Search found 66 matches
- Wed Mar 13, 2019 3:23 pm
- Forum: Third Law of Thermodynamics (For a Unique Ground State (W=1): S -> 0 as T -> 0) and Calculations Using Boltzmann Equation for Entropy
- Topic: Boltzmann Equation
- Replies: 3
- Views: 738
Re: Boltzmann Equation
Like said above, microstates and talk about degeneracy should indicate that the Boltzmann equation would be at play.
- Wed Mar 13, 2019 3:22 pm
- Forum: Calculating Work of Expansion
- Topic: Reversible vs irreversible
- Replies: 6
- Views: 873
Re: Reversible vs irreversible
Reversible expansion will always do more work. It is also clear to make this distinction by looking at some of the graphs and the area underneath the curve when comparing reversible and irreversible expansion.
- Wed Mar 13, 2019 3:18 pm
- Forum: Student Social/Study Group
- Topic: Studying for the Final
- Replies: 25
- Views: 2705
Re: Studying for the Final
Also, the UA's post worksheets here and its really helpful to review those on the topics we covered throughout the quarter. The review sessions are also really helpful because they usually cover past exam problems.
- Wed Mar 06, 2019 10:57 pm
- Forum: First Order Reactions
- Topic: Exponential Curve
- Replies: 6
- Views: 630
Re: Exponential Curve
This exponential curve is modeled as a linear function because of the ln[A] on the left side of the equation. If you were to solve this equation for just [A], you would see that the function would be a decreasing exponential curve. Since the left is not solving for [A] and is in terms of ln[A], this...
- Wed Mar 06, 2019 10:55 pm
- Forum: General Rate Laws
- Topic: Deriving Rate Laws
- Replies: 3
- Views: 393
Re: Deriving Rate Laws
Usually for exams, deriving equations, such as rate laws, is fair test material. Also, it is helpful and a bit easier to know how to use them if you know where they come from and how to derive them.
- Wed Mar 06, 2019 10:54 pm
- Forum: Kinetics vs. Thermodynamics Controlling a Reaction
- Topic: how is kinetics different?
- Replies: 17
- Views: 1596
Re: how is kinetics different?
Like the other responses, thermodynamics gives no information based on time or the rate of the reaction. This information involves activation energy, which is a study included in kinetics. Kinetics focused on the rate of the reaction itself whereas thermodynamics can say if a reaction were to be spo...
- Wed Feb 27, 2019 10:41 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: 14.11
- Replies: 2
- Views: 329
Re: 14.11
Also, it is useful to refer to the equation that says Eºcell = Eºcathode - Eºanode. Since Eºcell should be positive, the more positive Eº should be denoted as the cathode and the other as the anode. Since it is - Eºanode, it is essentially flipped in this equation with all the elements switching sid...
- Wed Feb 27, 2019 10:38 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Water in Cell Diagrams
- Replies: 2
- Views: 399
Re: Water in Cell Diagrams
Like said above, in most cases, water is not included. Since it is not used to necessarily balance charges and is not being reduced or oxidized, it does not need to be in the cell diagram. Since the other parts of the diagram are indicated as aqueous, water can be assumed to be present.
- Tue Feb 26, 2019 10:36 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Moles of electrons?
- Replies: 6
- Views: 554
Re: Moles of electrons?
Like stated above, if the redox reaction that is given is already balanced, you can just look at either half-reaction to see how many electrons cancel out since everything is already properly balanced.
- Tue Feb 19, 2019 8:25 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Test 3
- Replies: 10
- Views: 943
Re: Test 3
Also, on Professor Lavelle's website there is a specific announcement that explains what will be covered on the test.
- Tue Feb 19, 2019 8:14 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Factors
- Replies: 2
- Views: 258
Re: Factors
Like said above, if you look at the individual factors that determine what delta G is in the equations, inferences can be made such as higher temperatures leading to a greater chance of a reaction being spontaneous or a negative enthalpy change.
- Tue Feb 19, 2019 7:21 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Delta G a state function?
