Search found 100 matches
- Thu Mar 12, 2020 4:10 pm
- Forum: Balancing Redox Reactions
- Topic: Half Reactions
- Replies: 15
- Views: 777
Re: Half Reactions
You add H+ in acidic reaction and OH- in basic reactions and then you can determine where to add it in each equation based on where the equation is unbalanced.
- Thu Mar 12, 2020 3:59 pm
- Forum: Balancing Redox Reactions
- Topic: Determining the oxidizer and reducer
- Replies: 10
- Views: 715
Re: Determining the oxidizer and reducer
The oxidizer has a higher oxidation number and the reducer has a lower oxidation number.
- Thu Mar 12, 2020 3:15 pm
- Forum: Balancing Redox Reactions
- Topic: Test 2 Return
- Replies: 20
- Views: 1155
Re: Test 2 Return
I heard you have to go pick it up from Lavelle's mailbox or your TA. It would probably be best to email you TA to ask.
- Thu Mar 12, 2020 3:13 pm
- Forum: Balancing Redox Reactions
- Topic: Balancing basic reactions
- Replies: 8
- Views: 541
Re: Balancing basic reactions
You have to analyze the equations figure out which side needs OH- or H2O in order for the entire equation to be balanced.
- Thu Mar 12, 2020 3:09 pm
- Forum: First Order Reactions
- Topic: Half Life
- Replies: 8
- Views: 505
Re: Half Life
When you derive the half life, the initial concentration will cancel out in that equation so therefore initial concentration makes no difference in first order reactions.
- Sun Mar 08, 2020 2:10 pm
- Forum: Method of Initial Rates (To Determine n and k)
- Topic: factors that affect k
- Replies: 8
- Views: 688
Re: factors that affect k
Factors that can affect k include cell potential and temperature.
- Sun Mar 08, 2020 2:07 pm
- Forum: First Order Reactions
- Topic: Graph
- Replies: 9
- Views: 705
Re: Graph
If it is a first order reaction, the graph should be linear.
- Sun Mar 08, 2020 2:07 pm
- Forum: First Order Reactions
- Topic: Rate Law
- Replies: 4
- Views: 626
Re: Rate Law
The syllabus says you need to know how to do so but it isn't very likely that it will actually be asked on the final.
- Sun Mar 08, 2020 2:05 pm
- Forum: First Order Reactions
- Topic: order of reaction equations
- Replies: 6
- Views: 483
Re: order of reaction equations
I don't think you will be asked derive the integrated rate law.
- Sun Mar 08, 2020 2:02 pm
- Forum: First Order Reactions
- Topic: rate constants
- Replies: 30
- Views: 1373
Re: rate constants
Yes, rate constants are always positive because they represent concentration and concentration has to always be positive.
- Mon Feb 24, 2020 12:38 pm
- Forum: Balancing Redox Reactions
- Topic: Determining direction of flow
- Replies: 15
- Views: 757
Re: Determining direction of flow
Electrons always flow from the anode to the cathode, or from left to right.
- Mon Feb 24, 2020 12:30 pm
- Forum: Balancing Redox Reactions
- Topic: spontaneous
- Replies: 15
- Views: 759
Re: spontaneous
The reduction is spontaneous when the standard reduction potential is positive.
- Mon Feb 24, 2020 12:28 pm
- Forum: Balancing Redox Reactions
- Topic: Balancing Redox EQs
- Replies: 10
- Views: 633
Re: Balancing Redox EQs
It depends on the solution; if it is acidic add H+ and if basic then add OH-.
- Mon Feb 24, 2020 12:26 pm
- Forum: Balancing Redox Reactions
- Topic: Potential Difference
- Replies: 5
- Views: 419
Re: Potential Difference
A potential difference is the amount of energy required to change the electrical charge of an object.
- Mon Feb 24, 2020 12:23 pm
- Forum: Balancing Redox Reactions
- Topic: Half reactions
- Replies: 17
- Views: 832
Re: Half reactions
Half reactions are balanced when there are the same number of electrons on the products and reactants between two half equations.
- Tue Feb 18, 2020 9:21 pm
- Forum: Ideal Gases
- Topic: R Constant
- Replies: 26
- Views: 1127
Re: R Constant
You can decide which form of R to use based on what the units of the given values are.
