Search found 102 matches
- Sat Mar 14, 2020 7:31 pm
- Forum: Ideal Gases
- Topic: 5% Rule
- Replies: 6
- Views: 552
Re: 5% Rule
Its for simplifying ICE calculations. If the end result is less than 5%, than the approximation is accurate.
- Sat Mar 14, 2020 10:44 am
- Forum: Experimental Details
- Topic: Collision Theory
- Replies: 8
- Views: 1159
Re: Collision Theory
Collision theory connects temperature and energy. Molecules need to have enough kinetic energy that, upon collision, there is enough energy to overcome the energy barrier. By increasing temperature, the molecules have a higher kinetic energy and therefore are more likely to overcome the energy barri...
- Sat Mar 14, 2020 10:42 am
- Forum: Second Order Reactions
- Topic: determining order
- Replies: 9
- Views: 568
Re: determining order
You can use experimental data by plotting the data using the formulas observed in class and try to achieve a linear plot. If they give you a list of intermediate steps, the slow step will be the rate law which will give indication to the order.
- Sat Mar 14, 2020 10:39 am
- Forum: Reaction Mechanisms, Reaction Profiles
- Topic: reaction mechanisms
- Replies: 2
- Views: 206
Re: reaction mechanisms
Either can be used and the steady state is more versatile. But, for Lavelle, we will only be using the pre-equilibrium.
- Sat Mar 14, 2020 10:38 am
- Forum: Reaction Mechanisms, Reaction Profiles
- Topic: Slow step
- Replies: 3
- Views: 259
Re: Slow step
The slow step should have a rate law that is equivalent to the observed rate law.
- Sat Mar 14, 2020 10:36 am
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: Activation Energy
- Replies: 3
- Views: 353
Re: Activation Energy
Does this mean that free energy of activation measured without the enzyme? Or is it needed in relation to the activation energy with the enzyme?
- Sat Mar 14, 2020 10:33 am
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: Catalysts
- Replies: 8
- Views: 461
Re: Catalysts
Homogeneous are in the same phase and move around the designated volume like it was a reactant or product. When it is a heterogeneous, it is a different phase and the reactants rest on the surface and are adsorbed.
- Sat Mar 14, 2020 10:31 am
- Forum: Second Order Reactions
- Topic: Finding out order
- Replies: 22
- Views: 902
Re: Finding out order
Units correlate to the reaction order to ensure the final units work out. Hence, the units for the rate constant will indicate the rate order.
- Sat Mar 14, 2020 10:29 am
- Forum: Method of Initial Rates (To Determine n and k)
- Topic: rate constant
- Replies: 5
- Views: 408
Re: rate constant
kr is the reaction rate constant which relates the rate of the initial concentrations to the rate of the chemical reaction.
- Sat Mar 14, 2020 10:26 am
- Forum: First Order Reactions
- Topic: Half Life
- Replies: 13
- Views: 785
Re: Half Life
Julia Holsinger_1A wrote:How do you determine the order of the reaction when needing to calculate half life? Will it always be given?
To determine the order, you will likely use scientific data, are told, or can assume pseudo-first reaction if the information permits.
- Sat Mar 14, 2020 10:25 am
- Forum: First Order Reactions
- Topic: Half Life
- Replies: 13
- Views: 785
Re: Half Life
Half lives can be used to determine how much product is left after any amount of time. if you know the half life, you set the equation: (1/2)^x =1/A where a is the value of how much of the original product remains. For example, 1/9 of the initial amount. Solve for x to see how many half lives there ...
- Sat Mar 14, 2020 10:21 am
- Forum: Environment, Ozone, CFCs
- Topic: Homogeneous Catalysts and Ozone
- Replies: 6
- Views: 1593
Re: Homogeneous Catalysts and Ozone
•OH + CO → •HOCO
•HOCO + O2 → HO2• + CO2
HO2• + NO → •OH + NO2
NO2 + hν → NO + O• , λ<400 nm
O• + O2 → O3
If there is no sunlight available to break NO2, the production of ozone will stop.
