For 1st order reaction: ln[A] vs time is linear
For 2nd order reaction: 1/[A] vs time is linear
For 0th order reaction: [A] vs time is linear
Search found 101 matches
- Sat Mar 14, 2020 5:21 pm
- Forum: Method of Initial Rates (To Determine n and k)
- Topic: graphs and order
- Replies: 19
- Views: 852
- Sat Mar 14, 2020 5:20 pm
- Forum: First Order Reactions
- Topic: molecularity
- Replies: 3
- Views: 426
Re: molecularity
Order of a reaction is the power dependence of the rate on the concentration of the reactants. Molecularity refers to the number of reactants present (unimolecular, bimolecular, etc.)
- Fri Mar 13, 2020 2:04 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: Concentration Cells
- Replies: 8
- Views: 680
Re: Concentration Cells
Based on concentration, one side acts as the anode and the other as the cathode. Thus, one of them is reduced and the other is oxidized, depending on which has a higher concentration and produces a current.
- Fri Mar 13, 2020 2:00 pm
- Forum: Balancing Redox Reactions
- Topic: Oxidation number
- Replies: 12
- Views: 1146
Re: Oxidation number
Oxidation numbers tell you which species is being reduced or oxidized. You determine the loss of electrons when you balance the half-reactions accordingly.
- Thu Mar 12, 2020 11:20 am
- Forum: Entropy Changes Due to Changes in Volume and Temperature
- Topic: Thermodynamics problem 4.58
- Replies: 2
- Views: 232
Re: Thermodynamics problem 4.58
Yes, you can assume that. The volume and pressure return to the initial state.
- Sun Mar 08, 2020 8:10 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Platinum
- Replies: 10
- Views: 615
Re: Platinum
You add platinum as an electrode when the reactants/products are not conductive solids.
- Sun Mar 08, 2020 8:09 pm
- Forum: Balancing Redox Reactions
- Topic: Balancing basic reactions
- Replies: 8
- Views: 541
Re: Balancing basic reactions
Usually, you would add them to the side that needs oxygens. For example, reactions that involve MnO4 or Cr2O7, typically require the addition of water to the other side so that the number of oxygens are balanced. Use OH- when dealing with basic solutions. You would still add it to the side that need...
- Sun Mar 08, 2020 8:07 pm
- Forum: Reaction Mechanisms, Reaction Profiles
- Topic: 7.11
- Replies: 1
- Views: 172
Re: 7.11
The rate-determining step would have the highest activation energy, so that would have the largest hump. I am not too sure how to differentiate between the other two steps.
- Sun Mar 08, 2020 8:06 pm
- Forum: Method of Initial Rates (To Determine n and k)
- Topic: How to determine the order of a reactant
- Replies: 3
- Views: 283
Re: How to determine the order of a reactant
You can still solve it using the same method. However, you would most likely need to know the order of the other species to solve for it or would need more algebra to go through the problem.
- Sun Mar 08, 2020 8:04 pm
- Forum: General Rate Laws
- Topic: units
- Replies: 12
- Views: 579
Re: units
In your rate law equation, you'd multiply out the units of the reactants to find the units.
- Sun Mar 01, 2020 7:17 pm
- Forum: Method of Initial Rates (To Determine n and k)
- Topic: intergrated rate law
- Replies: 9
- Views: 613
Re: intergrated rate law
I believe they are given at the bottom of the equation sheet.
- Sun Mar 01, 2020 7:13 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: galvanic v. voltaic
- Replies: 1
- Views: 122
Re: galvanic v. voltaic
They are both the same thing. They turn chemical energy into electric energy.
- Sun Mar 01, 2020 7:11 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Textbook question 6M.7
- Replies: 3
- Views: 272
Re: Textbook question 6M.7
For this question, you would want to find the least reduction potential as that implies that it is better as an oxidizing agent and thus will be better at reducing other compounds. What was your method for trying to solve this problem?