- Tue Feb 18, 2020 9:11 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: X is to small
- Replies: 8
- Views: 471
Re: X is to small
K will always be given when solving for x or else there would be no way for us to find x.
- Tue Feb 18, 2020 9:10 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: Quadratic Equation
- Replies: 5
- Views: 433
Re: Quadratic Equation
We used the quadratic equation to solve for x when we are given the starting values and want to find the equilibrium concentrations. Once we get the equation ax^2+bx+c, we can plug in the appropriate values into the quadratic equation.
- Tue Feb 18, 2020 9:09 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: Cubic to quadratic function
- Replies: 4
- Views: 412
Re: Cubic to quadratic function
You can simplify a cubic equations if the K value is less than 10^-3 which might result in a quadratic equation or an easier equation to solve for x.
- Tue Feb 18, 2020 9:06 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: Adding Inert Gas
- Replies: 20
- Views: 1051
Re: Adding Inert Gas
Adding an inert gas will change the pressure of the system but not the K or Q value of the reaction.
- Mon Feb 10, 2020 5:33 pm
- Forum: Calculating Standard Reaction Entropies (e.g. , Using Standard Molar Entropies)
- Topic: Why is delta U = 0 for isothermal reactions?
- Replies: 11
- Views: 4219
Re: Why is delta U = 0 for isothermal reactions?
Delta U is zero for isothermal reactions because the internal energy of the system does not change.
- Mon Feb 10, 2020 5:32 pm
- Forum: Calculating Standard Reaction Entropies (e.g. , Using Standard Molar Entropies)
- Topic: Is spontaneity determined by entropy or free energy?
- Replies: 9
- Views: 1897
Re: Is spontaneity determined by entropy or free energy?
Spontaneity is determined by Gibbs free energy and whether that value is positive or negative.
- Mon Feb 10, 2020 5:31 pm
- Forum: Calculating Standard Reaction Entropies (e.g. , Using Standard Molar Entropies)
- Topic: State of molecules
- Replies: 3
- Views: 202
Re: State of molecules
Yes, the standard entropy of reaction does depend on the state of the molecule.
- Mon Feb 10, 2020 5:30 pm
- Forum: Calculating Standard Reaction Entropies (e.g. , Using Standard Molar Entropies)
- Topic: What is residual entropy?
- Replies: 16
- Views: 4788
Re: What is residual entropy?
Residual entropy is the difference in entropy between a non-equilibrium state and crystal state of a substance close to absolute zero.
- Mon Feb 10, 2020 5:28 pm
- Forum: Calculating Standard Reaction Entropies (e.g. , Using Standard Molar Entropies)
- Topic: Negative entropies
- Replies: 3
- Views: 151
Re: Negative entropies
I don't think it would be possible to have a negative entropy, it is always positive.
- Tue Feb 04, 2020 10:54 pm
- Forum: Phase Changes & Related Calculations
- Topic: State functions
- Replies: 7
- Views: 432
Re: State functions
A state function is a property where the value does not depend on the path taken to reach that specific value. Therefore, state functions can be added or subtracted to find the answer.
- Tue Feb 04, 2020 10:52 pm
- Forum: Phase Changes & Related Calculations
- Topic: about system and surroundings
- Replies: 8
- Views: 355
Re: about system and surroundings
The system is the object that is of interest and the surrounding is anything else that might be involved in the experiment.
- Tue Feb 04, 2020 10:50 pm
- Forum: Phase Changes & Related Calculations
- Topic: Heating Curve
- Replies: 6
- Views: 976
Re: Heating Curve
The slopes of the curves are the period of times where it is in its specific phase but the flat area of the graph is when the substance is changing from one phase to the next.
- Tue Feb 04, 2020 10:49 pm
- Forum: Phase Changes & Related Calculations
- Topic: phase changes, temperature constant?
- Replies: 11
- Views: 577
Re: phase changes, temperature constant?
The temperature of the sample remains constant even though heat is being supplied because all the energy is being used to change the substance phase, not alter the temperature of the sample.
- Tue Feb 04, 2020 10:47 pm
- Forum: Phase Changes & Related Calculations
- Topic: sig figs
- Replies: 2
- Views: 99
Re: sig figs
I think when we add or subtract, it's dependent on the place of the number. So, since the last significant figure it in the tens place for 340, the answer would have the last significant in the tens place.
