Search found 78 matches
- Sun Mar 18, 2018 9:37 am
- Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
- Topic: isothermal = no internal energy change
- Replies: 4
- Views: 753
Re: isothermal = no internal energy change
Is delta U zero for all reversible reactions or just isothermal?
- Thu Mar 15, 2018 11:38 am
- Forum: First Order Reactions
- Topic: integrated rate
- Replies: 1
- Views: 373
integrated rate
Can we only find the concentration of reactants with integrated rate laws, or is the reverse law applicable to the concentration of products?
- Wed Mar 14, 2018 10:53 pm
- Forum: First Order Reactions
- Topic: Integrated Rate Laws
- Replies: 4
- Views: 683
Re: Integrated Rate Laws
Can we only find the concentration of reactants with integrated rate laws, or is the reverse law applicable to the concentration of products?
- Wed Mar 14, 2018 9:59 pm
- Forum: First Order Reactions
- Topic: Exam question 3
- Replies: 4
- Views: 667
Re: Exam question 3
Because the rate is constant, you can assume that this rate is zero order, which mean that the rate will just equal the reaction constant. Since the rate is in units of M/s, you can set the rate equal to an amount of change in the molarity over a time interval. Then you can plug in the change in mo...
- Wed Mar 14, 2018 9:47 pm
- Forum: General Rate Laws
- Topic: rate law vs integrated rate law
- Replies: 2
- Views: 4578
rate law vs integrated rate law
What is the difference between the rate law and the integrated rate law?
- Wed Mar 14, 2018 9:46 pm
- Forum: General Rate Laws
- Topic: Test 3 #3
- Replies: 1
- Views: 270
Re: Test 3 #3
The rate of C2 gas consumption in this reaction is constant throughout and is given as 0.250 M/s. If you reaction vessel starts with 0.35M of ABC, how long will it take to get to 24.00M of ABC? The equation give is AB+C-->ABC. Can someone explain how they did this please. You basically balance the ...
- Wed Mar 14, 2018 9:40 pm
- Forum: General Rate Laws
- Topic: Rate Law
- Replies: 6
- Views: 1148
Rate Law
So if given a chemical equation, does the coefficient in front of the reactant automatically translate into the exponent in the rate law? So 2NO as a reactant would have a rate law = k[NO]^2?
- Wed Mar 14, 2018 8:37 pm
- Forum: First Order Reactions
- Topic: Exam question 3
- Replies: 4
- Views: 667
Exam question 3
The rate of A2 gas consumption in this reaction is constant throughout and is given as .550 M/s. If your reaction vesset starts witih .45 M of AC how long will it tkae to get to 36.00M of AC?
A2+BC = AC + B2
How do you do this question?
A2+BC = AC + B2
How do you do this question?
- Thu Mar 08, 2018 11:07 am
- Forum: General Rate Laws
- Topic: Rate Constant k
- Replies: 6
- Views: 786
Rate Constant k
Can someone explain what exactly is the rate constant?
- Wed Mar 07, 2018 9:55 pm
- Forum: Arrhenius Equation, Activation Energies, Catalysts
- Topic: 15.61
- Replies: 1
- Views: 293
15.61
How do you solve question 61?
- Mon Feb 26, 2018 11:00 pm
- Forum: Method of Initial Rates (To Determine n and k)
- Topic: 5.13
- Replies: 2
- Views: 401
5.13
Can someone explain 5.13 and how to get the initial reaction rate?
- Mon Feb 26, 2018 10:42 pm
- Forum: General Rate Laws
- Topic: Unique rate of reaction Hw 15.3
- Replies: 4
- Views: 938
Re: Unique rate of reaction Hw 15.3
So what is the unique rate of reaction for Hw 15.3 part c? There is no answer in the textbook.
- Mon Feb 26, 2018 10:34 pm
- Forum: Kinetics vs. Thermodynamics Controlling a Reaction
- Topic: Textbook Problems 15.3 and 15.5
- Replies: 7
- Views: 1072
Re: Textbook Problems 15.3 and 15.5
How come the textbook answer for 15.3 part a) is 6.5 x 10^-3 mol/L*s? Why did they not divide by the number of moles (2)?