- Sun Mar 01, 2020 7:05 pm
- Forum: Interesting Applications: Rechargeable Batteries (Cell Phones, Notebooks, Cars), Fuel Cells (Space Shuttle), Photovoltaic Cells (Solar Panels), Electrolysis, Rust
- Topic: Dissolved Metal
- Replies: 3
- Views: 312
Re: Dissolved Metal
If you are talking about solubility, there are lists you can find online. I don't remember the pneumonics to know this, but certain metals such as silver and mercury do not dissolve in water.
- Sun Mar 01, 2020 7:03 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: Cell Diagram
- Replies: 4
- Views: 249
Re: Cell Diagram
Yes, I believe so.
- Mon Feb 24, 2020 12:19 am
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: Test 2
- Replies: 6
- Views: 371
Re: Test 2
Because he extended it, I think he will tell us in class what to study until. It will most likely still be the end of Outline 5 and all of the electrochemistry material.
- Mon Feb 24, 2020 12:17 am
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Self Test 6L.2A
- Replies: 1
- Views: 257
Re: Self Test 6L.2A
When writing out a diagram, the || means a salt bridge and a | means an interface between phases or a porous disc. The hydrogen cell is on the left, so you'd first write the hydrogen cell portion: H2 (g) | H+ We use the bar here because both phases are interacting. Because Pt is used as the conducto...
- Mon Feb 24, 2020 12:11 am
- 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: 407
Re: Work and Battery system
A battery will always do work because it's potential must be positive for it to provide energy to do work in the first place. Energy leaves a battery when it is being used.
- Mon Feb 24, 2020 12:10 am
- 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: 358
Re: Nernst Equation usage
The Nernst equation relates the energy of a cell outside of standard conditions when the concentrations of the products and reactants change to energy in standard conditions. So, when there is a change in concentration, use the Nernst equation.
- Mon Feb 24, 2020 12:08 am
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Oxidation versus reduction
- Replies: 9
- Views: 439
Re: Oxidation versus reduction
Yes, that is the convention when representing galvanic cells.
- Sun Feb 16, 2020 11:26 pm
- Forum: Entropy Changes Due to Changes in Volume and Temperature
- Topic: ΔS for Irreversible Expansion
- Replies: 3
- Views: 268
Re: ΔS for Irreversible Expansion
For irreversible expansion, the only thing that changes is the values of Stotal and Ssurr. In irreversible expansion, the change in entropy of the system is the same as Stotal. Calculate S using the equations for changes in volume, but Stotal = Ssystem because Ssurr is 0.
- Sun Feb 16, 2020 3:12 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Free energy
- Replies: 2
- Views: 181
Re: Free energy
The pressure of a system and the ratio of products to reactants affects how much energy can be produced.
- Sun Feb 16, 2020 2:37 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: maximum work
- Replies: 5
- Views: 392
Re: maximum work
Maximum work refers to when a system is undergoing reversible expansion. that is when the maximum amount of work is done.
- Sun Feb 16, 2020 2:36 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Work and Gibbs Free Energy
- Replies: 3
- Views: 179
Re: Work and Gibbs Free Energy
I think it has to be when entropy is 0, and q = -w. So, there is no change in internal energy and no change in entropy.
- Sun Feb 16, 2020 2:35 pm
- Forum: Balancing Redox Reactions
- Topic: oxidation states (6K.1)
- Replies: 2
- Views: 74
Re: oxidation states (6K.1)
You would calculate it using the known oxidation states of elements. For example, O is typically -2, C is typically +4, etc. You can use this to calculate this by equating it to the total charge.
- Sun Feb 16, 2020 2:34 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: delta G and K
- Replies: 2
- Views: 93
- Thu Feb 06, 2020 5:48 pm
- Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
- Topic: U vs H
- Replies: 15
- Views: 1164
Re: U vs H
Delta U is the change in internal energy, whereas delta H is the change in enthalpy. I believe delta H is the total energy change, whereas delta U only accounts for the kinetic and potential energy of a system.