- Replies: 23
- Views: 2749
Re: Delta G a state function?
Delta G, or just Gibbs free energy, is a state function. This means that you can apply the properties state functions have such as the properties you use for enthalpy and entropy.
- Wed Feb 13, 2019 3:26 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Midterm
- Replies: 4
- Views: 542
Re: Midterm
It probably would be helpful to be aware of the strong acids and bases and realize that these are 100% dissociated in water.
- Wed Feb 13, 2019 3:25 pm
- Forum: Calculating Work of Expansion
- Topic: Hotdog Midterm #6
- Replies: 2
- Views: 354
Re: Hotdog Midterm #6
This reasoning would be correct for state functions like delta S (entropy) and delta U (internal energy). However, w (work) and heat (q) are path functions and are not just dependent on starting and end values.
- Wed Feb 13, 2019 3:21 pm
- Forum: Entropy Changes Due to Changes in Volume and Temperature
- Topic: delta S
- Replies: 7
- Views: 718
Re: delta S
Like the replies above, delta S of the universe, or when negative delta S of the system is equal to delta S of the surroundings, is 0 when the reaction is at equilibrium and is reversible. Also, delta U would be 0.
- Tue Feb 05, 2019 9:33 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Cv vs Cp
- Replies: 3
- Views: 421
Re: Cv vs Cp
Like said before, when there is a constant volume, energy cannot be released through work. Therefore, the heat capacity at constant pressure is higher because this added energy through heat can be given off through work and expansion.
- Tue Feb 05, 2019 9:30 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Important Thermochemistry Equations
- Replies: 3
- Views: 405
Re: Important Thermochemistry Equations
Also, it is helpful to know which equations apply for which problems so that your time is used efficiently to understand and set up the problems. Make sure you know the general equations needed to solve different problems (specific heat capacity, internal energy, constant volume/pressure, etc.).
- Tue Feb 05, 2019 9:28 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: 6th edition 8.51
- Replies: 2
- Views: 317
Re: 6th edition 8.51
Also, in order to find the energy density per liter, you have to multiply the density which is given by 1.65g/cm^3 by 10^3cm^3/L so your answer and units are correct.
- Wed Jan 30, 2019 7:22 pm
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: open, closed, isolated
- Replies: 4
- Views: 492
Re: open, closed, isolated
For thermodynamics, a system should always be able to fit one of these three descriptions. However, for isolated systems, these are typically a lot harder to replicate in nature or in labs because its hard to make sure no energy or matter can get in or out. Examples like a thermos that is insulated ...
- Wed Jan 30, 2019 7:17 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Homework
- Replies: 9
- Views: 883
Re: Homework
Like everyone else said, I also had to jump around the 6th edition to find problems that related to the lecture order. However, if you read or skim through the chapter then it isn't too hard to do the earlier homework problems on work, etc.
- Tue Jan 29, 2019 3:30 pm
- Forum: Phase Changes & Related Calculations
- Topic: temperature
- Replies: 3
- Views: 368
Re: temperature
Also, it is helpful to recall the graph Professor Lavelle showed during lecture that shows that the added heat is contributing to the phase change and not raising the temperature. Like said above, the energy added is going into the phase change reaction. This added heat can also be observed when dis...
- Wed Jan 23, 2019 4:25 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: ignoring x
- Replies: 16
- Views: 3218
Re: ignoring x
Also, it is important to keep in mind that x is not actually 0 because if you plug in 0 for all x's it will be impossible to solve for x. However, it is useful in approximations to make the calculations more simple as the other replies have stated.
- Wed Jan 23, 2019 4:23 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: Acids and Bases
- Replies: 6
- Views: 536
Re: Acids and Bases
For Chem 14B during the ICE tables and chemical equilibria, I believe we have been using the Bronsted acids and bases definition.