- Mon Feb 26, 2018 10:29 pm
- Forum: General Rate Laws
- Topic: Homework Help 15.1
- Replies: 4
- Views: 2580
Re: Homework Help 15.1
Can someone explain part b and c too?
- Thu Feb 22, 2018 10:10 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: 14.41
- Replies: 4
- Views: 820
Re: 14.41
When would you use the equation with E=E-RT/NF lnQ vs E=E-.05916V/N logQ?
- Thu Feb 22, 2018 10:44 am
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: 14.19
- Replies: 2
- Views: 353
Re: 14.19
If CU2+/Cu is .34 volts then wouldn't the reverse reaction where copper loses electrons be -.34?
- Wed Feb 21, 2018 11:59 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: 14.11 d)
- Replies: 2
- Views: 571
Re: 14.11 d)
Can someone explain how do part d, especially writing the half redox reaction for the left side? How did we know H2O was the reactant for the left but O2 the reactant for the right?
- Wed Feb 21, 2018 11:51 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: how to write a cell diagram [ENDORSED]
- Replies: 7
- Views: 2001
Re: how to write a cell diagram [ENDORSED]
Curtis Wong 2D wrote:So the order is typically Inert Metal (if applicable) | (Anode reactant) | (anode product) || (Cathode reactant) | (cathode product)| (Inert Metal if applicable).
Then how come for problem 14.11 the cathode reactant and the cathode product is switched so that Cl- is before Cl2?
- Wed Feb 21, 2018 12:42 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: how to write a cell diagram [ENDORSED]
- Replies: 7
- Views: 2001
Re: how to write a cell diagram [ENDORSED]
How come in the textbook pg 575 when the order of the galvanic cell | (Anode reactant) | (anode product) || (Cathode reactant) | (cathode product)| is flipped so that the cathode is on the left the voltage is negative, even when the electrons are still flowing from anode to cathode?
- Wed Feb 21, 2018 12:28 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: voltage
- Replies: 1
- Views: 240
voltage
What is voltage? Why do we need to multiply voltage with mols x Faraday's constant to get G?
- Wed Feb 21, 2018 10:10 am
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Electrode
- Replies: 2
- Views: 295
Electrode
What exactly is an electrode?
- Tue Feb 13, 2018 10:03 pm
- Forum: Calculating Standard Reaction Entropies (e.g. , Using Standard Molar Entropies)
- Topic: Standard Molar Entropy Question
- Replies: 3
- Views: 662
Re: Standard Molar Entropy Question
So the complexity of the molecule overrules positional disorder?
- Sun Feb 11, 2018 11:58 am
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: 11.19 and 11.83
- Replies: 3
- Views: 719
Re: 11.19 and 11.83
How do you solve for 11.19?
- Sat Feb 10, 2018 5:11 pm
- Forum: Entropy Changes Due to Changes in Volume and Temperature
- Topic: Irreversible expansion and entropy [ENDORSED]
- Replies: 1
- Views: 296
Irreversible expansion and entropy [ENDORSED]
Why is it that in a free expansion (according to page 346 in the textbook) that delta S of the surroundings is equal to 0 but delta S (system) is not. The book reasons that no work is done in free expansion so q=0, but if that is the case how can delta S (system) or delta S (total) be anything other...
- Sat Feb 10, 2018 5:01 pm
- Forum: Calculating Work of Expansion
- Topic: Reversible reaction and Detla U
- Replies: 3
- Views: 494
Reversible reaction and Detla U
Why is it that in a reversible expansion delta U is equal to zero?
- Sat Feb 10, 2018 4:44 pm
- Forum: Concepts & Calculations Using Second Law of Thermodynamics
- Topic: units conversion for entropy
- Replies: 6
- Views: 1026
Re: units conversion for entropy
I understand that the units for entropy is J/K, but can someone explain the reasoning behind it other than that it comes from the equation: delta S= q/T?