•HOCO + O2 → HO2• + CO2
HO2• + NO → •OH + NO2
NO2 + hν → NO + O• , λ<400 nm
O• + O2 → O3
If there is no sunlight available to break NO2, the production of ozone will stop.
- Sat Mar 14, 2020 10:16 am
- Forum: Environment, Ozone, CFCs
- Topic: stoichiometric coefficients
- Replies: 19
- Views: 1380
Re: stoichiometric coefficients
This shows the standard reaction where you want to get exactly one mole of product, which means we use fractions for the reactants if needed.
- Sat Mar 14, 2020 10:14 am
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: Concentration Cells
- Replies: 2
- Views: 263
Concentration Cells
How do you know which side is oxidized and reduced in concentration cells?
- Sat Mar 14, 2020 10:11 am
- Forum: Balancing Redox Reactions
- Topic: Half Reactions
- Replies: 15
- Views: 756
Re: Half Reactions
It depends on the solution. If it is acidic, you add H+ to balance H. If it is basic, you add h2o to the side that needs H and OH- to the other side.
- Sat Mar 14, 2020 10:09 am
- Forum: Balancing Redox Reactions
- Topic: Oxidation number
- Replies: 12
- Views: 1097
Re: Oxidation number
Oxidation number related to the charge of the element within its molecule. You compare its charge on each side of the equation. If it becomes more positive, it loses electrons and is therefore oxidized. If it becomes more negative (less positive), it gains electrons and is therefore reduced.
- Sat Mar 14, 2020 10:07 am
- Forum: Balancing Redox Reactions
- Topic: OH vs H
- Replies: 12
- Views: 845
Re: OH vs H
In basic solutions, H+ is not readily available. To balance H, you add h20 to one side and then oh- to the other. This is essentially adding an H+ in a different manner.
- Fri Mar 13, 2020 6:56 pm
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: Catalysts and Rates
- Replies: 10
- Views: 640
Re: Catalysts and Rates
They do effect the rate of the reactions but to not effect the equilibrium constants.
- Fri Mar 13, 2020 6:55 pm
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: Homework 7E3
- Replies: 2
- Views: 188
Re: Homework 7E3
That is a sound way to do it. It is about convenience and ease, also considering which mathematical approach you understand the best.
- Fri Mar 13, 2020 6:54 pm
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: Elementary Steps
- Replies: 4
- Views: 343
Re: Elementary Steps
It is about probability. The probability that a specific set of four molecules not only collide at the exact same time, but with enough energy to break and form new bonds. Through a probability lens, these occurrences are unlikely.
- Fri Mar 13, 2020 6:53 pm
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: Catalysis
- Replies: 11
- Views: 792
Re: Catalysis
Catalysis increases the forward and reverse reaction rates by lowering activation energy.
- Fri Mar 13, 2020 6:52 pm
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: Activated Complex vs Transition State
- Replies: 5
- Views: 965
Re: Activated Complex vs Transition State
An activated complex can be a varying number of configurations between two molecules. In the activated complex, the complex can either form products or disassociate to form the original reactants. The transition state is the one of highest potential energy and when this energy level is reached, the ...
- Fri Mar 13, 2020 6:49 pm
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: Arrhenius Equation
- Replies: 8
- Views: 511
Re: Arrhenius Equation
Arrhenius behavior is when the graph of 1/kr is linear when plotted against 1/T
- Fri Mar 13, 2020 6:47 pm
- Forum: Reaction Mechanisms, Reaction Profiles
- Topic: Slow Step Mechanism
- Replies: 7
- Views: 463
Re: Slow Step Mechanism
It depends on the reaction but from what we have been given thus far, it seems as though lavelle will tell us which is the fast and slow step.
- Fri Mar 13, 2020 6:46 pm
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: Equilibrium Constant
- Replies: 2
- Views: 155
Equilibrium Constant
Is the equilibrium constant the same in the presence of a catalyst because the forward and reverse reaction rate increase the same so the ratio stays the same?