- Wed Jan 23, 2019 4:20 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Sig Figs
- Replies: 3
- Views: 408
Re: Sig Figs
Like said above, sig figs are a little bit different when dealing with pH and pOH because of what the log function does. A good rule is to just count sig figs in pH and pOH as the figures after the decimal point. This means that a pH of 1.2 has only one sigfig and 1.23 would have two. This rule only...
- Mon Jan 21, 2019 4:56 pm
- Forum: Ideal Gases
- Topic: ICE table
- Replies: 11
- Views: 1261
Re: ICE table
Like said above, you can use both when calculating for your ICE table. The thing to keep in mind though is what the question asks for in the final answer. If in partial pressures, you may be asked to convert to molarity, or concentration (n/V).
- Tue Jan 15, 2019 10:20 pm
- Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
- Topic: test 1 [ENDORSED]
- Replies: 7
- Views: 874
Re: test 1 [ENDORSED]
The test will most likely cover chemical equilibrium as well as acids and bases up to the lecture this Friday. It is also useful to refer to Outline 1 and Outline 2 on the course website to see which topics we are expected to know for the upcoming tests.
- Tue Jan 15, 2019 10:15 pm
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: "Shifting"
- Replies: 15
- Views: 1702
Re: "Shifting"
Shifting can be a confusing term because it can give the impression that the reaction is moving. In fact, "shifting," "lie to," and "favored" all mean the same thing. This term either denotes that a reaction favors the reactants or products depending on a condition. The...
- Tue Jan 15, 2019 10:12 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: 11.59
- Replies: 3
- Views: 330
Re: 11.59
For the two options, if both are positive, plug it into the ICE table and make sure that your equilibrium concentration is still positive. If x is too large then this will be negative which cannot happen. In any case, it is good to check both solutions if unsure, especially if both are positive valu...
- Tue Jan 15, 2019 10:10 pm
- Forum: Ideal Gases
- Topic: Homework for week 2 [ENDORSED]
- Replies: 10
- Views: 2948
Re: Homework for week 2 [ENDORSED]
As long as the homework problems are relevant to the content covered in lecture in the past week, you should be fine. Like said above, the main focus should probably be acids and bases as well as the ICE tables in chemical equilibria.
- Wed Jan 09, 2019 11:15 am
- Forum: Ideal Gases
- Topic: Memorization
- Replies: 12
- Views: 1189
Re: Memorization
Although these equations are given on the constants and equations sheet, it is helpful in terms of time and ease to memorize equations used often such as PV=nrT.
- Tue Jan 08, 2019 3:08 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Concentrations of products/reactants
- Replies: 6
- Views: 509
Re: Concentrations of products/reactants
K is the equilibrium constant so the numbers you use are the equilibrium concentrations of the products and reactants. This tells you that this ratio will be approached when a reaction reaches equilibrium from its initial concentrations.
- Tue Jan 08, 2019 3:04 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Concentrations
- Replies: 5
- Views: 440
Re: Concentrations
Like the replies above, it is very helpful to view these changes visually. Similarly, it's helpful to think of adding reactants or products to a reaction at equilibrium as tipping a scale or seesaw. In order to react to this increase, either the forward or reverse reaction is favored to even everyth...
- Tue Jan 08, 2019 2:57 pm
- Forum: Ideal Gases
- Topic: Pressure units
- Replies: 4
- Views: 493
Re: Pressure units
At the end of lecture, Professor Lavelle briefly stated that you should use atmosphere as the unit for partial pressure.
- Sun Dec 09, 2018 4:10 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Lost Items in Exam Rooms [ENDORSED]
- Replies: 1
- Views: 2843
Re: Lost Items in Exam Rooms [ENDORSED]
I left a bright, large blue hydroflask with stickers in the La Kretz exam room. It wasn’t there when I went back so please let me know if you’ve seen it or took it. Thank you!!
- Wed Dec 05, 2018 9:05 pm
- Forum: Bronsted Acids & Bases
- Topic: Water as an Acid or Base
- Replies: 4
- Views: 513
Re: Water as an Acid or Base
When looking at an equilibrium, it is helpful to note whether the reaction other than water is a base or acid. This tells you that water has to act the opposite in this equilibrium reaction because the water either loses a proton to donate to the base (acid) or gains a proton from the acidic donor (...