- Sat Feb 10, 2018 1:07 pm
- Forum: Entropy Changes Due to Changes in Volume and Temperature
- Topic: entropy of irreversible and reversible reactions.
- Replies: 2
- Views: 516
Re: entropy of irreversible and reversible reactions.
I don't understand why the delta S of the surroundings is zero in an irreversible process. The textbook on page 346 says that no work is done in free expansion so w=0. Can someone explain that?
- Sat Feb 10, 2018 10:49 am
- Forum: Entropy Changes Due to Changes in Volume and Temperature
- Topic: Entropy change when Temperature changes [ENDORSED]
- Replies: 6
- Views: 1385
Re: Entropy change when Temperature changes [ENDORSED]
Can someone explain how to do 9.43?
- Mon Feb 05, 2018 4:15 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: HW 9.25: Understanding Molor disorder of crystals
- Replies: 4
- Views: 1126
Re: HW 9.25: Understanding Molor disorder of crystals
you use Avogadro's number because we want to find the amount of entropy per mol, so we need to take into account all the atoms within one mol.
- Mon Feb 05, 2018 11:58 am
- Forum: Concepts & Calculations Using Second Law of Thermodynamics
- Topic: Delta U (Concept Clarification)
- Replies: 6
- Views: 667
Re: Delta U (Concept Clarification)
In what cases is delta U=0? Why is delta U zero in an isothermal expansion?
- Mon Feb 05, 2018 8:41 am
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Gibbs Free Energy
- Replies: 7
- Views: 787
Re: Gibbs Free Energy
Another way to think of entropy is the a state of relaxed disorder. Since Gibbs free energy is the amount of energy free do do work and the change in Gibbs is the energy that was needed to do work (or make a reaction happen) it is affected by the amt of heat or energy coming and leaving the system (...
- Wed Jan 31, 2018 11:45 pm
- Forum: Entropy Changes Due to Changes in Volume and Temperature
- Topic: Define Entropy
- Replies: 4
- Views: 384
Re: Define Entropy
Can someone explain why we divide q by temperature?
- Wed Jan 31, 2018 11:36 pm
- Forum: Entropy Changes Due to Changes in Volume and Temperature
- Topic: Entropy change when Temperature changes [ENDORSED]
- Replies: 6
- Views: 1385
Re: Entropy change when Temperature changes [ENDORSED]
Can someone explain how you solve number 9.5? Like what do you divide the heat with?
- Thu Jan 25, 2018 9:16 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: 8.49
- Replies: 5
- Views: 591
Re: 8.49
Since using Kelvin or Celcius will give different answers, which one should we use?
- Thu Jan 25, 2018 8:38 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: What are the types of calorimeters we learned about/ covered in class?
- Replies: 4
- Views: 465
Re: What are the types of calorimeters we learned about/ covered in class?
So what is the system and surroundings in a calorimeter with constant pressure and a bomb calorimeter?
- Thu Jan 25, 2018 6:22 pm
- Forum: Phase Changes & Related Calculations
- Topic: enthaply
- Replies: 3
- Views: 455
Re: enthaply
H is simply enthalpy whereas delta H is the change in enthalpy. Enthalpy itself is the total heat content (energy) of a system: aka the internal energy plus the product of pressure and volume. My guess as to why we use the change in enthalpy is because it is easier to calculate through experiments.
- Thu Jan 25, 2018 5:44 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Bond enthalpies vs enthalpy of rxn - conceptual [ENDORSED]
- Replies: 3
- Views: 639
Re: Bond enthalpies vs enthalpy of rxn - conceptual [ENDORSED]
However, when bonds are broken isn't energy released as well? So why is it not exothermic?
- Sat Jan 20, 2018 8:42 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Finding change in enthalpy when given bond enthalpies
- Replies: 3
- Views: 246
Re: Finding change in enthalpy when given bond enthalpies
Could you also add up all the bond enthalpies for all bonds of the products minus all the bond enthalpies for the reactants to find the reaction enthalpy?
