Search found 63 matches
- Sun Mar 17, 2019 12:45 am
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: galvanic/voltaic cells
- Replies: 7
- Views: 808
Re: galvanic/voltaic cells
those terms are synonymous I believe.
- Sun Mar 17, 2019 12:44 am
- Forum: Kinetics vs. Thermodynamics Controlling a Reaction
- Topic: Rate Determining Step
- Replies: 9
- Views: 1075
Re: Rate Determining Step
The slow step can't have intermediates. You substitute them using values in the other steps.
- Sun Mar 17, 2019 12:43 am
- Forum: Balancing Redox Reactions
- Topic: balaning redox reactions
- Replies: 3
- Views: 587
Re: balaning redox reactions
yes for example, if the ion has a +2 charge and the coefficient in from of it is 2, then the charge for that species would be +4.
- Sun Mar 17, 2019 12:42 am
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: first law
- Replies: 2
- Views: 438
Re: first law
the first law also states that heat energy cannot be created or destroyed
- Sun Mar 17, 2019 12:41 am
- Forum: Ideal Gases
- Topic: ICE table
- Replies: 7
- Views: 829
Re: ICE table
You solve for Ka by setting up the equation for the equilibrium constant and pugging in the given values at equilibrium or substitute these values using X or a variation of that. Then you use algebra to solve for Ka.
- Sat Mar 16, 2019 3:29 pm
- Forum: Balancing Redox Reactions
- Topic: multiplying half reactions [ENDORSED]
- Replies: 4
- Views: 4284
multiplying half reactions [ENDORSED]
If you multiply a half reaction by a certain number in order to make the two half reactions have the same number of electrons, do you multiply the cell potential for the half reaction by that same factor?
- Fri Mar 15, 2019 11:05 pm
- Forum: Calculating Work of Expansion
- Topic: expansion work question
- Replies: 1
- Views: 505
expansion work question
If a question states that a reaction between two gasses takes place, but does not specify a volume or a change in volume, how do we know if expansion work is done?
- Fri Mar 15, 2019 7:51 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: state functions?
- Replies: 6
- Views: 728
state functions?
Ould someone explain what exactly a state function is?
- Fri Mar 15, 2019 7:50 pm
- Forum: Phase Changes & Related Calculations
- Topic: removing heat from system
- Replies: 6
- Views: 679
removing heat from system
If a reaction is exothermic, will the temperature always decrease? In not, what are the exceptions to this rule?
- Fri Mar 15, 2019 7:46 pm
- Forum: Phase Changes & Related Calculations
- Topic: removing heat from system
- Replies: 4
- Views: 666
removing heat from system
If a reaction is exothermic, will the temperature always decrease? In not, what are the exceptions to this rule?
- Fri Mar 15, 2019 6:35 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: addition of solid into a reaction
- Replies: 1
- Views: 224
addition of solid into a reaction
If the amount of a solid is added to a reaction that is already at equilibrium, will the reaction shift left or right, or will it remain at equilibrium since the item added was a solid?
- Thu Mar 14, 2019 11:12 pm
- Forum: Zero Order Reactions
- Topic: Order distinction
- Replies: 9
- Views: 1051
Re: Order distinction
the order of a reaction can be determined by looking at the rate law. Add up the exponents on each reactant and that gives you the order.
- Thu Mar 14, 2019 11:04 pm
- Forum: General Rate Laws
- Topic: slow/fast steps
- Replies: 7
- Views: 622
slow/fast steps
will it be told to us which step is the slow step and which is the fast step???? asking for a friend
- Thu Mar 14, 2019 11:01 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Cell Diagram and Ecell [ENDORSED]
- Replies: 29
- Views: 112744
Re: Cell Diagram and Ecell [ENDORSED]
jane_ni_2d wrote:how can you tell which is the anode and which is the cathode?
the anode is always on the right of the cell diagram and the cathode is on the right.
- Thu Mar 14, 2019 9:08 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Anode and Cathode
- Replies: 14
- Views: 933
Re: Anode and Cathode
In a cell diagram, the cathode was always on the right side of the double bar divider thing.
- Thu Mar 14, 2019 9:06 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Effect of concentration on cell potential
- Replies: 2
- Views: 319
Re: Effect of concentration on cell potential
simply stated, if you increase the concentration of the reactant or decrease the concentration of product the cell potential will increase.
