired electron is on the chlorine instead of the oxygen, which makes the formal charges -1 and 1 instead of it being on the oxygen which would make it 0 and 0
- Sun Oct 27, 2019 6:29 pm
- Forum: Lewis Structures
- Topic: Octet Rule
- Replies: 7
- Views: 192
Re: Octet Rule
In the case of oxygen and carbon, you would say that they are sharing their electrons because it is a covalent bond. If it were a scenario where there were ionic bonds then you could say that atom A took one electron from Atom B
- Sun Oct 27, 2019 6:17 pm
- Forum: Properties of Electrons
- Topic: Electron removal
- Replies: 11
- Views: 388
Re: Electron removal
electrons that are farther away from the nucleus are easier to remove because they are less affected by the pull of the positively charged protons in the nucleus. Sort of like gravity, although idk how far that analogy can go
- Sun Oct 27, 2019 5:54 pm
- Forum: Trends in The Periodic Table
- Topic: Central Atom
- Replies: 13
- Views: 487
Re: Central Atom
The atom with lowest ionization energy because they pull other atoms toward it with its electrons that it shares
- Sun Oct 27, 2019 5:24 pm
- Forum: Formal Charge and Oxidation Numbers
- Topic: placement of the negative sign on charges
- Replies: 4
- Views: 240
placement of the negative sign on charges
is it 2- or -2 I've seen it both ways and idk if one is right and why
- Sun Oct 27, 2019 5:15 pm
- Forum: Formal Charge and Oxidation Numbers
- Topic: Formal Charge Vs. Oxidation Number
- Replies: 4
- Views: 264
Re: Formal Charge Vs. Oxidation Number
We can obtain oxidation numbers by arbitrarily assigning the electrons of each covalent bond to the more electronegative atom in the bond. This is in contrast to the Formal Charge which divides each bonding pair equally without concern for which atom may be more electronegative.
- Sun Oct 13, 2019 10:26 pm
- Forum: Properties of Light
- Topic: Explanation of Balmer and Lyman Series
- Replies: 4
- Views: 224
Re: Explanation of Balmer and Lyman Series
Balmer series lies in the visible spectrum, Lyman series lies in the UV spectrum. The graphs showed the shooting out of energy packets from electrons jumping from one energy level to another.
- Sun Oct 13, 2019 10:18 pm
- Forum: Empirical & Molecular Formulas
- Topic: Nomenclature
- Replies: 11
- Views: 2263
Re: Nomenclature
Basic ones we should be able to figure out, but in general we will be given the molecular formula in questions. Most of the words are just flavor text anyways
- Sun Oct 13, 2019 10:16 pm
- Forum: Accuracy, Precision, Mole, Other Definitions
- Topic: Unit for Avogadro's Number
- Replies: 10
- Views: 2188
Re: Unit for Avogadro's Number
Just look at what they are using in the question, cause if you understand what it represents then you can just use dimensional analysis and be done with that step, you shouldn't need to guess
- Sun Oct 13, 2019 10:12 pm
- Forum: Limiting Reactant Calculations
- Topic: Showing Work for Limiting Reactant Calculations on Tests [ENDORSED]
- Replies: 68
- Views: 6661
Re: Showing Work for Limiting Reactant Calculations on Tests [ENDORSED]
yes as long as you have the correct answer and the grader can tell what you did then you'll get credit
- Sun Oct 13, 2019 10:01 pm
- Forum: Significant Figures
- Topic: sig figs and periodic tables
- Replies: 11
- Views: 686
sig figs and periodic tables
which periodic table should I use in terms of to which decimal place cause a lot of them differ a lot.