- Thu Feb 06, 2020 5:44 pm
- Forum: Phase Changes & Related Calculations
- Topic: equation
- Replies: 2
- Views: 90
Re: equation
No, you must add the heat of phase changes. q = mC(Tf - Ti) only calculates how much energy it takes to increase a mass of a substance by a certain amount of degrees.
- Thu Feb 06, 2020 5:43 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Explaining Le Chatelier’s principle
- Replies: 2
- Views: 214
Re: Explaining Le Chatelier’s principle
Say you have an exothermic reaction. If you increase the temperature, that means there is heat available to favor the endothermic reaction as that reaction requires heat. So, it will shift to the right side. If you decrease the temperature, that means that the heat lost needs to be replaced, and thu...
- Thu Feb 06, 2020 5:40 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Calorimeter
- Replies: 5
- Views: 372
Re: Calorimeter
A calorimeter is an apparatus that measures heat involved in a chemical reaction. To calculate the heat of reactions, you can use heat capacity and the relationships between heat absorbed and lost.
- Thu Feb 06, 2020 5:39 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Cp/Cv
- Replies: 7
- Views: 359
Re: Cp/Cv
You should assume constant pressure.
- Mon Feb 03, 2020 12:19 am
- Forum: Calculating Work of Expansion
- Topic: Reversible
- Replies: 7
- Views: 237
Re: Reversible
Equilibrium by definition means something is reversible and happens in both directions. In terms of thermodynamics, we are talking about internal and external pressure being equal.
- Mon Feb 03, 2020 12:15 am
- Forum: Concepts & Calculations Using Second Law of Thermodynamics
- Topic: Degeneracy and Entropy
- Replies: 2
- Views: 89
Re: Degeneracy and Entropy
Degeneracy refers to the possible states an object can have. So, the greater the degeneracy, the greater the entropy of the system.
- Mon Feb 03, 2020 12:12 am
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Reversible/ Irreversible Expansion
- Replies: 3
- Views: 110
Re: Reversible/ Irreversible Expansion
Reversible expansion always does more work than irreversible expansion. Additionally, the internal and external pressures are equal in reversible expansion.
- Mon Feb 03, 2020 12:11 am
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: Enthalpy and Internal Energy
- Replies: 2
- Views: 115
Re: Enthalpy and Internal Energy
Since enthalpy involves reactions, volumes are bound to change.
- Mon Feb 03, 2020 12:09 am
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Standard Reaction Enthalpy
- Replies: 4
- Views: 95
Re: Standard Reaction Enthalpy
Standard Reaction Enthalpy is the heat given off or taken up during reaction. Enthalpy of formation is difference between the standard enthalpies of products and reactants.
- Sun Jan 26, 2020 3:49 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: standard state
- Replies: 2
- Views: 62
Re: standard state
yes. Additionally, temperature and pressure should be at 25 C and 1 atm respectively.
- Sun Jan 26, 2020 3:44 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Method 3
- Replies: 2
- Views: 146
Re: Method 3
The pressure of gases are at 1 atm and the temperature is 25 C
- Sun Jan 26, 2020 3:43 pm
- Forum: Phase Changes & Related Calculations
- Topic: Enthalpy w/ Temp
- Replies: 6
- Views: 174
Re: Enthalpy w/ Temp
An increase in temperature leads to a change in enthalpy. Increasing temperature increases enthalpy, and vice versa.
- Sun Jan 26, 2020 3:41 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: heat rxn
- Replies: 2
- Views: 94
Re: heat rxn
There are 3 methods he described in class. You can add the bond enthalpies between the molecules and do broken - formed. If you have 2 reactions, you can add up the enthalpies to find the enthalpy of reaction for the combined one. Finally, you can use the enthalpy of formation to find it (products -...
