Search found 99 matches
- Fri Mar 13, 2020 5:30 pm
- Forum: General Rate Laws
- Topic: Factors Affecting k
- Replies: 83
- Views: 4534
Re: Factors Affecting k
it changes with temperature.
- Fri Mar 13, 2020 5:30 pm
- Forum: Zero Order Reactions
- Topic: Calculus
- Replies: 10
- Views: 689
Re: Calculus
Probably just to derive/integrate the formulas.
- Fri Mar 13, 2020 5:29 pm
- Forum: First Order Reactions
- Topic: Determining Order
- Replies: 7
- Views: 442
Re: Determining Order
You can look at units of rate constant for the orders of each reactant and add them together.
- Fri Mar 13, 2020 5:29 pm
- Forum: First Order Reactions
- Topic: Half Life
- Replies: 8
- Views: 503
Re: Half Life
You can see the difference when you derive the half life formula from each rate law.
- Fri Mar 13, 2020 5:28 pm
- Forum: First Order Reactions
- Topic: Half Life
- Replies: 13
- Views: 798
Re: Half Life
Half lives are used more for real world applications.
- Tue Mar 10, 2020 11:38 pm
- Forum: Kinetics vs. Thermodynamics Controlling a Reaction
- Topic: Molecularity
- Replies: 12
- Views: 759
Re: Molecularity
molecularity is the number of species that participate.
- Tue Mar 10, 2020 11:37 pm
- Forum: Kinetics vs. Thermodynamics Controlling a Reaction
- Topic: thermo or kinetics?
- Replies: 9
- Views: 714
Re: thermo or kinetics?
thermo is used to determine how a reaction progressed while thermo is used to look at initial and final states.
- Tue Mar 10, 2020 11:36 pm
- Forum: General Rate Laws
- Topic: orders
- Replies: 6
- Views: 440
Re: orders
first determine orders of individual reactants and then add them together for the overall order.
- Tue Mar 10, 2020 11:35 pm
- Forum: Kinetics vs. Thermodynamics Controlling a Reaction
- Topic: Activation Energy
- Replies: 17
- Views: 854
Re: Activation Energy
activation energy is not the same as change in enthalpy.
- Tue Mar 10, 2020 11:34 pm
- Forum: Kinetics vs. Thermodynamics Controlling a Reaction
- Topic: kinetics
- Replies: 9
- Views: 610
Re: kinetics
it is trapped if it has high activation energy, even though it may be thermodynamically favorable.
- Sat Feb 29, 2020 5:05 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: Concentration Cells
- Replies: 6
- Views: 503
Re: Concentration Cells
A concentration cell has different concentrations.
- Sat Feb 29, 2020 5:04 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: Concentration Cells and Nernst Equation
- Replies: 4
- Views: 314
Re: Concentration Cells and Nernst Equation
It is for concentration cells and when the concentrations are not at the standard ones.
- Sat Feb 29, 2020 5:03 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Pt in cell diagrams
- Replies: 3
- Views: 226
Re: Pt in cell diagrams
If there's no solid, Pt is used.
- Sat Feb 29, 2020 5:03 pm
- Forum: Balancing Redox Reactions
- Topic: Oxidation Numbers
- Replies: 7
- Views: 636
Re: Oxidation Numbers
There are certain elements where we know their oxidation but for a molecule, the oxidation numbers of the atoms should add up to the total charge.
- Thu Feb 27, 2020 4:17 pm
- Forum: Kinetics vs. Thermodynamics Controlling a Reaction
- Topic: Activation Energy
- Replies: 16
- Views: 1416
Re: Activation Energy
Activation energy is the energy needed to a reaction to occur.
- Thu Feb 20, 2020 10:34 pm
- Forum: Balancing Redox Reactions
- Topic: oxidation numbers
- Replies: 8
- Views: 548
Re: oxidation numbers
You use the known oxidation numbers for some elements and fill in the rest. The sum of all the oxidation numbers should add up to the total charge of the molecule.
- Thu Feb 20, 2020 10:34 pm
- Forum: Balancing Redox Reactions
- Topic: Balancing Redox Reactions
- Replies: 5
- Views: 296
Re: Balancing Redox Reactions
I don't think it matters where the molecules are placed as long as they are balanced correctly and on the correct side.