- Sat Jan 20, 2018 12:41 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Constant Volume vs Constant Pressure
- Replies: 6
- Views: 534
Constant Volume vs Constant Pressure
I am a little confused about how systems under constant volume differ from those under constant pressure. For systems under constant volume, how is pressure changing and how do we find the work enacted on the system?
- Sat Jan 20, 2018 12:06 am
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: PV=nRT
- Replies: 4
- Views: 883
Re: PV=nRT
If the system expands or is compressed is there still a change in the net number of moles? If not, would the equation P∆V=∆nRT still hold true because the net number of moles aren't changing?
- Fri Jan 19, 2018 11:47 pm
- Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
- Topic: Thermochemical equation
- Replies: 5
- Views: 764
Re: Thermochemical equation
Can someone explain why the thermochemical equation on pg 288 example 8.7 is that change in enthaply= q x (2 mol)/n? Why would you divide the stoichiometric coefficient of original equation by the number of mols?
- Fri Jan 19, 2018 10:00 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Change in internal energy
- Replies: 3
- Views: 1495
Re: Change in internal energy
Is there a change in work in the form of volume or pressure? isn't the reaction already contains a mol of OF2? How do you calculate the change in work if so.
- Fri Jan 19, 2018 10:24 am
- Forum: Phase Changes & Related Calculations
- Topic: Chapter 8 Homework Question 8.37
- Replies: 2
- Views: 1238
Re: Chapter 8 Homework Question 8.37
When it asks for the enthalpy of vaporization is it always have to be in mols? or can it be in KJ/g as well.
- Thu Jan 18, 2018 6:30 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Problem 7.27 Need some help
- Replies: 5
- Views: 2078
Re: Problem 7.27 Need some help
what does it mean for heat to be released at a constant volume? Can someone explain why it corresponds to a new heat capacity (C)
- Sat Jan 13, 2018 11:25 am
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Calorimeter
- Replies: 1
- Views: 268
Calorimeter
When the textbook refers to the internal energy in example 8.4 on pg 271, is it refering to the heating device or the calorimeter? If it is the calorimeter, wouldn't the change in the internal energy be positive?
- Fri Jan 12, 2018 9:15 pm
- Forum: Calculating Work of Expansion
- Topic: Calculating required heat
- Replies: 5
- Views: 7369
Re: Calculating required heat
I don't really get why you need to add the heat of the kettle and the heat of the water together. I thought it was just asking for the heat supplied to the kettle to heat it up to 100 degrees Celsius.
- Thu Jan 11, 2018 11:41 am
- Forum: Phase Changes & Related Calculations
- Topic: Open, Closed, or Isolated Systems
- Replies: 6
- Views: 10501
Re: Open, Closed, or Isolated Systems
Can someone explain exercise 8.1 part e? Why would mercury in a thermometer be a closed system rather than isolated?
- Tue Jan 09, 2018 10:50 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Office Hours [ENDORSED]
- Replies: 1
- Views: 233
Office Hours [ENDORSED]
Lavelle's office hours conflict with my LS30B math class. Is there any other way I can meet up with him to ask questions or is the only other option the TA office hours?
- Thu Dec 07, 2017 10:09 pm
- Forum: Bronsted Acids & Bases
- Topic: 12.115
- Replies: 1
- Views: 303
12.115
Acetic acid is used as a solvent for some reactions between acids and bases. (a) Nitrous acid and carbonic acids are both weak acids in water. Will either of them act as a strong acid in acetic acid? Explain your answer. (b) Will ammonia act as a strong or weak base in acetic acid? Explain your answ...
- Wed Dec 06, 2017 11:27 pm
- Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
- Topic: 11.59
- Replies: 4
- Views: 3748
Re: 11.59
Why does this answer differ from the table 12.1 acidity constants? Shouldn't the Ka of HClO2 be the same?