- Sun Jan 26, 2020 3:38 pm
- Forum: Phase Changes & Related Calculations
- Topic: state functions
- Replies: 3
- Views: 138
Re: state functions
State functions do not care about the process to get the value. As Lavelle said in class, because this doesn't matter, you can add them up since they are specific points.
- Sun Jan 19, 2020 4:50 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Percent Protonation
- Replies: 2
- Views: 75
Re: Percent Protonation
I believe it is conjugate base/acid divided by the original compound.
- Sun Jan 19, 2020 4:49 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: Acids/Bases and Chemical Equilibrium
- Replies: 2
- Views: 114
Re: Acids/Bases and Chemical Equilibrium
A lot of it is the same. However, there will be a lot of working backwards (ex. using a Kb to find Ka for acid dissociation). Otherwise, most of the steps are essentially the same. If anything, you will have to write out the reaction yourself, requiring knowledge of common acids and bases and their ...
- Sun Jan 19, 2020 4:47 pm
- Forum: Calculating the pH of Salt Solutions
- Topic: Adding an Acid or Base in Water
- Replies: 3
- Views: 186
Re: Adding an Acid or Base in Water
It is such a small quantity of the acid that there is not enough to completely change its pH.
- Sun Jan 19, 2020 1:56 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: Homework 6E.3
- Replies: 3
- Views: 152
Re: Homework 6E.3
I believe if the Ka for the second dissociation is small enough, you can ignore the second one because little to no acid will deprotonate.
- Sun Jan 19, 2020 1:54 pm
- Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
- Topic: Strength of Acids and Bases
- Replies: 1
- Views: 151
Re: Strength of Acids and Bases
Yes, sometimes. This goes back to 14A where we looked at bond length and electronegativity (for binary acids like HI and HF and bases like LiOH and NaOH), and the number of oxygens to compare oxoacids.
- Sun Jan 12, 2020 11:12 am
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: When is the principle helpful?
- Replies: 3
- Views: 86
Re: When is the principle helpful?
Le Chatlier's principle shows us how to evaluate where equilibrium lies in a reaction. It is qualitative and helps us determine whether products or reactants are favored.
- Sun Jan 12, 2020 11:10 am
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Solids and Liquids
- Replies: 6
- Views: 120
Re: Solids and Liquids
Solids and liquids are typically in excess and thus tend to not change much in equilibrium.
- Sun Jan 12, 2020 10:57 am
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Le Chatelier's Principle
- Replies: 5
- Views: 180
Re: Le Chatelier's Principle
No, because solids and liquids are always in excess. Thus, removing or adding it would not affect equilibrium.
- Sat Jan 11, 2020 7:31 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Meaning of K [ENDORSED]
- Replies: 4
- Views: 181
Re: Meaning of K [ENDORSED]
K is the ratio of products to reactants. There are numerous ways to increase the rate of reactions, such as increasing temperatures.
- Sat Jan 11, 2020 3:25 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: 5G.1 [ENDORSED]
- Replies: 4
- Views: 170
Re: 5G.1 [ENDORSED]
I don't think higher pressure means that the equilibrium constant is larger. The constant is always set for a specific reaction regardless of pressure.
- Sat Dec 07, 2019 12:25 am
- Forum: Biological Examples
- Topic: Porphyrin
- Replies: 1
- Views: 108
Re: Porphyrin
In order for it to form a coordinate compound, it has to be bonded to a transition metal.
- Sat Dec 07, 2019 12:15 am
- Forum: Properties of Light
- Topic: speed of light and protons
- Replies: 3
- Views: 265
Re: speed of light and protons
No, the speed of protons cannot be the same as the speed of light. It is physically impossible for this to occur.
- Sat Dec 07, 2019 12:10 am
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: Orbitals
- Replies: 4
- Views: 364
Re: Orbitals
Well, in the case of the question, we can look at part a. You know that n = 2 and l = 1, meaning that it is in the p orbital. So, the orientation of the p orbitals doesn't matter and thus, there are 3 possible orbitals. For part b, there is only one that can have those three quantum numbers because ...