- Thu Feb 20, 2020 10:33 pm
- Forum: Balancing Redox Reactions
- Topic: oxidation numbers
- Replies: 4
- Views: 279
Re: oxidation numbers
A decrease in number means a decrease in charge, which signifies reduction because it gains an electron and goes down in charge. vice versa for increase
- Thu Feb 20, 2020 10:32 pm
- Forum: Balancing Redox Reactions
- Topic: Oxidation Numbers
- Replies: 5
- Views: 302
Re: Oxidation Numbers
There's some rules to follow, such as oxygen is almost always 2-, fluorine is almost always 1-, etc. The oxidation numbers of all the elements should add up to the charge.
- Thu Feb 20, 2020 10:30 pm
- Forum: Balancing Redox Reactions
- Topic: Oxidation numbers
- Replies: 6
- Views: 412
Re: Oxidation numbers
H2 is an exception because it is a diatomic and in its most stable form.
- Tue Feb 11, 2020 3:02 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Units for delta H
- Replies: 3
- Views: 295
Re: Units for delta H
delta H is in kj/mol. if it was just kj, it would be q or just energy.
- Tue Feb 11, 2020 3:01 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: delta U = q + w
- Replies: 6
- Views: 378
Re: delta U = q + w
it depends on the system.
- Tue Feb 11, 2020 3:00 pm
- Forum: Calculating Work of Expansion
- Topic: Constant Volume and Pressure Values
- Replies: 8
- Views: 300
Re: Constant Volume and Pressure Values
I think we just need to know the monoatomic ones.
- Tue Feb 11, 2020 2:59 pm
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: adiabatic
- Replies: 19
- Views: 982
Re: adiabatic
adiabatic means where there is no transfer of heat, so q is zero.
- Tue Feb 11, 2020 2:59 pm
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: Internal energy of ideal gas
- Replies: 6
- Views: 488
Re: Internal energy of ideal gas
only delta U, or change in internal energy is 0.
- Tue Feb 11, 2020 2:58 pm
- Forum: Calculating Work of Expansion
- Topic: calculating work of a reversible reaction
- Replies: 5
- Views: 363
Re: calculating work of a reversible reaction
If the system is doing work, or expanding, work would be negative. If it had work being done on it, or being compressed, it would be positive.
- Tue Feb 11, 2020 2:57 pm
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: Thermodynamics
- Replies: 6
- Views: 291
Re: Thermodynamics
both would be negative since the system is losing energy.
- Tue Jan 28, 2020 4:57 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: reaction enthalpy
- Replies: 14
- Views: 446
Re: reaction enthalpy
Energy is released when bonds form, therefore making it exothermic and the enthalpy would be negative since the final molecule has less energy than the separate atoms.
- Tue Jan 28, 2020 4:56 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Best Method of the 3 Given?
- Replies: 7
- Views: 218
Re: Best Method of the 3 Given?
I think method one is the most accurate since the enthalpies are given as exact for each reaction.
- Tue Jan 28, 2020 4:55 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Hess's Law
- Replies: 11
- Views: 332
Re: Hess's Law
You add enthalpies together, reverse signs for reverse reactions, and multiply if you multiply the whole reaction.
- Tue Jan 28, 2020 4:54 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Bond Enthalpies
- Replies: 11
- Views: 248
Re: Bond Enthalpies
The bond enthalpies are averages of all the possible ones, so it is less accurate.
- Tue Jan 28, 2020 4:53 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Adding Enthalpies
- Replies: 5
- Views: 186
Re: Adding Enthalpies
You add the enthalpies and reverse signs when the reaction is reversed.
- Thu Jan 23, 2020 4:21 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: Endothermic Reaction.
- Replies: 7
- Views: 231
Re: Endothermic Reaction.
If delta H is positive, it means the reaction is endothermic .
- Thu Jan 23, 2020 4:18 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: Endothermic Reaction.
- Replies: 7
- Views: 231
Re: Endothermic Reaction.
If delta H is positive, it means the reaction is endothermic .
- Thu Jan 23, 2020 4:17 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: pKa to Kb
- Replies: 12
- Views: 552
Re: pKa to Kb
pKa + pKb is pKw, which is 14.