- Thu Jan 30, 2020 9:50 pm
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: Types of Systems
- Replies: 4
- Views: 262
Re: Types of Systems
A closed system example could be a sealed beaker of water or a cold pack.
- Thu Jan 30, 2020 9:48 pm
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: State Property
- Replies: 6
- Views: 211
Re: State Property
Yes "U" is a state property because it does not depend on how the system got from the initial to the final state.
- Thu Jan 30, 2020 9:47 pm
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: state functions and properties
- Replies: 11
- Views: 5937
Re: state functions and properties
A state function is a property that depends only on the current state of the system and is independent of how that state was prepared. Examples can include internal energy, pressure, volume, temperature, and density.
- Thu Jan 30, 2020 9:45 pm
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: Isolated Systems
- Replies: 5
- Views: 257
Re: Isolated Systems
In an isolated system, a reaction can still take place inside the system but it doesn't have any effect on the outside world. Therefore, changes in the system can still be observed, recorded and calculated.
- Thu Jan 30, 2020 9:44 pm
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: Closed vs isolated systems
- Replies: 24
- Views: 845
Re: Closed vs isolated systems
A closed system is any system where energy can be exchanged with its surroundings. An example of this would be a sealed beaker of water. On the other hand, an isolated system nothing can be exchanged with their surroundings and an example of this would be combustion of glucose in a bomb calorimeter.
- Wed Jan 22, 2020 11:23 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: Calculating K
- Replies: 15
- Views: 709
Re: Calculating K
K can only be used when you know that the reaction is at equilibrium. Therefore, if the unbalanced equation is at equilibrium, simply balance the equation and then you can find K.
- Wed Jan 22, 2020 11:22 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: Q and K
- Replies: 8
- Views: 575
Re: Q and K
K is used when the reaction is at equilibrium but Q is used at anytime during the experiment. Oftentimes, the Q and K values can be compared to see whether the reaction favors the reactant or the products.
- Wed Jan 22, 2020 11:20 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: X was ignored
- Replies: 27
- Views: 1003
Re: X was ignored
If the Ka or Kb is less than 10^-3, then the x on the bottom can be ignored because the x value will be so small that it won't make a big difference to the original concentration.
- Wed Jan 22, 2020 11:19 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: suggestions
- Replies: 16
- Views: 535
Re: suggestions
I usually watch Khan Academy or Organic Chemistry Tutor but the Organic Chemistry Tutor videos tend to be on the longer side, so Khan Academy might be more helpful if you are short on time.
- Wed Jan 22, 2020 11:18 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: H20 in the ICE table
- Replies: 26
- Views: 1405
Re: H20 in the ICE table
In addition to leaving out water, you should also leave out solids and liquids in the ICE table.
- Wed Jan 15, 2020 4:07 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: Reaction Quotient
- Replies: 11
- Views: 280
Re: Reaction Quotient
The reaction quotient is the ratio of products to reactants at any time during the experiment but K is the ratio of products to reactants at equilibrium only. The reaction quotient will often tell you if the reaction is at equilibrium or which side (left or right) it favors.
- Wed Jan 15, 2020 4:05 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: How to make ICE box
- Replies: 17
- Views: 1222
Re: How to make ICE box
When you look at the balanced equation, the number of moles of each compound will tell you the change. For example if there is two moles of water the change would be 2x. The positive and negative depends on what compound you start out with. If you are given the amount of reactant and water is a prod...
- Wed Jan 15, 2020 4:03 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: Calculating Q
- Replies: 16
- Views: 723
Re: Calculating Q
We include aqueous solutions because Q is calculate the same way as K and K includes aqueous solutions.
- Wed Jan 15, 2020 3:59 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: Reaction shifts right or left?
- Replies: 14
- Views: 1498
Re: Reaction shifts right or left?
Yes, when a reaction shifts to the left, it favors the reactants and when it shifts to the right it favors the products.
- Wed Jan 15, 2020 3:57 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Writing K for heterozygous reactions
- Replies: 5
- Views: 169
Re: Writing K for heterozygous reactions
If there is an equation with liquids and gases in either the products or reactants side, only the gases are included in the Kc equation.
- Thu Jan 09, 2020 1:08 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: K expression
- Replies: 6
- Views: 170
Re: K expression
Solids and liquids are not counted in the equilibrium constant because the concentration does not change in between the products or reactants.