- Sat Dec 07, 2019 12:06 am
- Forum: Properties & Structures of Inorganic & Organic Bases
- Topic: Is trichloroacetic acid stronger than acetic acid?
- Replies: 5
- Views: 706
Re: Is trichloroacetic acid stronger than acetic acid?
Trichloroacetic acid is stronger. The Cls bonded to the molecule in place of the hydrogen has a greater electron-withdrawing power contributing to anion stability when it loses the proton.
- Sat Dec 07, 2019 12:05 am
- Forum: Bronsted Acids & Bases
- Topic: Strong vs. Weak
- Replies: 2
- Views: 241
Re: Strong vs. Weak
No. Strong acids and weak acids are determined by bond length for binary compounds and electron-withdrawing power. An exception to the trend you noticed is H2SO4, which when it dissociates, becomes HSO4-, but is still a strong acid.
- Sun Dec 01, 2019 9:31 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: NO2-
- Replies: 1
- Views: 79
Re: NO2-
Nitrogen is monodentate. The Nitrogen's lone pair is considered.
- Sun Dec 01, 2019 9:29 pm
- Forum: Lewis Acids & Bases
- Topic: Strong Acids
- Replies: 5
- Views: 297
Re: Strong Acids
The longer the bond, the stronger the acid.
- Sun Dec 01, 2019 9:28 pm
- Forum: Conjugate Acids & Bases
- Topic: the conjugate seesaw
- Replies: 5
- Views: 400
Re: the conjugate seesaw
Bases produce conjugate acids and acids produce conjugate bases. If the acid is a strong acid, its conjugate base is a weak base and vice versa.
- Sun Dec 01, 2019 9:23 pm
- Forum: Lewis Acids & Bases
- Topic: Properties of Bases
- Replies: 3
- Views: 225
Re: Properties of Bases
They react with fatty acids on the surface of your skin and produce the soapy feeling.
- Fri Nov 29, 2019 7:07 pm
- Forum: Bronsted Acids & Bases
- Topic: Definition of Bronsted and Lewis
- Replies: 1
- Views: 81
Definition of Bronsted and Lewis
Are there any examples of a compound that is a Bronsted acid/base but not a Lewis acid/base and vice versa?
- Sun Nov 24, 2019 11:48 am
- Forum: Bronsted Acids & Bases
- Topic: Acid Naming
- Replies: 2
- Views: 99
Re: Acid Naming
Yes, I think it is still cation before anion.
- Sun Nov 24, 2019 11:46 am
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Chelating Ligands
- Replies: 3
- Views: 190
Re: Chelating Ligands
Basically, a chelating ligand is one that can bond multiple times to the central metal ion by forming a ring with it. This is a result of the ability to rotate about sigma bonds so that the ligand can conform its shape to create that structure.
- Sun Nov 24, 2019 11:44 am
- Forum: Properties & Structures of Inorganic & Organic Acids
- Topic: Organic vs Inorganic Acids
- Replies: 1
- Views: 128
Re: Organic vs Inorganic Acids
In organic acids, the hydrogen is bonded to an oxygen which is bonded to a carbon. So, the electronegativity of the oxygen is decreased because it is also sharing electrons with carbon, and thus, the hydrogen is harder to remove. With inorganic acids, the hydrogen is bonded to a highly electronegati...
- Sun Nov 24, 2019 11:42 am
- Forum: Biological Examples
- Topic: Biological Examples
- Replies: 3
- Views: 175
Re: Biological Examples
I think the ones he went over in class will be good to review and know for tests, as he did go over them in-depth (cisplatin and myoglobin).
- Sun Nov 24, 2019 11:40 am
- Forum: Lewis Acids & Bases
- Topic: Acid and Base Strength
- Replies: 7
- Views: 391
Re: Acid and Base Strength
Strong acids and bases completely dissociates in water. Additionally, Ka and Kb (their respective equilibrium constants) will be really high because of this complete dissociation.