- Thu Jan 23, 2020 4:16 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: exothermic reactions
- Replies: 19
- Views: 1893
Re: exothermic reactions
In an exothermic reaction, the heat is written as a product. Increasing a product would push the reaction to the left and favor the reactants.
- Thu Jan 23, 2020 4:15 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Le Chatelier's Principle
- Replies: 19
- Views: 1609
Re: Le Chatelier's Principle
You use the principle when the reaction is no longer at equilibrium.
- Thu Jan 23, 2020 4:14 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Changes in pressure
- Replies: 5
- Views: 109
Re: Changes in pressure
Adding inert gases will not change concentration of anything and will just be present among both sides of the molecules. The inert gas does not react with anything.
- Sat Jan 18, 2020 5:52 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: Reaction shifts right or left?
- Replies: 14
- Views: 1490
Re: Reaction shifts right or left?
A left shift favors reactants and a right shift favors products.
- Sat Jan 18, 2020 5:49 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: Partial Pressure
- Replies: 19
- Views: 687
Re: Partial Pressure
Usually, it will be given.
- Sat Jan 18, 2020 5:47 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: Q < K
- Replies: 16
- Views: 794
Re: Q < K
When Q is less than K, more products tend to form.
- Sat Jan 18, 2020 5:46 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Eq. constants & solubility
- Replies: 3
- Views: 162
Re: Eq. constants & solubility
The greater the ksp, the greater the solubility.
- Sat Jan 18, 2020 5:43 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Kc sig figs
- Replies: 4
- Views: 157
Re: Kc sig figs
Take the least amount of sig figs.
- Tue Jan 07, 2020 4:30 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Writing expression for K
- Replies: 5
- Views: 195
Re: Writing expression for K
Px is used for gases to represent their partial pressure. In other cases, you would use concentration.
- Tue Jan 07, 2020 4:29 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Equilibrium and Equilibrium Constant
- Replies: 4
- Views: 118
Re: Equilibrium and Equilibrium Constant
Changing the equilibrium means you take the reaction out of the equilibrium by removing or adding reactant/product. Changing the constant would mean you have to change pressure and temperature.
- Tue Jan 07, 2020 4:27 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Very Large K
- Replies: 12
- Views: 2523
Re: Very Large K
A large K would mean the product concentration in the equation is much greater than the reactant. Therefore, the reaction at equilibrium favors the products.
- Tue Jan 07, 2020 4:26 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Equilibrium Constant for Solids/Gases
- Replies: 5
- Views: 191
Re: Equilibrium Constant for Solids/Gases
Solids and liquids are not included in the equation.
- Tue Jan 07, 2020 4:25 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Kc versus K
- Replies: 4
- Views: 248
Re: Kc versus K
K can be represented with both Kp and Kc.
- Fri Dec 06, 2019 1:12 pm
- Forum: Sigma & Pi Bonds
- Topic: sigma and pi bonds
- Replies: 27
- Views: 1599
Re: sigma and pi bonds
Yes, sigma bonds are single bonds. Pi bonds are any bonds on top of the first one.
- Fri Dec 06, 2019 1:07 pm
- Forum: Ionic & Covalent Bonds
- Topic: intermolecular vs intramolecular
- Replies: 17
- Views: 1867
Re: intermolecular vs intramolecular
Intermolecular is between molecules while intramolecular is within a molecule.
- Mon Dec 02, 2019 10:02 pm
- Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
- Topic: increasing pH and decreasing pH
- Replies: 4
- Views: 300
Re: increasing pH and decreasing pH
Yes the higher the hydronium ion concentration, the lower the pH and the more acidic.
- Mon Dec 02, 2019 10:01 pm
- Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
- Topic: Hydronium concentration = 1.5M, negative ph?
- Replies: 3
- Views: 244
Re: Hydronium concentration = 1.5M, negative ph?
I think we can assume it is zero since the pH scale is between 0 and 14.
- Mon Dec 02, 2019 5:16 pm
- Forum: Conjugate Acids & Bases
- Topic: Product of Acid and Base
- Replies: 5
- Views: 333
Re: Product of Acid and Base
The proton combines with the hydroxide ion to make water and the two other ions made a salt.