- Thu Jan 09, 2020 1:07 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Value of Kc and Kp
- Replies: 6
- Views: 180
Re: Value of Kc and Kp
Yes, the equilibrium constant should be the same regardless if we calculate it using the equilibrium concentrations or the equilibrium pressures.
- Thu Jan 09, 2020 1:05 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: solids/liquids
- Replies: 4
- Views: 148
Re: solids/liquids
Solids and liquids are not counted in the equilibrium constant because the concentration does not change in either the products or reactants. Therefore, yes only gases and aqueous solutions are included when trying to find K.
- Thu Jan 09, 2020 1:04 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: units of K
- Replies: 10
- Views: 484
Re: units of K
When you are finding the K, the units of the products and reactants are either all molarity, partial pressure, etc so all the units will cancel out when K is found.
- Thu Jan 09, 2020 1:02 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: K values
- Replies: 4
- Views: 187
Re: K values
If the K value is between 10⁻³ and 10³ then it SLIGHTLY favors either the product or reactant, depending on if it is bigger or smaller than one.
- Sun Dec 08, 2019 5:00 pm
- Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
- Topic: Negative pH
- Replies: 5
- Views: 331
Re: Negative pH
When a pH is less than one, that means the concentration of H+ ions is greater than one.
- Sun Dec 08, 2019 4:59 pm
- Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
- Topic: pH sig figs
- Replies: 11
- Views: 614
Re: pH sig figs
Yes, for pH sig figs, only the values after the decimal place count.
- Sun Dec 08, 2019 4:58 pm
- Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
- Topic: pH Calculation
- Replies: 3
- Views: 201
Re: pH Calculation
For any strong acid, you can just take the negative log of the molarity of the HCL to find the pH.
- Sun Dec 08, 2019 4:56 pm
- Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
- Topic: Weak Acids
- Replies: 4
- Views: 207
Re: Weak Acids
Weak acids don't completely ionize in a solution. All the H+ ions will not separate from the molecules whereas in a strong acid they will.
- Sun Dec 08, 2019 4:51 pm
- Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
- Topic: negative pH
- Replies: 4
- Views: 321
Re: negative pH
A negative pH doesn't happen to often but if you run into a problem with a negative pH then it means that the concentration of hydrogen ions is more than one.
- Tue Nov 26, 2019 5:23 pm
- Forum: Lewis Acids & Bases
- Topic: HCl vs HF
- Replies: 19
- Views: 1316
Re: HCl vs HF
The more electronegative an element is, the less acidic it will be when bonded with a hydrogen. Higher acidity molecules will be more likely to give off hydrogen atoms and less electronegative elements are less likely to do so. Therefore, since CL is less electronegative than F, it is more acidic an...
- Tue Nov 26, 2019 5:15 pm
- Forum: Lewis Acids & Bases
- Topic: Acid and Base Strength
- Replies: 7
- Views: 394
Re: Acid and Base Strength
Strong acids and bases will completely dissociate in water whereas weak bases and acids only partially dissociate in water. However, it might be easier to just memorize strong acids and bases in order to identify between the two.
- Tue Nov 26, 2019 5:13 pm
- Forum: Lewis Acids & Bases
- Topic: Proton acceptor and proton donor?
- Replies: 33
- Views: 2039
Re: Proton acceptor and proton donor?
Proton acceptors are known as bases and proton donors are acids.
- Tue Nov 26, 2019 5:12 pm
- Forum: Lewis Acids & Bases
- Topic: identification of acid/base
- Replies: 2
- Views: 186
Re: identification of acid/base
Adding the charge is helpful because then you can identify when a molecule has given up an electron/ hydrogen molecule or received one.
- Tue Nov 26, 2019 5:10 pm
- Forum: Lewis Acids & Bases
- Topic: Strong Acids
- Replies: 8
- Views: 571
Re: Strong Acids
I would try to remember all the strong acids, just in case, seeing as there isn't too many to memorize.
- Thu Nov 21, 2019 2:23 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: XA2E2
- Replies: 9
- Views: 415
Re: XA2E2
For the VSEPR formula XA2E2 it would be called bent.
- Thu Nov 21, 2019 2:23 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Polar vs. Nonpolar
- Replies: 6
- Views: 282
Re: Polar vs. Nonpolar
I think it would still be considered polar because the two Cl and the two H have different electronegativity values so the charges don't all cancel each other out.