- Thu Mar 14, 2019 9:02 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: cell diagram question
- Replies: 1
- Views: 183
cell diagram question
how do you know what is the cathode and what is the anode when looking at a cell diagram?
- Sun Feb 10, 2019 10:28 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Delta H and Delta U
- Replies: 1
- Views: 222
Delta H and Delta U
What is the difference between Delta H and Delta U?
- Mon Feb 04, 2019 4:54 pm
- Forum: Phase Changes & Related Calculations
- Topic: Heat and Condensation
- Replies: 9
- Views: 892
Re: Heat and Condensation
Condensation is exothermic, releases heat, because it is the changing of a gas state to a liquid state.
- Mon Feb 04, 2019 4:52 pm
- Forum: Phase Changes & Related Calculations
- Topic: Negative work
- Replies: 11
- Views: 1012
Re: Negative work
Yes negative work will occur when the system does work on its surroundings rather than the surroundings doing work oil the system.
- Mon Feb 04, 2019 4:50 pm
- Forum: Phase Changes & Related Calculations
- Topic: Type of systems
- Replies: 12
- Views: 1285
Re: Type of systems
An isolated and closed system are different things. A closed system allows for the exchange of energy in and out of the system. However it does not allow matter to move in and out. On the other hand, an isolated system is completely closed off and does not allow the transfer or heat or energy.
- Sun Jan 27, 2019 5:01 pm
- Forum: Phase Changes & Related Calculations
- Topic: Enthalpy signs
- Replies: 13
- Views: 1616
Re: Enthalpy signs
Delta H is positive when the reaction is endothermic and Delta H is negative when the reaction is exothermic.
- Sun Jan 27, 2019 4:57 pm
- Forum: Phase Changes & Related Calculations
- Topic: Why are phase changes endothermic?
- Replies: 11
- Views: 940
Re: Why are phase changes endothermic?
Phase changes from solid-->liquid-->vapor are endothermic reactions because it requires an input of heat and energy to break the intermolecular forces.
- Sun Jan 27, 2019 4:53 pm
- Forum: Phase Changes & Related Calculations
- Topic: Delta H
- Replies: 11
- Views: 1932
Re: Delta H
H stands for enthalpy. So delta H represents the change in enthalpy during a reaction. If delta H is positive then the reaction requires energy and is endothermic. If delta H is negative then the reaction releases energy and is exothermic.
- Wed Jan 16, 2019 5:03 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Acids
- Replies: 6
- Views: 480
Re: Acids
A weak acid or base does not dissociate fully while a strong acid or base does indeed dissociate fully ion the solution.
- Wed Jan 16, 2019 5:01 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Solids and liquids in K
- Replies: 6
- Views: 2148
Solids and liquids in K
I know that you don't include solids and liquids into the equation when calculating the equilibrium constant but could someone please explain to me why that is? Thanks friends
- Wed Jan 16, 2019 4:59 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: % Ionization
- Replies: 3
- Views: 225
Re: % Ionization
To calculate the percent ionization, divide the conjugate acid or base equilibrium molarity by the acid or base initial molarity.
- Sun Jan 13, 2019 5:43 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: True or False regarding reaction mixture [ENDORSED]
- Replies: 10
- Views: 735
Re: True or False regarding reaction mixture [ENDORSED]
yes that is basically the definition of equilibrium.
- Sun Jan 13, 2019 5:42 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: solids and liquids [ENDORSED]
- Replies: 4
- Views: 443
Re: solids and liquids [ENDORSED]
Molarity of a solid and liquid cannot change during the course of a reaction so there is no need to include them when finding K.
- Sun Jan 13, 2019 5:36 pm
- Forum: Ideal Gases
- Topic: Pv=nRT [ENDORSED]
- Replies: 12
- Views: 714
Re: Pv=nRT [ENDORSED]
Henry Dudley 1G wrote:What is the value of R?
R= 0.08206 L atm/mol K. This is given to us on tests I believe.
- Sun Dec 09, 2018 3:56 pm
- Forum: Naming
- Topic: Naming question with anion
- Replies: 2
- Views: 597
Re: Naming question with anion
anions in coordination compounds will have the endings -o -ido or -ato.