- Mon Dec 02, 2019 4:46 pm
- Forum: Conjugate Acids & Bases
- Topic: How many gets transferred?
- Replies: 1
- Views: 139
Re: How many gets transferred?
One proton gets transferred at a time.
- Mon Dec 02, 2019 4:45 pm
- Forum: Conjugate Acids & Bases
- Topic: Identifying conjugate acids & bases
- Replies: 3
- Views: 197
Re: Identifying conjugate acids & bases
Water acts as the base. It can do this because it is an amphoteric molecule. I also think you meant the hydronium ion instead of the hydroxide ion.
- Tue Nov 26, 2019 6:23 pm
- Forum: Lewis Acids & Bases
- Topic: Lewis and Bronsted
- Replies: 5
- Views: 346
Re: Lewis and Bronsted
The lewis definition involves the transfer of a pair of electrons. The bronsted definition involves transfer of a proton.
- Tue Nov 26, 2019 6:22 pm
- Forum: Properties & Structures of Inorganic & Organic Acids
- Topic: Use of Bronsted or Lewis Definitions
- Replies: 7
- Views: 330
Re: Use of Bronsted or Lewis Definitions
Both are ok.
- Tue Nov 26, 2019 6:21 pm
- Forum: Amphoteric Compounds
- Topic: How can compounds be amphoteric?
- Replies: 5
- Views: 244
Re: How can compounds be amphoteric?
Amphoteric compounds can both donate and accept a proton.
- Tue Nov 26, 2019 6:20 pm
- Forum: Bronsted Acids & Bases
- Topic: Definition
- Replies: 5
- Views: 158
Re: Definition
A bronsted acid is one that can give up a proton. A lewis acid is one that can accept a pair of electrons.
- Tue Nov 26, 2019 6:20 pm
- Forum: Bronsted Acids & Bases
- Topic: Difference
- Replies: 3
- Views: 192
Re: Difference
Bronsted acids involving the donating and accepting of a proton while lewis acids involve donating and accepting of a pair of electrons.
- Thu Nov 21, 2019 3:26 pm
- Forum: Biological Examples
- Topic: Ligands
- Replies: 7
- Views: 857
Re: Ligands
There is usually one d metal atom.
- Thu Nov 21, 2019 3:15 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: cisplatin
- Replies: 4
- Views: 173
Re: cisplatin
Cisplatin can bind to DNA molecules and prevent cells from dividing. It is used as a treatment for cancer.
- Thu Nov 21, 2019 3:04 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Coordinate bonds
- Replies: 3
- Views: 203
Re: Coordinate bonds
Coordinate covalent bonds form when the ligand donates both electrons in the electron pair.
- Thu Nov 21, 2019 11:03 am
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Coordination Covalent Bonds
- Replies: 4
- Views: 173
Re: Coordination Covalent Bonds
In a coordinate covalent bond, the nonmetal has a lone pair and donates both electrons to the bond.
- Thu Nov 21, 2019 11:03 am
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Coordination Number
- Replies: 2
- Views: 144
Re: Coordination Number
It's the number of bonds on the central atom.
- Thu Nov 21, 2019 11:02 am
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Ligands
- Replies: 4
- Views: 209
Re: Ligands
Ligands are not the central atom. They bond to the central atom.
- Thu Nov 14, 2019 7:48 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Electrons
- Replies: 9
- Views: 433
Re: Electrons
Electrons naturally repel each other so having a greater distance between them would lower these repulsion forces.
- Thu Nov 14, 2019 7:47 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: VESPR Model of H2O
- Replies: 12
- Views: 791
Re: VESPR Model of H2O
H2O is bent because of the two lone pairs on the oxygen.
- Thu Nov 14, 2019 7:46 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Trigonal Pyramid vs Trigonal Planar
- Replies: 6
- Views: 438
Re: Trigonal Pyramid vs Trigonal Planar
Trigonal planar is in one plane and has three areas of e density while trigonal pyramidal is 3d and has 4 areas.
- Thu Nov 14, 2019 7:45 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Molecular Shape Name
- Replies: 17
- Views: 817
Re: Molecular Shape Name
I think we will need to know most of the names.