- Thu Nov 21, 2019 2:20 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Test 2
- Replies: 7
- Views: 509
Re: Test 2
I believe you can just say the structure is bent.
- Thu Nov 21, 2019 2:17 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: tetrahedral vs. trigonal pyramidal
- Replies: 4
- Views: 361
Re: tetrahedral vs. trigonal pyramidal
No tetraderal and trigonal pyramidal are not the same. Tetradral has four bonding pair and zero lone pairs whereas trigonal pyramidal has three bonding pairs and one lone pair.
- Thu Nov 21, 2019 2:14 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Bond Angle of bent
- Replies: 17
- Views: 1237
Re: Bond Angle of bent
The bond angle of bent should be about 104.5 degrees.
- Tue Nov 12, 2019 5:16 pm
- Forum: Bond Lengths & Energies
- Topic: Boiling and Melting points
- Replies: 8
- Views: 390
Re: Boiling and Melting points
I don't think you need to know the specific boiling and melting points of each type of interaction but just know how the interaction affect the boiling and melting points and which ones might have higher or lower boiling and melting points.
- Tue Nov 12, 2019 4:44 pm
- Forum: Resonance Structures
- Topic: Point of Resonance Structures
- Replies: 2
- Views: 186
Re: Point of Resonance Structures
Even though the structures we draw don't exist, finding the Lewis structure most similar to the actual molecule allows us to better see what the molecule might look like and how strong and how long the bonds are between each element.
- Tue Nov 12, 2019 4:35 pm
- Forum: Resonance Structures
- Topic: Writing Out Resonance
- Replies: 3
- Views: 220
Re: Writing Out Resonance
I think if you need to express resonance, the teacher is asking you to draw out all possible resonance structures.
- Tue Nov 12, 2019 4:31 pm
- Forum: Lewis Structures
- Topic: Xenon
- Replies: 4
- Views: 734
Re: Xenon
Any element in period 3 or beyond has access to their respective d orbital so they are able to have/ accept extra electrons and put it in their empty d orbital.
- Tue Nov 12, 2019 4:23 pm
- Forum: Dipole Moments
- Topic: 3F.3
- Replies: 5
- Views: 305
Re: 3F.3
Dipole-dipole interactions are only important for CH3Cl, CH2Cl2, and CHCl3 because these molecules are polar whereas CH4 and CCl4 are nonpolar. Only polar molecules have dipole-dipole moments so it is only significant for those three molecules.
- Wed Nov 06, 2019 11:47 pm
- Forum: Resonance Structures
- Topic: Bond lengths
- Replies: 11
- Views: 367
Re: Bond lengths
The bond lengths are the same value because the actual structure is a mixture of all the different versions of the resonance structure. Therefore, it isn't just one that has a double bond and the rest a single bond but all the bonds are a mixture of both, making the bond length in between the value ...
- Wed Nov 06, 2019 11:43 pm
- Forum: Bond Lengths & Energies
- Topic: Why Are Double Bonds Shorter
- Replies: 16
- Views: 6050
Re: Why Are Double Bonds Shorter
Double bonds are shorter than single bonds because double bonds are stronger and therefore pull the electrons closer together in the two elements which decreases the length of the bond.
- Wed Nov 06, 2019 11:41 pm
- Forum: Bond Lengths & Energies
- Topic: Midterm
- Replies: 9
- Views: 477
Re: Midterm
It should take about a week for the midterm to be graded.
- Wed Nov 06, 2019 11:41 pm
- Forum: Bond Lengths & Energies
- Topic: Bond lengths
- Replies: 4
- Views: 154
Re: Bond lengths
Bond length is dependent on the type of bond, whether it is a single bond, double bond, or triple bond. Then if each molecule has resonance the bond lengths will be in between the lengths of the two different bonds. We have not been taught how to specifically find the exact value of the bond length.
- Wed Nov 06, 2019 11:38 pm
- Forum: Bond Lengths & Energies
- Topic: Midterm
- Replies: 8
- Views: 457
Re: Midterm
There are supposed to be eight questions on the midterm but there are multiple parts to each question.
- Wed Oct 30, 2019 3:19 pm
- Forum: Octet Exceptions
- Topic: Radicals
- Replies: 9
- Views: 324
Re: Radicals
In order to identify if a species is a radical, just count the total number of valence electrons in that molecule and if it is an odd number, it is a radical.