- Wed Dec 05, 2018 8:58 pm
- Forum: Dipole Moments
- Topic: Dipole Moment of C and H
- Replies: 3
- Views: 694
Re: Dipole Moment of C and H
There are diploe moments present with C and H so nothing is ignored. However, in molecules such as methane (CH4), the symmetrical tetrahedral shape has each of these dipole vectors canceling out, making the whole molecule nonpolar. These dipole moments are still in play though when considering the m...
- Tue Dec 04, 2018 1:07 pm
- Forum: Lewis Acids & Bases
- Topic: Difference between Lewis and Bronsted
- Replies: 5
- Views: 588
Re: Difference between Lewis and Bronsted
Also, it is important to note that Lewis acids and bases are more general than Bronsted acids and bases. In the textbook, it says all Bronsted acids and bases are Lewis acids and bases but not the other way around.
- Wed Nov 28, 2018 12:33 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: ionic molecule
- Replies: 3
- Views: 320
Re: ionic molecule
When listing down what intermolecular forces molecules have, just always note that London dispersion forces occur no matter what. In some molecules, this is the only force that is acting.
- Tue Nov 27, 2018 9:41 pm
- Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
- Topic: Homework Question
- Replies: 2
- Views: 375
Re: Homework Question
Also, like we learned in the past, make sure to account for formal charge and make sure the Lewis structure is the most stable possible. After, proceed with VSEPR and this should tell you all you need to answer the question.
- Tue Nov 27, 2018 9:36 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Bent and Angular
- Replies: 5
- Views: 485
Re: Bent and Angular
Professor Lavelle refers to the shape as "bent" and the textbook refers to it as "angular." Either should be accepted but I would lean toward bent for the naming since that's what Professor Lavelle has said during lecture.
- Fri Nov 23, 2018 1:28 pm
- Forum: Sigma & Pi Bonds
- Topic: formation of pi bond
- Replies: 6
- Views: 611
Re: formation of pi bond
With that, any bond formed between two atoms, the sigma bond is formed first and there can only be one, with the double and triple bonds being composed of one sigma bond and one and two pi bonds.
- Fri Nov 23, 2018 1:25 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Sixth Edition. Question 4.109
- Replies: 4
- Views: 1063
Re: Sixth Edition. Question 4.109
To reiterate, here there are 4 areas of electron density around the oxygen. The two lone pairs are not shown but have to be present to complete the octet. It is a tetrahedral configuration with the VSEPR equation of AX2E2, meaning that it is of bent shape with about a 109.5 degree angle.
- Wed Nov 21, 2018 1:19 am
- Forum: Ionic & Covalent Bonds
- Topic: Silver halides & solubility
- Replies: 2
- Views: 1098
Re: Silver halides & solubility
Moreover, this is just another example of covalent character within ionic bonds. Ions which cause large distortion, such as AlI, are described as being highly polarizable. This causes the ionic bond to have more covalent bond character.
- Wed Nov 14, 2018 1:44 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Lewis Structures/Shape
- Replies: 3
- Views: 288
Re: Lewis Structures/Shape
When it comes to molecules like this, draw the Lewis structure as instructed before. The molecular geometry, as stated above, would be different around the carbon atoms and with respect to the C-Be-C bond. According to the VSEPR model, just note the areas of electron density about these atoms.
- Wed Nov 14, 2018 1:42 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: VSEPR
- Replies: 3
- Views: 385
Re: VSEPR
Lewis structures are needed for the VSEPR model to determine the areas of electron density around the central atom (bond pairs and lone pairs). From this information obtained by drawing a Lewis structure, the molecular shape can be determined.
- Wed Nov 14, 2018 1:40 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Electron density
- Replies: 6
- Views: 615
Re: Electron density
In the VSEPR model, only refer to the central atom when talking about electron density. The presence of lone pairs on the central atom will change the molecular shape of the molecule. Note that molecular shape and electron geometry are different as electron geometry just notes the areas of electron ...