- Thu Nov 14, 2019 6:38 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Drawing Molecular Structures
- Replies: 8
- Views: 494
Re: Drawing Molecular Structures
The solid triangle represents the atom coming out of the page towards you. The dashed lines represent the atom going away from you into the page. Lines are used to draw atoms that are on the same plane as the paper. The other two symbols are when the atoms come out of the plane.
- Fri Nov 08, 2019 12:57 am
- Forum: Octet Exceptions
- Topic: General principles of octet exception
- Replies: 7
- Views: 312
Re: General principles of octet exception
Atoms with n=3 and greater can accommodate more than 8 electrons in its valence shell.
- Fri Nov 08, 2019 12:56 am
- Forum: Octet Exceptions
- Topic: Lewis Acids and Bases?
- Replies: 11
- Views: 493
Re: Lewis Acids and Bases?
A lewis base would donate a pair of electrons and a lewis acid would accept a pair of electrons.
- Fri Nov 08, 2019 12:55 am
- Forum: Octet Exceptions
- Topic: elements in 3p block
- Replies: 8
- Views: 490
Re: elements in 3p block
They are able to use their 3d orbital. They are just normally not filled.
- Fri Nov 08, 2019 12:54 am
- Forum: Lewis Structures
- Topic: Lewis Structure
- Replies: 4
- Views: 311
Re: Lewis Structure
The most stable would be the one in which the most atoms have the lowest formal charges.
- Tue Nov 05, 2019 10:34 am
- Forum: Coordinate Covalent Bonds
- Topic: Single, double, and triple bonds
- Replies: 6
- Views: 214
Re: Single, double, and triple bonds
It depends on the atom radii. If the atoms are larger, the bond is weaker because the pull of the nucleus weaker due to how far apart they are from the electrons.
- Sat Nov 02, 2019 5:30 pm
- Forum: Bond Lengths & Energies
- Topic: Single bond vs double bond
- Replies: 14
- Views: 821
Re: Single bond vs double bond
The numbers are the bond length between the carbon atoms.
- Sat Nov 02, 2019 5:27 pm
- Forum: Octet Exceptions
- Topic: Octet Exceptions
- Replies: 3
- Views: 220
Re: Octet Exceptions
The element needs to have a d orbital, so only those from n=3 and greater.
- Sat Nov 02, 2019 5:22 pm
- Forum: Coordinate Covalent Bonds
- Topic: Electronegativity
- Replies: 12
- Views: 1682
Re: Electronegativity
As you go down a period, there is more and more shielding, making the nuclear charge weaker. Therefore, it is harder to pull an electron in, decreasing the electronegativity.
- Sat Nov 02, 2019 5:19 pm
- Forum: Lewis Structures
- Topic: central atom
- Replies: 16
- Views: 2127
Re: central atom
Use the element with the lowest electronegativity.
- Sat Nov 02, 2019 5:02 pm
- Forum: Sigma & Pi Bonds
- Topic: Double bond
- Replies: 15
- Views: 509
Re: Double bond
Double bonds are used to satisfy the octet rule, which lowers the energy of the molecule, making it more stable.
- Sat Nov 02, 2019 5:00 pm
- Forum: Resonance Structures
- Topic: Resonance structure
- Replies: 4
- Views: 184
Re: Resonance structure
NH4 does not have resonance but some molecules that do are the nitrate and carbonate ions.
- Mon Oct 28, 2019 10:56 am
- Forum: Ionic & Covalent Bonds
- Topic: Ionic Bonds confusion
- Replies: 7
- Views: 258
Re: Ionic Bonds confusion
It is with a metal and nonmetal since a metal tends to give electrons away to the nonmetal.
- Mon Oct 28, 2019 10:56 am
- Forum: Ionic & Covalent Bonds
- Topic: Covalent Bonds
- Replies: 14
- Views: 954
Re: Covalent Bonds
Covalent bonds are just between two nonmetals.
- Mon Oct 28, 2019 10:55 am
- Forum: Ionic & Covalent Bonds
- Topic: Ground State
- Replies: 11
- Views: 485
Re: Ground State
The ground state is when the atom is at the lowest possible energy. It corresponds to the electron configuration.
- Sun Oct 20, 2019 11:17 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Hund's Rule
- Replies: 5
- Views: 255
Re: Hund's Rule
There are electron repulsions with paired electrons, therefore it is not favorable to have paired electrons before parallel ones.