- Wed Oct 30, 2019 3:13 pm
- Forum: Lewis Structures
- Topic: Bonds:
- Replies: 3
- Views: 106
Re: Bonds:
Each bond line is two electrons shared between elements.
- Wed Oct 30, 2019 3:12 pm
- Forum: Octet Exceptions
- Topic: Can P,S,Cl have less than 8 electrons?
- Replies: 3
- Views: 165
Re: Can P,S,Cl have less than 8 electrons?
Usually P, S, and Cl don't have less than eight electrons because they are not stable until they complete their octet or exceed it. Therefore, while it is unstable, it will always be trying to react with other elements until it becomes stable.
- Wed Oct 30, 2019 3:10 pm
- Forum: Ionic & Covalent Bonds
- Topic: Format of midterm?
- Replies: 12
- Views: 641
Re: Format of midterm?
Like our first test, I'm pretty sure the test will all be free response because the practice midterm given to us by the UA's is also all free responses.
- Wed Oct 30, 2019 3:06 pm
- Forum: Ionic & Covalent Bonds
- Topic: Likely Charge for Ions to Form
- Replies: 3
- Views: 244
Re: Likely Charge for Ions to Form
The most likely charge for an atom to form is based on the number of valence electrons of each element. For example, Na has one valence electron so it would be more likely to give that one electron up than try and collect seven more. Therefore it has a likely charge of +1. On the other hand, P has f...
- Tue Oct 22, 2019 9:47 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Electron Configuration
- Replies: 4
- Views: 134
Re: Electron Configuration
Adding x, y, or z states specifically the orientation of the orbital and where it lies on a 3D (x,y,z) graph.
- Tue Oct 22, 2019 9:44 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Electron Spin
- Replies: 8
- Views: 475
Re: Electron Spin
When you are filling out an orbital, know that each orbital must have one electron before the electrons are paired. This is because electrons prefer to be in different orbitals due to their negative charge that repels other electrons. So for example, if four electrons are in the p orbital there woul...
- Tue Oct 22, 2019 9:41 pm
- Forum: Quantum Numbers and The H-Atom
- Topic: The plus and minus sign on the magnetic quantum #
- Replies: 5
- Views: 188
Re: The plus and minus sign on the magnetic quantum #
You should write the plus sign just to signify specifically which way the electron is spinning.
- Tue Oct 22, 2019 9:39 pm
- Forum: Quantum Numbers and The H-Atom
- Topic: 1D.13
- Replies: 3
- Views: 198
Re: 1D.13
So because you know it is the d orbital, you know l= 2. To determine the ml value, know that ml equals the range of value from -l to l. Therefore, in this case, the values of ml would be -2, -1, 0, 1, and 2.
- Tue Oct 22, 2019 9:36 pm
- Forum: Quantum Numbers and The H-Atom
- Topic: Electrostatic potential energy
- Replies: 3
- Views: 175
Re: Electrostatic potential energy
In this equation, q1 and q2 is the value of the charge of the two electrons.
- Tue Oct 15, 2019 6:12 pm
- Forum: Properties of Light
- Topic: Homework
- Replies: 11
- Views: 472
Re: Homework
Yes, you will still receive full credit, as long as they are all problems that were assigned based on the syllabus.
- Tue Oct 15, 2019 6:10 pm
- Forum: Properties of Light
- Topic: MidTerms and Finals
- Replies: 11
- Views: 392
Re: MidTerms and Finals
Both the midterms and finals will be administered at a different time than lecture and discussion times. For example, the midterm is from 6PM - 8PM on Novemebr 6.
- Tue Oct 15, 2019 6:08 pm
- Forum: Einstein Equation
- Topic: E=hv [ENDORSED]
- Replies: 52
- Views: 18096
Re: E=hv [ENDORSED]
The E represents the amount of energy of a photon but you can always compare that E value to the work function value to determine whether the E amount is enough to remove the electron from one shell to another.
- Tue Oct 15, 2019 6:05 pm
- Forum: Properties of Electrons
- Topic: Photons
- Replies: 9
- Views: 293
Re: Photons
Yes, there can be cases where the photons do not have enough energy to eject an electron. If there is not enough energy, then the electron will stay in whatever orbital it is currently in and will not jump to the other orbitals.