- Sun Dec 09, 2018 3:56 pm
- Forum: DeBroglie Equation
- Topic: Calculating Velocity
- Replies: 9
- Views: 1555
Re: Calculating Velocity
yes, the two equations involving velocity are p=mv and KE= 1/2mv^2
- Sun Dec 09, 2018 3:55 pm
- Forum: Hybridization
- Topic: Hybrid Orbitals
- Replies: 6
- Views: 668
Re: Hybrid Orbitals
the answer would be sp, sp2, sp3, sp3d etc
- Sun Dec 09, 2018 3:53 pm
- Forum: Biological Examples
- Topic: Cisplatin
- Replies: 3
- Views: 696
Re: Cisplatin
Cisplatin has a central atom of platinum with two Cl attached and two NH3 attached. It is tetrahedral.
- Sun Dec 09, 2018 3:52 pm
- Forum: Bond Lengths & Energies
- Topic: Shape of molecule
- Replies: 4
- Views: 738
Re: Shape of molecule
The greater the surface area off the molecule, the stronger the attraction/bond will be.
- Sun Dec 09, 2018 3:51 pm
- Forum: Polarisability of Anions, The Polarizing Power of Cations
- Topic: Size and Polarizability
- Replies: 4
- Views: 655
Re: Size and Polarizability
the size of the atom refers to the atomic radius. Atomic radius increases as you go down the periodic table and to the left on the periodic table.
- Sun Dec 09, 2018 3:49 pm
- Forum: Air Pollution & Acid Rain
- Topic: Basic Rain
- Replies: 5
- Views: 755
Re: Basic Rain
I don't think it could physically happen in the conditions present on earth but it is certainly chemically possible.
- Sun Dec 09, 2018 3:49 pm
- Forum: Acidity & Basicity Constants and The Conjugate Seesaw
- Topic: acid rain formula
- Replies: 4
- Views: 490
acid rain formula
what is the chemical equation for acid rain?? I think we went over this in class but I missed it in my notes.
- Sun Dec 09, 2018 3:47 pm
- Forum: Coordinate Covalent Bonds
- Topic: polydentates
- Replies: 5
- Views: 598
Re: polydentates
Either simply memorize the common polydentates or draw the Lewis structure to determine if has two or more bonds that attach it to the central atom.
- Sun Dec 09, 2018 10:50 am
- Forum: Electronegativity
- Topic: Trend of Electronegativity
- Replies: 18
- Views: 4088
Re: Trend of Electronegativity
Electronegativity increases as you go up the periodic table and as you go across the periodic table. Same goes for ionization energy.
- Sun Dec 09, 2018 10:50 am
- Forum: Empirical & Molecular Formulas
- Topic: Mass Percent Composition
- Replies: 7
- Views: 1087
Re: Mass Percent Composition
If it does not add up to 100%, then the question is incorrect. The elements that are apart of the compound have to add up to 100% or else there is a missing element.
- Sun Dec 09, 2018 10:47 am
- Forum: DeBroglie Equation
- Topic: Momentum
- Replies: 10
- Views: 1413
Re: Momentum
You will not always be given the momentum. Solve the debroglie equation algebraically. The question will always give you enough variables to solve for the missing ones.
- Sun Dec 09, 2018 10:45 am
- Forum: Conjugate Acids & Bases
- Topic: Conjugate Bases
- Replies: 7
- Views: 2537
Re: Conjugate Bases
Conjugate bases are the result of the acid after it donates its proton. Comjugate acids are the result of the base after it accepts its proton.
- Sun Dec 09, 2018 10:44 am
- Forum: Biological Examples
- Topic: Cisplatin
- Replies: 2
- Views: 460
Cisplatin
How does the fact that the ligands in cisplatin only bind at one site help account for the way that the drug stops cell division?
- Sat Dec 08, 2018 11:18 pm
- Forum: Quantum Numbers and The H-Atom
- Topic: Test #2 Question #5b
- Replies: 2
- Views: 358
Re: Test #2 Question #5b
nodal planes are the regions in which there is a zero % chance of finding an electron.
- Sat Dec 08, 2018 11:16 pm
- Forum: Properties of Light
- Topic: Speed of Light
- Replies: 41
- Views: 2699
Re: Speed of Light
light always travels at the same speed regardless of wavelength or amplitude. it is a constant.
- Sat Dec 08, 2018 11:15 pm
- Forum: Conjugate Acids & Bases
- Topic: Acceptor and Donor?
- Replies: 3
- Views: 552
Re: Acceptor and Donor?
yes, the acid donates the proton and its conjugate receives the proton. the same goes for bases.