- Thu Nov 14, 2019 12:01 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: Polar Vs Nonpolar
- Replies: 7
- Views: 402
Re: Polar Vs Nonpolar
You can look at the electronegativity of the atoms and molecular shape/geometry.
- Thu Nov 14, 2019 11:59 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: H-bonds
- Replies: 4
- Views: 205
Re: H-bonds
Yes, H-bonds are a type of dipole interaction.
- Thu Nov 14, 2019 11:42 am
- Forum: Dipole Moments
- Topic: Dipole-Dipole vs. Dipole-Induced Dipole
- Replies: 1
- Views: 142
Re: Dipole-Dipole vs. Dipole-Induced Dipole
Molecules with dipole-dipole bonds have polarity on both molecules. However, with dipole-induced dipole bonds, the polarity of another molecule causes a temporary dipole to occur in another molecule. It is possible for a molecule to have both kinds of forces, it just depends on the orientation of th...
- Thu Nov 14, 2019 11:26 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: molecular shape vs. molecular geometry
- Replies: 4
- Views: 260
Re: molecular shape vs. molecular geometry
The molecular shape does not account for lone pairs of a molecule, but geometry does.
- Thu Nov 14, 2019 11:23 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: VSEPR Formula
- Replies: 3
- Views: 166
Re: VSEPR Formula
A --> Central Atom
Xn --> number of bonding electrons
En --> number of lone pairs
Xn --> number of bonding electrons
En --> number of lone pairs
- Sun Nov 10, 2019 5:36 pm
- Forum: Ionic & Covalent Bonds
- Topic: London Dispersion
- Replies: 13
- Views: 636
Re: London Dispersion
Any molecule can induce a dipole on another molecule. So, any molecule can have these dispersion forces.
- Thu Nov 07, 2019 10:12 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.5 B
- Replies: 1
- Views: 125
Re: 3F.5 B
C4H9OH forms hydrogen bonds with each other b/c of the OH group at the end of the molecule, and thus has a stronger bond between the molecules. CHI3 is more polarizable and thus has a stronger IMF.
- Thu Nov 07, 2019 10:08 am
- Forum: Photoelectric Effect
- Topic: Midterm 1
- Replies: 9
- Views: 652
Re: Midterm 1
Given the energy for exciting one electron, divide the energy absorbed by that value.
- Thu Nov 07, 2019 10:05 am
- Forum: Photoelectric Effect
- Topic: Maximum Wavelength
- Replies: 2
- Views: 252
Re: Maximum Wavelength
I don't think you can find the maximum wavelength. however, you can find the minimum wavelength by equating the energy of the light to the work function and solving for wavelength using the speed of light.
- Thu Nov 07, 2019 10:03 am
- Forum: Formal Charge and Oxidation Numbers
- Topic: Formal Charge Equation?
- Replies: 12
- Views: 497
Re: Formal Charge Equation?
Yes, that is correct. The first one treats each bond as 1 electron, the other treats it as 2.
- Sun Nov 03, 2019 8:59 pm
- Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
- Topic: Energy Level Equations
- Replies: 1
- Views: 114
Re: Energy Level Equations
Yes, you can use it to calculate energy changes across energy levels.
- Sun Nov 03, 2019 8:58 pm
- Forum: Polarisability of Anions, The Polarizing Power of Cations
- Topic: Polarity vs Polarizability
- Replies: 3
- Views: 226
Re: Polarity vs Polarizability
Polarity is how charged an atom is. Polarizability is how likely it is to induce a dipole with another molecule. So the more polar a bond is, the more likely it is to polarize another molecule.
- Sat Nov 02, 2019 2:50 pm
- Forum: Electronegativity
- Topic: Figuring it out without the trend?
- Replies: 4
- Views: 125
Re: Figuring it out without the trend?
You can look at the rows they are in to determine which one is more electronegative.