- Thu Nov 08, 2018 12:12 am
- Forum: Properties of Light
- Topic: Exam 2 Question 4A
- Replies: 6
- Views: 839
Re: Exam 2 Question 4A
As stated above, e=hv would be sufficient for this problem. The only thing you have to watch out for is converting kJ (10^3) to J. Other than that, this is the energy of a single photon so you would just multiply this number with Planck's constant and apply proper significant figures.
- Thu Nov 08, 2018 12:07 am
- Forum: Octet Exceptions
- Topic: Copper
- Replies: 10
- Views: 942
Re: Copper
Also, it has been experimentally observed that half-filled subshells are more stable than predicted. The electron configuration exception of copper allows it to have half-filled subshells making it its most stable ground state and proper electron configuration.
- Thu Nov 08, 2018 12:05 am
- Forum: Lewis Structures
- Topic: Double Bonds
- Replies: 7
- Views: 537
Re: Double Bonds
Just to reiterate, after all electrons are accounted for and single bonds are made, formal charges can then be calculated. This will indicate whether a double bond or even a triple bond should be made to lower formal charges. As you do more Lewis structures, patterns with certain elements, such as o...
- Wed Oct 31, 2018 5:04 pm
- Forum: DeBroglie Equation
- Topic: De Broglie
- Replies: 12
- Views: 1404
Re: De Broglie
Summed up, use De Broglie when dealing with anything involving a rest mass and use the light equations when dealing with photons that have no resting mass.
- Wed Oct 31, 2018 1:44 pm
- Forum: Resonance Structures
- Topic: How does a resonance structure work?
- Replies: 10
- Views: 1081
Re: How does a resonance structure work?
Another important thing to note is the formal charges present within these structures. If you are trying to determine if something has resonance, check to see if the formal charges make sense when changing a bond. For example, a formal charge of +1 for chlorine in a possible resonance hybrid is high...
- Wed Oct 31, 2018 1:38 pm
- Forum: Lewis Structures
- Topic: D orbital
- Replies: 4
- Views: 401
Re: D orbital
Since d-orbitals have 5 orbitals, they can hold 10 electrons as each orbital can have a spin up and spin down pair. This means that, with the d-orbital in play, there can be up to 18 valence electrons as s-orbitals can have 2 electrons and p-orbitals can have 6 electrons.
- Wed Oct 24, 2018 12:03 am
- Forum: Heisenberg Indeterminacy (Uncertainty) Equation
- Topic: Uncertainty of an Electron's Velocity & Speed of Light
- Replies: 4
- Views: 467
Re: Uncertainty of an Electron's Velocity & Speed of Light
The speed of light is the fastest speed that anything can go. In fact, light and photons are the only things that can travel at the speed of light. It is not physically possible for things with rest mass, like electrons, to move at or faster than this speed. Therefore, this theory is proved incorrec...
- Tue Oct 23, 2018 11:59 pm
- Forum: Properties of Light
- Topic: Electromagnetic Spectrum
- Replies: 5
- Views: 631
Re: Electromagnetic Spectrum
It would be good to know the order of the EM spectrum and that visible light is present from wavelengths of 400-700nm. The order from shortest to longest wavelength (conversely highest to lowest frequency): gamma rays, x-rays, ultraviolet, visible, infrared, microwave, radio.
- Tue Oct 23, 2018 11:54 pm
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: Nodal Planes
- Replies: 6
- Views: 542
Re: Nodal Planes
Also, if you look at the shape of an s-orbital when graphed out, you see on the axis that there are no spots on any of the axis planes where electrons cannot be present. Nodal planes denote where electrons cannot be observed, but since the s-orbital is a sphere that encompasses all the axes, there a...