- Fri Mar 13, 2020 2:05 pm
- Forum: Reaction Mechanisms, Reaction Profiles
- Topic: Molecularity
- Replies: 1
- Views: 121
Molecularity
What is the use of molecularity? As in, can I get an example where knowing the molecularity of elementary reactions are helpful?
- Fri Mar 13, 2020 1:53 pm
- Forum: First Order Reactions
- Topic: Pseudo-First Order Reaction
- Replies: 4
- Views: 338
Re: Pseudo-First Order Reaction
You can use pseudo first order when trying to find out how the reaction is dependent on only one reactant. This is done by assuming the other concentrations are very large and do not change, so only our molecule of concern is studied.
- Fri Mar 13, 2020 1:52 pm
- Forum: Reaction Mechanisms, Reaction Profiles
- Topic: Identifying First and Second Order
- Replies: 3
- Views: 194
Identifying First and Second Order
How do reaction mechanisms indicate first or second order? Can i get a description on things to look for to identify and connect the two?
- Fri Mar 13, 2020 1:51 pm
- Forum: Second Order Reactions
- Topic: second order relation to second order integrated law
- Replies: 5
- Views: 443
Re: second order relation to second order integrated law
There is also a helpful page in the book for this which shows how the equation is derived. It is page 606.
- Fri Mar 13, 2020 1:44 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: 663
Concentration Cells
Can someone explain to me how a concentration cell works if it is using the same molecule? As in, where do the electrons come from and go if only one molecule is there for redox reactions
- Tue Mar 10, 2020 12:27 am
- Forum: General Rate Laws
- Topic: Book Problem 7A.17
- Replies: 3
- Views: 290
Book Problem 7A.17
You are given a table with the initial concentrations and the intial rates for the reaction A+B+C= Products How do you tell if a reaction is zero order with respect to a reactant? Is it if the other two concentrations are the same and only the reactant of interest concentration changes and it still ...
- Wed Feb 19, 2020 10:36 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Max Potential
- Replies: 5
- Views: 302
Re: Max Potential
Max potential occurs right before the cells are connected because the electric potential is the greatest (nothing is flowing between them.) As time goes on, the system heads towards equilibrium and the electric potential decreases.
- Wed Feb 19, 2020 10:25 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Anode and Cathode position
- Replies: 5
- Views: 311
Re: Anode and Cathode position
I would always double check what is being oxidized and what is being reduced to ensure it is correct.
- Wed Feb 19, 2020 10:24 pm
- Forum: Balancing Redox Reactions
- Topic: Reduction vs. oxidation
- Replies: 29
- Views: 1071
Re: Reduction vs. oxidation
A good saying is LEO says GER: Losing Electron Oxidizing, Gaining Electrons Reduction
Looking at the change in the oxidation numbers helps indicate if it is a reduction or oxidation.
Looking at the change in the oxidation numbers helps indicate if it is a reduction or oxidation.
- Wed Feb 19, 2020 10:22 pm
- Forum: Balancing Redox Reactions
- Topic: Understanding Half-Reactions
- Replies: 11
- Views: 631
Re: Understanding Half-Reactions
half reactions let you balance how the oxidation and reduction is occurring, bringing in the right number of water, hydrogen, and hydroxide molecules to bring about a balanced redox reaction.
- Wed Feb 19, 2020 10:19 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Dead Battery
- Replies: 6
- Views: 376
Re: Dead Battery
The system will reach equilibrium where the charges will no longer flow. In terms of a galvanic cell, adding a salt bridge can keep the system "neutral" and allow charges to keep flowing rather than build up.
- Wed Feb 19, 2020 10:16 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: galvanic cell structure
- Replies: 8
- Views: 354
Re: galvanic cell structure
While looking at the charges of the cathode and the anode, the cathode has a more positive charge while an anode has a more negative charge. Hence, cathode attract electrons which is associated with reduction and the anode is the opposite, which is associated with oxidation.