- Sun Oct 20, 2019 11:16 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Excited State
- Replies: 3
- Views: 180
Re: Excited State
If an electron isn't following one of the rules, it is in an excited state. Atoms fill their orbitals with electrons starting from the lowest energy levels and with parallel spin. If an electron skips one of these levels, it is in an excited state.
- Sun Oct 20, 2019 11:14 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Multi-electron atoms
- Replies: 7
- Views: 278
Re: Multi-electron atoms
Some ions have only one electron, such as He 1+ or Li 2+.
- Wed Oct 16, 2019 11:44 pm
- Forum: Quantum Numbers and The H-Atom
- Topic: Quantum Numbers question, ml
- Replies: 2
- Views: 120
Re: Quantum Numbers question, ml
ml can only range from -l to +l. So for example, if l=2, ml can be -2, -1, 0, 1, or 2. Therefore if l=0, ml can only be 0.
- Thu Oct 10, 2019 3:59 pm
- Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
- Topic: Photon Absorption/Emission
- Replies: 8
- Views: 389
Re: Photon Absorption/Emission
The photon will be emitted again once the electron falls back down from the excited level. The photon has to have the exact amount of energy needed in order for the electron to absorb it and move to a higher energy level.
- Thu Oct 10, 2019 3:39 pm
- Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
- Topic: Decreasing gap between energy level
- Replies: 6
- Views: 1386
Re: Decreasing gap between energy level
As the electrons get farther from the nucleus, the pull of the nucleus becomes weaker. Therefore, it takes less energy to remove that electron from that level.
- Thu Oct 10, 2019 3:11 pm
- Forum: Einstein Equation
- Topic: E=hv [ENDORSED]
- Replies: 52
- Views: 18043
Re: E=hv [ENDORSED]
It represents the energy of a photon, but can be used to find energy needed.
- Thu Oct 10, 2019 10:32 am
- Forum: Properties of Light
- Topic: Light intensity
- Replies: 6
- Views: 178
Re: Light intensity
The higher intensity in terms of wave properties would just mean a larger amplitude.
- Thu Oct 10, 2019 12:05 am
- Forum: Properties of Light
- Topic: Speed of Light constant
- Replies: 7
- Views: 290
Re: Speed of Light constant
I usually just use 3.00 unless theres like another value with a crazy amount of sig figs. It should be fine since Prof. Lavelle also used it.
- Tue Oct 01, 2019 4:37 pm
- Forum: Significant Figures
- Topic: Sig Figs for Tests/Quizzes
- Replies: 7
- Views: 423
Re: Sig Figs for Tests/Quizzes
Points probably won't be taken off for the correct number of sigfigs. I save all my decimals till the very end and then round where I need to so I'm not off by a few decimals.
- Tue Oct 01, 2019 4:34 pm
- Forum: Accuracy, Precision, Mole, Other Definitions
- Topic: Balancing Equations [ENDORSED]
- Replies: 25
- Views: 1961
Re: Balancing Equations [ENDORSED]
You would probably lose points. Also even though the equation is balanced without whole numbers, it doesn't make sense for there to be half of a molecule. It would not only make more sense but also make solving problems later on easier with whole number coefficients.
- Tue Oct 01, 2019 4:32 pm
- Forum: Molarity, Solutions, Dilutions
- Topic: Dilution
- Replies: 9
- Views: 514
Re: Dilution
The amount of solute doesn't change, only the solvent. So when you are calculating dilutions, you only need to account for the added solvent since you already know the amount of solute already.
- Tue Oct 01, 2019 11:56 am
- Forum: Accuracy, Precision, Mole, Other Definitions
- Topic: What does dilution mean in a chemistry problem?
- Replies: 8
- Views: 822
Re: What does dilution mean in a chemistry problem?
Dilution is when you add more solvent, decreasing the concentration of the overall solution since the amount of solute remains the same.
- Tue Oct 01, 2019 10:33 am
- Forum: Accuracy, Precision, Mole, Other Definitions
- Topic: Avogadro's Number
- Replies: 4
- Views: 263
Re: Avogadro's Number
I used 6.022 x 10^23 in all the problems and I've gotten the right answer so I would say use that, especially if Dr. Lavelle uses it too.