- Sat Dec 08, 2018 11:14 pm
- Forum: Properties & Structures of Inorganic & Organic Acids
- Topic: HOCl vs HOI
- Replies: 9
- Views: 4114
Re: HOCl vs HOI
Cl is considerably more electronegative than I, so the O-H bond is stronger than the O-I bond. therefore it is a stronger acid.
- Sun Dec 02, 2018 11:48 pm
- Forum: Sigma & Pi Bonds
- Topic: Which bond would break first.
- Replies: 15
- Views: 2602
Re: Which bond would break first.
the pi bond would break first because it is weaker than the sigma bond. It has a lower dissociation energy so it will break first.
- Sun Dec 02, 2018 11:47 pm
- Forum: Hybridization
- Topic: tetrahedral
- Replies: 5
- Views: 497
tetrahedral
can someone explain to me why tetrahedral is sp3 hybridization?
- Sun Dec 02, 2018 11:43 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Bent vs angular?
- Replies: 15
- Views: 1126
Re: Bent vs angular?
Bent is just another name for angular. they are synonyms .
- Sun Nov 25, 2018 4:37 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Molecular Shape
- Replies: 7
- Views: 684
Re: Molecular Shape
A molecule with a seesaw molecular geometry will have a total of 5 electron domains and one of them will be a lone pair of electrons. The molecule will have angles of 120, 180, and 90 degrees at various locations.
- Sun Nov 25, 2018 4:35 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: electron arrangement and molecular geometry
- Replies: 1
- Views: 132
electron arrangement and molecular geometry
What I the difference between electron arrangement and molecular geometry? I get that molecular geometry is a more specific description of the atom but Im not sure the difference between the two terms.
- Sun Nov 25, 2018 4:32 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: pi and sigma bonds
- Replies: 9
- Views: 1383
Re: pi and sigma bonds
Sigma bonds have more energy because since they are stronger bonds, they require more energy to be broken than pi bonds. Therefore they have more energy themselves.
- Sun Nov 04, 2018 3:22 pm
- Forum: Photoelectric Effect
- Topic: intensity
- Replies: 4
- Views: 342
intensity
how does increasing the intensity of the incoming photon affect the energy of the photon. Does it increase its energy, and if so, does that increase the number of electrons that will be emitted?
- Sun Nov 04, 2018 3:19 pm
- Forum: Quantum Numbers and The H-Atom
- Topic: degeneracy in quantum numbers
- Replies: 3
- Views: 315
degeneracy in quantum numbers
Could someone explain what exactly degeneracy is in quantum numbers?
- Sun Nov 04, 2018 3:18 pm
- Forum: DeBroglie Equation
- Topic: NUETRON DIFFRACTION [ENDORSED]
- Replies: 1
- Views: 491
NUETRON DIFFRACTION [ENDORSED]
Can someone explain why neutrons do not diffract?
- Sun Oct 28, 2018 11:31 pm
- Forum: Ionic & Covalent Bonds
- Topic: Covalent Bonds
- Replies: 16
- Views: 1541
Covalent Bonds
This may be a dumb question but im a little confused. Can non metals form cations. if not, why can't they?
- Sun Oct 28, 2018 11:29 pm
- Forum: Ionic & Covalent Bonds
- Topic: Changes in Form
- Replies: 2
- Views: 345
Re: Changes in Form
No, I do not believe that the state of the molecule effects the type of bond that will form.
- Sun Oct 28, 2018 11:26 pm
- Forum: Ionic & Covalent Bonds
- Topic: the Octet rule
- Replies: 21
- Views: 4001
Re: the Octet rule
yes, there are a few exceptions. These exceptions are hydrogen, helium, lithium, beryllium. These atoms don't need to fulfill the octet rule.
- Sun Oct 07, 2018 10:28 pm
- Forum: Empirical & Molecular Formulas
- Topic: When to double moles
- Replies: 13
- Views: 986
Re: When to double moles
You can round up or down if it is within .1 of the nearest whole number.
- Sun Oct 07, 2018 10:24 pm
- Forum: Empirical & Molecular Formulas
- Topic: Converting Units
- Replies: 5
- Views: 498
Re: Converting Units
Convert the units beforehand so that the math will be valid. For example in an m1v1=m2v2 problem, the volumes must be in the same units.
- Sun Oct 07, 2018 10:11 pm
- Forum: SI Units, Unit Conversions
- Topic: What is the notation for molar mass?
- Replies: 15
- Views: 4681
Re: What is the notation for molar mass?
I am pretty sure that it is just an uppercase M (g/mol).