- Sun Feb 16, 2020 8:51 pm
- Forum: Calculating Standard Reaction Entropies (e.g. , Using Standard Molar Entropies)
- Topic: reaction entropy
- Replies: 7
- Views: 566
Re: reaction entropy
It will be the products minus the reactants to find the net change. This applies to other state functions as well.
- Sun Feb 16, 2020 8:49 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: How to interpret reversible/irreversible graphs
- Replies: 6
- Views: 645
Re: How to interpret reversible/irreversible graphs
For a reversible reaction, it occurs under constant temperature because it is such a slow and small change that it remains balanced between the internal and external environment.
- Sun Feb 16, 2020 8:45 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Why are exothermic reactions generally spontaneous?
- Replies: 16
- Views: 1027
Re: Why are exothermic reactions generally spontaneous?
If delta H is negative, then to determine if the reaction is spontaneous, you have to look at T*delta S. In order to make G positive given a negative delta H, entropy would have to be negative and overpower the delta H. This is unlikely because the release of energy from an exothermic reaction is un...
- Sun Feb 16, 2020 8:42 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Equilibrium [ENDORSED]
- Replies: 3
- Views: 266
Re: Equilibrium [ENDORSED]
Because there is no net change occurring, no total work is done. That is because the energy is in equilibrium as well.
- Sun Feb 16, 2020 8:41 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Spontaneous
- Replies: 13
- Views: 733
Re: Spontaneous
If gibbs free energy is less than zero, it is spontaneous. There is a chart in the book to correlate the two parts of gibbs free, the enthalpy and entropy part of the equation.
- Sun Feb 16, 2020 8:39 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Midterm Curve
- Replies: 45
- Views: 2058
Re: Midterm Curve
Tests themselves are not curved but the grade distribution is based on everyone FINAL grade.
- Tue Feb 04, 2020 6:03 pm
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: closed vs isolated
- Replies: 14
- Views: 402
Re: closed vs isolated
Closed allows only energy transfer while isolated does not allow the transfer of energy nor matter.
- Tue Feb 04, 2020 6:01 pm
- Forum: Environment, Fossil Fuels, Alternative Fuels
- Topic: Why energy crisis?
- Replies: 8
- Views: 4355
Re: Why energy crisis?
The energy of the universe is constant, so yes the amount of energy is always the same. However, the form the energy is in is why there is a crises. We combust the fossil fuels and the energy is released, but not back into the form of fossil fuels. Hence, a crises.
- Tue Feb 04, 2020 5:59 pm
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: extensive property
- Replies: 12
- Views: 585
Re: extensive property
Extensive properties are directly related to the amount of material present. The amount of heat required to rais X amount of a substance one degree is extensive. Density is NOT an extensive property. Whether you have a whole gallon of water or a drop of water, density is the same.
- Tue Feb 04, 2020 5:56 pm
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: Work done BY vs work done ON
- Replies: 9
- Views: 242
Re: Work done BY vs work done ON
Work is energy times distance. The way I think of it is: who is losing energy in order to receive the desired change? If the system is compressed, energy must be going into the system and work must be done ON the system in order for this to occur. For the system to expand, it loses energy to the sur...
- Tue Feb 04, 2020 5:52 pm
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: Phase change
- Replies: 20
- Views: 734
Re: Phase change
Delta H is positive as the system absorbs energy in order to go to a liquid phase AND the energy remains there to keep it in a liquid phase.
- Tue Feb 04, 2020 5:51 pm
- Forum: Calculating Work of Expansion
- Topic: temperature
- Replies: 7
- Views: 346
Re: temperature
To get to Kelvin, you add 273 to the degrees Celsius. This is a linear relationship so one degree Celsius will be one degree kelvin.
- Tue Feb 04, 2020 5:47 pm
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: q and w
- Replies: 10
- Views: 531
Re: q and w
For work, it is relative to what your are referencing. In terms of this class, the focus is our system. If the system does work, work is positive (the system loses energy). If work is done on the system, it is negative (energy added to the system).