- Tue Oct 15, 2019 6:03 pm
- Forum: Heisenberg Indeterminacy (Uncertainty) Equation
- Topic: Time of Use
- Replies: 5
- Views: 88
Re: Time of Use
For questions that require you to use Heisenberg equation, the question will have the words uncertainty in position, velocity, or momentum. If these words are not stated in the question, then you should not use Heisenberg's equation.
- Thu Oct 10, 2019 2:00 pm
- Forum: Properties of Light
- Topic: Atom's transition
- Replies: 3
- Views: 126
Re: Atom's transition
A greater energy difference implies greater frequency because energy and frequency are proportional to each other. As one increases, the other does as well and vice versa based on the equation E = hv.
- Thu Oct 10, 2019 1:55 pm
- Forum: DeBroglie Equation
- Topic: DeBroglie Units
- Replies: 3
- Views: 611
Re: DeBroglie Units
You also need to remember that you are dividing Planck's constant by the momentum and the units for Plank's constant is J(s) where Joules is kg⋅m2⋅s−2. So, in order for the two masses units to cancel out, you have to use kg in the denominator as well. It's always about using the same units as the co...
- Thu Oct 10, 2019 1:50 pm
- Forum: Properties of Electrons
- Topic: Balmer/Lyman series
- Replies: 5
- Views: 265
Re: Balmer/Lyman series
I think that's something you should get familiar with. Especially the Balmer and Lyman series since Lavelle specifically went over those two in class.
- Thu Oct 10, 2019 1:48 pm
- Forum: Properties of Light
- Topic: Question 1.A.3
- Replies: 4
- Views: 253
Re: Question 1.A.3
The extent of the change in the electrical field is referring to the slope of the waves and so as the frequency decreases, the waves of would be broader and more spread out, therefore meaning that the slopes of the waves would be less steep. This decrease in the slope means that the extent of the ch...
- Mon Oct 07, 2019 10:33 pm
- Forum: Photoelectric Effect
- Topic: Post Module Assessment
- Replies: 1
- Views: 91
Post Module Assessment
For number 25, it states that the photoelectric experiments gave rise to a new equation relating the energy of light to its frequency. Select the right equation.
A. c = λ x v
B. Ek = 1/2(MV²)
C. MV²/2 = hv - φ
D. E = hv
E. None of the above
Which one is the correct answer? Thank you!
A. c = λ x v
B. Ek = 1/2(MV²)
C. MV²/2 = hv - φ
D. E = hv
E. None of the above
Which one is the correct answer? Thank you!
- Wed Oct 02, 2019 1:07 am
- Forum: Significant Figures
- Topic: Lecture on Sig Figs?
- Replies: 4
- Views: 201
Lecture on Sig Figs?
Hey everyone! I heard that there would be a lecture that includes sig figs, does anyone know if this is true or should I just go ahead and review it on my own?
- Wed Oct 02, 2019 1:03 am
- Forum: Balancing Chemical Reactions
- Topic: Why do we balance chemical equations?
- Replies: 13
- Views: 8378
Re: Why do we balance chemical equations?
According to the law of conservation of mass, during a chemical reaction, mass is neither created or destroyed so the equation must be balanced in order to follow this law.
- Wed Oct 02, 2019 1:02 am
- Forum: SI Units, Unit Conversions
- Topic: Textbook
- Replies: 7
- Views: 229
Re: Textbook
I think you can leave the textbook at home since often times during lecture we are taking notes off of Dr. Lavelle's powerpoints. The textbook is probably just helpful for the homework or for supplementary knowledge if something in the lecture was confusing for you.
- Wed Oct 02, 2019 1:01 am
- Forum: Accuracy, Precision, Mole, Other Definitions
- Topic: Avogadro's Number [ENDORSED]
- Replies: 12
- Views: 782
Re: Avogadro's Number [ENDORSED]
If I am not mistaken, you use Avogadro's Number to find the number of atoms, molecules, or formula units when you are given the number of moles of any substance.
- Wed Oct 02, 2019 12:58 am
- Forum: Significant Figures
- Topic: Rounding the elements
- Replies: 12
- Views: 806
Re: Rounding the elements
I personally round it to the hundredth place of the decimal place and it usually gets me the same answer as the answer in the solutions manual so that should work but I guess the safest option would be using all the values in the periodic table.