- Sat Nov 02, 2019 2:49 pm
- Forum: Trends in The Periodic Table
- Topic: Ionization Energy from the Review
- Replies: 4
- Views: 136
Re: Ionization Energy from the Review
The half-filled p orbital is more stable than the p orbital of oxygen. It is easier for an oxygen atom to lose/gain an electron to fill up the remaining unpaired shells as it is in a more unstable form.
- Sat Nov 02, 2019 2:46 pm
- Forum: Trends in The Periodic Table
- Topic: Exceptions
- Replies: 3
- Views: 100
Re: Exceptions
One exception is for the ionization energy of group 15 and 16 elements. Although it typically increases across a row, the ionization energy of group 16 elements is actually less than group 15 elements because the half-filled orbital is more stable, and harder to remove an electron.
- Fri Oct 25, 2019 1:26 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: 1D. 11 prob
- Replies: 3
- Views: 93
Re: 1D. 11 prob
l corresponds to one of the s, p, d, or f subshells. So, based on that, you can determine the number of orbital.
- Fri Oct 25, 2019 11:41 am
- Forum: Resonance Structures
- Topic: Delocalization
- Replies: 3
- Views: 102
Re: Delocalization
It means that the electrons in bonds are not set. For example, with benzene, the double bonds in the ring are not set. There are other configurations of it, and so you shouldn't see it as one set bond arrangement.
- Fri Oct 25, 2019 11:32 am
- Forum: Administrative Questions and Class Announcements
- Topic: Week 5 Homework
- Replies: 9
- Views: 392
Re: Week 5 Homework
Do problems from chemical bonds.
- Fri Oct 25, 2019 11:32 am
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Number of Valence Electrons
- Replies: 5
- Views: 325
Re: Number of Valence Electrons
The number of valence electrons is 7 for manganese. It includes the 3d orbital electrons because the difference in energy between the 3d orbital and 4s is very small, so they essentially are in the same energy level. However, transition metals can have multiple valence states, so technically 2 or 7 ...
- Fri Oct 25, 2019 11:03 am
- Forum: Photoelectric Effect
- Topic: HW Question 1.31
- Replies: 1
- Views: 178
Re: HW Question 1.31
If I understand this scenario correctly, I would assume that the beam of light is ejecting an electron from the lithium and it is detected by the sensor. This essentially is the photoelectric effect, as you have light pointing at a metal that is causing an electron to be ejected. You are dealing wit...
- Wed Oct 16, 2019 3:15 pm
- Forum: Quantum Numbers and The H-Atom
- Topic: X Y and Z
- Replies: 7
- Views: 234
Re: X Y and Z
It depends on which energy level the electron is in as well as the convention the problem uses when listing l values. The plane will correspond to the appropriate electron plane. I recommend watching the corresponding module for this lecture as he shows an example where he does just this.
- Wed Oct 16, 2019 2:46 pm
- Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
- Topic: Problem from Audio Visual Focus Topic
- Replies: 1
- Views: 91
Re: Problem from Audio Visual Focus Topic
You would solve this using the delta E equation. Substitute hv (Planck's constant * frequency) for delta E and set up the other side using the difference in energy (-hR/n^2-(-hR)/n^2). Plug in the appropriate numbers and solve. Don't forget to inverse and square root properly and you should get the ...
- Wed Oct 16, 2019 2:42 pm
- Forum: SI Units, Unit Conversions
- Topic: Fundamentals Problem Question
- Replies: 2
- Views: 232
Re: Fundamentals Problem Question
For this problem, you need two separate equations to answer both parts. For part a, the net ionic equation represents only the ions that participate in the reaction to form the precipitate. So, you would have one with copper and hydroxide on the reactant side, and on the other, the precipitate by it...
- Wed Oct 16, 2019 11:55 am
- Forum: Properties of Light
- Topic: 1B #9
- Replies: 5
- Views: 143
Re: 1B #9
Calculate the frequency first using the wavelength of the light. Then, use that frequency to calculate the energy of an individual photon. Divide 32 by that value and multiply by 2 to get the number of photons emitted in 2 seconds. For the second part, divide by Avogadro's number to get number of mo...