- Tue Feb 04, 2020 5:44 pm
- Forum: Calculating Work of Expansion
- Topic: second equation
- Replies: 8
- Views: 209
Re: second equation
It is really used for when the pressure isn't constant do to find the work done, it is the integral of the subsequent volume changes. It is also used to derive the first formula.
- Sat Feb 01, 2020 6:49 pm
- Forum: Phase Changes & Related Calculations
- Topic: Open vs Isolated System
- Replies: 15
- Views: 1235
Re: Open vs Isolated System
I ask myself: can energy leave or enter? Can matter leave or enter?
By answering these, you can find if it is open (yes/yes), closed (no/yes), or isolated (no/no).
By answering these, you can find if it is open (yes/yes), closed (no/yes), or isolated (no/no).
- Sat Feb 01, 2020 6:48 pm
- Forum: Phase Changes & Related Calculations
- Topic: 4A. 1 Identifying open and closed system
- Replies: 11
- Views: 2568
Re: 4A. 1 Identifying open and closed system
For the bomb calorimeter, their design is made to be an isolated system. This is just a fact listed in the book and the only way you can distinguish it between a closed or isolated system.
- Sat Feb 01, 2020 6:47 pm
- Forum: Phase Changes & Related Calculations
- Topic: 4A. 1 Identifying open and closed system
- Replies: 11
- Views: 2568
Re: 4A. 1 Identifying open and closed system
For D, matter and energy can be exchanged into the engine. Therefore, it is an open system.
- Sat Feb 01, 2020 6:45 pm
- Forum: Phase Changes & Related Calculations
- Topic: Calculating Work
- Replies: 12
- Views: 6434
Re: Calculating Work
Use w=-P∆V
-w=work
-P= pressure
-∆V= change in volume
you are given P and the change in volume can be calculated using the given diameters and some geometric formulas.
-w=work
-P= pressure
-∆V= change in volume
you are given P and the change in volume can be calculated using the given diameters and some geometric formulas.
- Sat Feb 01, 2020 6:43 pm
- Forum: Phase Changes & Related Calculations
- Topic: DELTA H Vs Q
- Replies: 7
- Views: 357
Re: DELTA H Vs Q
Delta H is a measure of enthalpy whereas Q is the energy in transit. Delta H is a state of the system.
- Sat Feb 01, 2020 6:40 pm
- Forum: Phase Changes & Related Calculations
- Topic: Reversible and Irreversible
- Replies: 5
- Views: 224
Re: Reversible and Irreversible
I have a similar question as above, is anyone able to answer? I would assume it is irreversible since the energy is then lost to heat and cannot be recovered?
- Sat Feb 01, 2020 6:38 pm
- Forum: Phase Changes & Related Calculations
- Topic: Phase Changes
- Replies: 17
- Views: 642
Re: Phase Changes
Temperature does not change during a phase change. However, there is still energy being put into the system. The energy is going into breaking intermolecular bonds rather than thermal heat.
- Thu Jan 23, 2020 6:36 pm
- Forum: Phase Changes & Related Calculations
- Topic: Autoprotolysis
- Replies: 15
- Views: 723
Re: Autoprotolysis
Autoprotolysis is proton transfer between the same type of molecule. In this class, water was the example. 2H20 <-> h3o+ + oh-
- Thu Jan 23, 2020 6:30 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Exothermic vs. Endothermic reactions
- Replies: 12
- Views: 893
Re: Exothermic vs. Endothermic reactions
From our current tools given, he will give the change in enthalpy and from that information you will have to determine if it is exo/endo, and he may ask questions that utilize Le Chateliers principle in regards to temp.
- Thu Jan 23, 2020 6:26 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Prep for Test 1
- Replies: 16
- Views: 576
Re: Prep for Test 1
You need to know how to calculate and convert between the two, but memorizing values is unnecessary.
- Thu Jan 23, 2020 6:25 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Temperature
- Replies: 6
- Views: 187
Re: Temperature
Temperature can be thought of as a reactant. If adding heat to a reaction, it will favor whichever direction has the positive change in H. This is because forming more of the "energy rich" molecule will harness more of the heat to minimize the net change of temperature of the environment. ...