- Thu Oct 18, 2018 5:00 pm
- Forum: DeBroglie Equation
- Topic: De Broglie
- Replies: 2
- Views: 354
Re: De Broglie
Also, once you apply the equation E=hc/λ to find how much energy is produced by each individual photon, multiply the energy found from this equation with the total number of photons. This will cancel photons so your final answer will just be in just joules instead of joules/photon.
- Tue Oct 16, 2018 8:30 pm
- Forum: Einstein Equation
- Topic: Units of Energy
- Replies: 5
- Views: 523
Re: Units of Energy
Also, putting Joules in terms of SI units can be especially handy when seeing if units make sense and cancel correctly. For example, in calculating wavelength for light, the kg, seconds, and one m cancel leaving your answer in m (meters).
- Tue Oct 16, 2018 8:27 pm
- Forum: Properties of Light
- Topic: Wave-Like Properties Value
- Replies: 2
- Views: 195
Re: Wave-Like Properties Value
In Lecture, Dr. Lavelle said anything less than 10^-15 or so would be undetectable, like said above. Pico as a prefix is 10^-12 so anything much smaller than that can be qualified as undetectable.
- Wed Oct 10, 2018 5:58 pm
- Forum: Significant Figures
- Topic: Repeating Decimal
- Replies: 3
- Views: 2472
Re: Repeating Decimal
Like said before, enter the fraction instead of rounding something such as 1/3 to .333 ensure a more accurate result. When it comes to rounding, try to hold off on any rounding as much as possible until you get to the final piece of data the question is asking for. Then apply the rules of sig figs.
- Tue Oct 09, 2018 10:32 pm
- Forum: Einstein Equation
- Topic: Units of Hz in Equations
- Replies: 1
- Views: 196
Units of Hz in Equations
When using Einstein's equation, given MHz, do you have to convert this to Hz for the formula to work? I just want to make sure, but I would assume so since Hz is the base unit and M is just a prefix.
- Mon Oct 08, 2018 10:19 pm
- Forum: Einstein Equation
- Topic: Einstein's Equation: E=hv
- Replies: 11
- Views: 1510
Re: Einstein's Equation: E=hv
Also, it is important and useful to know that 'E' will be in joules since that is the standard measurement of energy and is taken from Planck's constant.
- Wed Oct 03, 2018 12:24 pm
- Forum: Significant Figures
- Topic: Periodic Table Sig Figs
- Replies: 4
- Views: 1263
Re: Periodic Table Sig Figs
During the lecture today, Professor Lavelle stated that for computing and converting to moles or grams, just use the significant figures for the molar masses provided to you by the given periodic table. At the end of the problem, proceed to include the necessary significant figures. Basically, this ...
- Wed Oct 03, 2018 12:19 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 3000806
Re: Post All Chemistry Jokes Here
What do you call a fish made of two sodium atoms?
2Na (Tuna)!
2Na (Tuna)!
- Tue Oct 02, 2018 10:52 pm
- Forum: Significant Figures
- Topic: Significant Figures
- Replies: 6
- Views: 762
Re: Significant Figures
Does anybody know if you must maintain a correct number of significant figures while working out, for example, a molarity problem, or if you would simply apply the correct number of significant figures once you have found your solution? When working through a problem, I believe that rounding to mai...
- Tue Oct 02, 2018 9:26 pm
- Forum: Limiting Reactant Calculations
- Topic: Percent Yield
- Replies: 5
- Views: 937
Re: Percent Yield
When you calculate a percent yield problem, make sure to convert the limiting reactant into moles. From there, using the stoichiometric coefficients, you can calculate the moles of the theoretical yield of the product (N2H4). Since the ratio of the coefficients is 2:1, there will be half as many mol...
- Fri Sep 28, 2018 10:24 pm
- Forum: SI Units, Unit Conversions
- Topic: How does grading for discussion posts work?
- Replies: 80
- Views: 8161
Re: How does grading for discussion posts work?
Yes, I believe that you receive a point everytime you participate in the forums as either a response to a thread or posing a question. Also, I believe these are checked and marked down by your TA.