- Wed Oct 16, 2019 11:52 am
- Forum: Properties of Light
- Topic: 1B #19
- Replies: 2
- Views: 141
Re: 1B #19
Use the De Broglie wavelength equation to solve for the wavelengths of both. Then, divide the wavelength of the neutron by the proton's so that you get the percentage.
- Wed Oct 09, 2019 6:47 pm
- Forum: SI Units, Unit Conversions
- Topic: Fundamentals L35
- Replies: 5
- Views: 250
Re: Fundamentals L35
T is metric tons and it is 1,000 kilograms or 1,000,000 grams.
- Wed Oct 09, 2019 6:44 pm
- Forum: Balancing Chemical Reactions
- Topic: H.7 Catalysts [ENDORSED]
- Replies: 4
- Views: 431
Re: H.7 Catalysts [ENDORSED]
Catalysts typically lower the activation energy of a reaction so that it can happen faster. I assume that the catalyst does the same in that reaction.
- Wed Oct 09, 2019 6:40 pm
- Forum: Photoelectric Effect
- Topic: Energy of Photon = Work Function
- Replies: 4
- Views: 475
Energy of Photon = Work Function
What happens when the energy of the photon is equal to the work function? How is the electron emitted if there is no excess energy to be converted into kinetic energy?
- Wed Oct 09, 2019 6:30 pm
- Forum: Significant Figures
- Topic: Range of Sig Figs
- Replies: 8
- Views: 483
Re: Range of Sig Figs
2.9995 would be correct because you round to the appropriate number of sig figs.
- Wed Oct 09, 2019 2:32 pm
- Forum: Student Social/Study Group
- Topic: Atomic Spectra: Energy Levels
- Replies: 3
- Views: 144
Re: Atomic Spectra: Energy Levels
Yes, the calculations would be for that. There might also be problems where they have you solve for the energies of a quantum level given the change in energy and the final or initial energy or solve for wavelengths, frequencies, etc. You can also look at the homework problems for the corresponding ...
- Thu Oct 03, 2019 12:23 am
- Forum: Molarity, Solutions, Dilutions
- Topic: Fundamental G.13
- Replies: 4
- Views: 234
Re: Fundamental G.13
First, you must solve for the new concentration after the florist dilutes it with 3 more liters of water. Using this molarity, you can calculate the number of moles each plant receives in the 100 mL. Now, for every mole of fertilizer, there are 2 moles of nitrogen. So, using this ratio, you can solv...
- Thu Oct 03, 2019 12:18 am
- Forum: Molarity, Solutions, Dilutions
- Topic: M1V1=M2V2 [ENDORSED]
- Replies: 3
- Views: 695
Re: M1V1=M2V2 [ENDORSED]
This equation demonstrates that initial and final moles are always equal when diluting a solution. So, yes, when you do multiply it out, the units for volume cancel out, but you are left with the number of moles. This equation helps us calculate volume needed for dilutions or new concentrations usin...
- Tue Oct 01, 2019 8:58 pm
- Forum: Molarity, Solutions, Dilutions
- Topic: Question M9
- Replies: 1
- Views: 121
Re: Question M9
Net ionic equations only show the reactants that participate in the reaction. Since the reaction produces a copper hydroxide, the only reactants that matter are the copper and hydroxide. The sodium dissociates in the solution and does not contribute to the precipitate.
- Tue Oct 01, 2019 8:50 pm
- Forum: Balancing Chemical Reactions
- Topic: Question H7a
- Replies: 6
- Views: 293
Re: Question H7a
Hydroxide has a -1 charge. Group 2 elements (including calcium), always have a +2 charge. So, for the charges to balance you would need 2 hydroxide molecules for the calcium ion. This applies to Group 1 elements where they always have a +1 charge. Elements in group 13, 14, 15, 16, and 17 have a +3, ...