- Thu Jan 23, 2020 6:14 pm
- Forum: Phase Changes & Related Calculations
- Topic: Enthalpy Units
- Replies: 3
- Views: 159
Re: Enthalpy Units
It is the variations of energy units. The SI unit is Joules. However, calories/kilocalories are also common and you can convert between Joules and calories.
- Thu Jan 16, 2020 10:31 am
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Quadratic
- Replies: 6
- Views: 153
Re: Quadratic
I would recommend becoming familiar with it in general though. It will help you timewise to know how to use the formula and not waste time on the math when you can be focusing more on the chemistry at hand.
- Thu Jan 16, 2020 10:25 am
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: When to use K and Kp
- Replies: 12
- Views: 355
Re: When to use K and Kp
Typically it will specify. When given all gases, you will likely use partial pressure. If they specify concentration when given gasses, you may need to use PV=nRT to convert between the two. K is a general symbol which can apply to Kp or Kc. In this class he has had us specify which we are using.
- Thu Jan 16, 2020 10:24 am
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: Reaction shifts right or left?
- Replies: 14
- Views: 1427
Re: Reaction shifts right or left?
Yes, this is correct. It is about looking at the concentrations in the Q value to see if the reaction will shift right or left.
- Thu Jan 16, 2020 10:23 am
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Endothermic/Exothermic Rxns and Delta H
- Replies: 3
- Views: 495
Re: Endothermic/Exothermic Rxns and Delta H
The equation is extremely simplified and ignores all of the moments in which, yes, forming bonds did release energy. However, when thinking about it with common sense, it is an endothermic reaction. First, light (energy) is required for photosynthesis to happen. Secondly, our bodies use glucose as a...
- Thu Jan 16, 2020 10:17 am
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: Reaction Quotient
- Replies: 11
- Views: 250
Re: Reaction Quotient
They are measured the same. The key difference is K is ONLY at equilibrium where as Q is at any point in the reaction. Q can tell us which way the reaction will favor when compared to Q.
- Sat Jan 11, 2020 3:22 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: ICE Table Ratios
- Replies: 7
- Views: 212
Re: ICE Table Ratios
You would get the same answer but it is easier when using whole numbers to calculate--plus, it will then match your balanced equation.
- Sat Jan 11, 2020 3:18 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Why does only Temp affect K?
- Replies: 10
- Views: 16396
Re: Why does only Temp affect K?
Temperature can alter the stability of the molecules in the reaction. Hence, by changing the temperature, the products or reactants may become more/less stable at different temperatures. With this information, the reaction my shift to the left or right, altering our K.
- Sat Jan 11, 2020 3:14 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: K vs. Q
- Replies: 10
- Views: 497
Re: K vs. Q
K is an equilibrium constant that is most favorable to the reaction under certain conditions. Q measures where the reaction is at any given time in relationship to K.
- Sat Jan 11, 2020 3:12 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Change in k
- Replies: 11
- Views: 469
Re: Change in k
K tells us the ratio of concentrations between products and reactants that is most favorable given the current conditions. So, with changing concentrations, you will be changing your Q. Then, the reaction will work to bring Q towards K. The total amount of product and reactant will change, but their...
- Sat Jan 11, 2020 3:09 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Significant Figures
- Replies: 8
- Views: 356
Re: Significant Figures
It could be either. Sig figs are based off of the smallest number of sig figs initially measured.
- Fri Dec 07, 2018 1:15 pm
- Forum: Polyprotic Acids & Bases
- Topic: oxacids and carboxylic acids
- Replies: 5
- Views: 1141
Re: oxacids and carboxylic acids
Carboxylic acids are common of organic chemistry whereas oxacids will appear in general chemistry (with metals)
- Fri Dec 07, 2018 1:10 pm
- Forum: Lewis Acids & Bases
- Topic: How to Identify Lewis acid and Bases
- Replies: 4
- Views: 1367
Re: How to Identify Lewis acid and Bases
Also helpful is to remember Lewis Acids will accept lone pairs and Lewis Bases with donate lone pairs, hence your conclusion was correct
- Fri Dec 07, 2018 1:08 pm
- Forum: Conjugate Acids & Bases
- Topic: Neutralization Reactions
- Replies: 6
- Views: 920
Re: Neutralization Reactions
Always remember water is a product, so there will be a cation paired with a hydroxyl and an anion paired with a H+ ion. So work backwards to fill in the missing pieces
- Thu Nov 29, 2018 1:23 pm
- Forum: Naming
- Topic: Naming Coordination Compounds
- Replies: 9
- Views: 1022
Re: Naming Coordination Compounds
I believe we will need to be able to remember them; he stated during lecture that we can find the common ligands in the textbook, which makes it seem like we should be familiar with them.
- Thu Nov 29, 2018 1:21 pm
- Forum: Biological Examples
- Topic: cisplatin in stopping DNA replication
- Replies: 3
- Views: 321
Re: cisplatin in stopping DNA replication
An important key to remember is the CIS part of the molecule (as a TRANS version does exist). This allows both ligands to bind to the DNA and effectively start replication whereas the TRANS version is unable to do this.
- Sat Nov 24, 2018 4:50 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Lone pairs determining shape?
- Replies: 5
- Views: 1608
Re: Lone pairs determining shape?
There are two versions of a molecule that we use to identify shape. The molecular shape does NOT use lone pair electrons when determining shape; however, they play an influence in bond angles that can therefore slightly alter the molecular shape. The electronic geometry of a molecule does consider l...
- Sat Nov 24, 2018 4:46 pm
- Forum: Hybridization
- Topic: Steps to figure out hybridization
- Replies: 3
- Views: 463
Re: Steps to figure out hybridization
When you draw the lewis structure, you will be able to identify how many bonding regions there are. Then, you just need to make sure the hybridization state has the same number of orbitals as bonding regions.
- Thu Nov 15, 2018 12:00 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: Boiling point
- Replies: 12
- Views: 2070
Re: Boiling point
A rod shaped molecule has stronger intermolecular forces, meaning they have a stronger attraction to each other. To break this stronger connection requires more energy, resulting in a higher boiling point. The opposite is true for the spherical shape.
- Thu Nov 15, 2018 11:56 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Molecular shape
- Replies: 3
- Views: 348
Re: Molecular shape
A good thing to think about are organic molecules (hydrocarbons, more specifically, alkanes). Van Der Waals forces are a strong contributor to the boiling point of molecules. Longer, more linear alkanes have a stronger Van Der Waals forces and therefore it requires more energy to break this attracti...
- Thu Nov 15, 2018 11:46 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Thanksgiving [ENDORSED]
- Replies: 14
- Views: 1463
Re: Thanksgiving [ENDORSED]
I would make plans for either option and he should tell us in the upcoming classes if it will be canceled
- Thu Nov 08, 2018 2:09 pm
- Forum: Bond Lengths & Energies
- Topic: bond lengths and strengths
- Replies: 9
- Views: 885
Re: bond lengths and strengths
In a less scientific way, it is easier to break a thin stick that is about 6 feet long (a single bond) rather than a stick that is 3 centimeters long (a triple bond). Hence, single bonds are weaker than double or triple because they are longer.
Note, the chosen lengths are arbitrary.
Note, the chosen lengths are arbitrary.
- Thu Nov 08, 2018 2:06 pm
- Forum: Ionic & Covalent Bonds
- Topic: Periodic Trends
- Replies: 3
- Views: 369
Re: Periodic Trends
When it comes to diagonal elements, it is generally difficult to [censored] their comparing electronegativity because you experience two opposing forces that influence electronegativity. In the case of sodium and calcium, sodium appears to have a higher electronegativity because it is in the period ...
- Thu Nov 08, 2018 1:57 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: Difference between the bonds
- Replies: 4
- Views: 593
Difference between the bonds
Can someone explain the difference between dipole-dipole versus dipole-induced dipole?
- Thu Nov 01, 2018 9:58 pm
- Forum: Formal Charge and Oxidation Numbers
- Topic: Formal charge purpose
- Replies: 40
- Views: 6842
Re: Formal charge purpose
Calculating formal charges allows us to draw the most stable structure. For example, it will tell us if we should consider double bonds within the molecules to create more stability.
- Thu Nov 01, 2018 9:48 pm
- Forum: Resonance Structures
- Topic: Electron movements
- Replies: 2
- Views: 287
Electron movements
How do the electrons move within atoms to create the "blended" characteristic?
- Thu Nov 01, 2018 9:46 pm
- Forum: Coordinate Covalent Bonds
- Topic: Tetrafluoroborate anion
- Replies: 3
- Views: 969
Re: Tetrafluoroborate anion
Going off of this question, why does the boron trifluoride atom not form a coordinate covalent bond with the fluorine to get an octet opposed to adding an additional fluorine atom?
- Thu Oct 25, 2018 11:40 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Electron Configuration Exceptions [ENDORSED]
- Replies: 3
- Views: 479
Electron Configuration Exceptions [ENDORSED]
Why do elements such as copper not follow our expected electron configurations
- Thu Oct 25, 2018 11:38 pm
- Forum: Einstein Equation
- Topic: Units
- Replies: 6
- Views: 887
Units
Are remembering units for this equation, and others, necessary? Or are they given on the test?
- Thu Oct 25, 2018 11:36 pm
- Forum: Quantum Numbers and The H-Atom
- Topic: Vocabulary confusion
- Replies: 2
- Views: 553
Vocabulary confusion
What is the difference between principal quantum number and magnetic quantum number?
- Thu Oct 25, 2018 11:36 pm
- Forum: Quantum Numbers and The H-Atom
- Topic: Vocabulary confusion
- Replies: 2
- Views: 395
Vocabulary confusion
What is the difference between principal quantum number and magnetic quantum number?
- Thu Oct 18, 2018 7:59 pm
- Forum: Heisenberg Indeterminacy (Uncertainty) Equation
- Topic: Representation
- Replies: 4
- Views: 566
Representation
What does the numerical value given by the uncertainty principle actually mean?
- Thu Oct 18, 2018 7:55 pm
- Forum: *Shrodinger Equation
- Topic: Shrodinger equation
- Replies: 2
- Views: 326
Shrodinger equation
What is the relationship between energy and the shrodinger equation? I do not understand the "operate a change on" part of the notes.
- Thu Oct 18, 2018 7:45 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: Nodal Planes
- Replies: 1
- Views: 291
Nodal Planes
Can someone explain the concept of nodal planes and their relationship to orbital shapes.
- Thu Oct 11, 2018 4:20 pm
- Forum: Photoelectric Effect
- Topic: Photoelectric Effect
- Replies: 4
- Views: 246
Re: Photoelectric Effect
The scientists expected that increasing the intensity of the light would eject electrons from a metals surface (which did not happen). The scientists then had to change their thought process. Instead of increasing the intensity, they increased the frequency, which ejected electrons. This data reflec...
- Thu Oct 11, 2018 4:08 pm
- Forum: Photoelectric Effect
- Topic: Electrons
- Replies: 2
- Views: 161
Electrons
How do we detect the electrons whose velocity is zero when the threshold energy and energy of the photon are equal?
- Thu Oct 11, 2018 4:03 pm
- Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
- Topic: Atomic Spectra
- Replies: 1
- Views: 96
Atomic Spectra
Question: Why does hydrogen emits multiple wavelengths to create its own "fingerprint", yet it only has one electron whose energy level could change can emit the frequencies?
- Sun Oct 07, 2018 6:29 pm
- Forum: Molarity, Solutions, Dilutions
- Topic: Molarity Formula [ENDORSED]
- Replies: 1
- Views: 175
Molarity Formula [ENDORSED]
Can someone confirm the typical notation used for molarity? To clarify, which variables represent what?