- Tue Dec 05, 2017 9:28 pm
- Forum: Conjugate Acids & Bases
- Topic: HW: 12.17
- Replies: 4
- Views: 862
Re: HW: 12.17
Can someone explain why BaO is basic and As2O3 and Bi2O3 amphoteric?
- Tue Dec 05, 2017 8:14 pm
- Forum: Photoelectric Effect
- Topic: Midterm question [ENDORSED]
- Replies: 6
- Views: 758
Re: Midterm question [ENDORSED]
Wouldn't increasing the frequency of a light even if it originally did not have the energy to emit an electron eventually lead to an electron being emitted from the metal, because if E=hv and v increases, wouldn't the energy of the photon increase until it surpasses the work function?
- Sat Dec 02, 2017 10:44 am
- Forum: Properties & Structures of Inorganic & Organic Acids
- Topic: Strong acid vs weak acid [ENDORSED]
- Replies: 7
- Views: 1019
Re: Strong acid vs weak acid [ENDORSED]
What makes a strong acid completely ionize or disassociate as opposed to a weak one?
- Mon Nov 27, 2017 10:16 am
- Forum: Naming
- Topic: Oxidation Number [ENDORSED]
- Replies: 1
- Views: 347
Oxidation Number [ENDORSED]
What is the oxidation number?
- Sat Nov 25, 2017 8:03 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: 11.11
- Replies: 3
- Views: 692
11.11
A 0.10-mol sample of pure ozone, O3, is placed in a sealed 1.0-L container and the reaction 2 O3(g)∆3 O2(g) is allowed to reach equilibrium. A 0.50-mol sample of pure ozone is placed in a second 1.0-L container at the same temperature and allowed to reach equilibrium. Without doing any calculations,...
- Sat Nov 25, 2017 7:59 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Equilibrium
- Replies: 2
- Views: 246
Equilibrium
Why in equilibrium the reaction of reactants turning into products and vice versa is still happening? Why doesn't the reactants completely react with each (so their concentration reaches zero) to form the product?
- Sat Nov 25, 2017 2:27 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Equilibrium and Disassociation of a Diatomic Molecule (11.7)
- Replies: 8
- Views: 3899
Re: Equilibrium and Disassociation of a Diatomic Molecule (11.7)
can someone explain part c in detail, please?
- Tue Nov 21, 2017 10:50 am
- Forum: Hybridization
- Topic: 4.95
- Replies: 3
- Views: 344
4.95
Can someone explain what does the numbers in front of the hybrid orbitals mean? Like 2(sp2) or 1S. Is it the number of hybrid orbitals there are or is it related to the row on the periodic table?
- Mon Nov 20, 2017 7:52 pm
- Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
- Topic: HW 4.75
- Replies: 2
- Views: 344
HW 4.75
An organic compound distilled from wood was found to have a molar mass of 32.04 g·mol"1 and the following composition by mass: 37.5% C, 12.6% H, and 49.9% O. (a)Write the Lewis structure of the compound and determine the bond angles about the carbon and oxygen atoms. (b) Give the hybridization ...
- Wed Nov 15, 2017 5:42 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Midterm re-grade?
- Replies: 2
- Views: 314
Midterm re-grade?
Is there any way to re-grade the midterm, because I checked the solutions for midterm and for Q8B I feel like I should get partial credit for saying that the compound was a radical even if Lewis structure might be slightly off. Also how many points should be taken off with we make one mistake, like ...
- Tue Nov 14, 2017 10:37 pm
- Forum: Hybridization
- Topic: Diapole
- Replies: 4
- Views: 715
Diapole
Can someone explain what dipole is?
- Tue Nov 14, 2017 10:35 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Electron Density [ENDORSED]
- Replies: 4
- Views: 574
Re: Electron Density [ENDORSED]
Why do we not count the lone pairs on other atoms bonded to the central atom as regions of electron density?
- Fri Nov 10, 2017 4:59 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Electron Density [ENDORSED]
- Replies: 4
- Views: 574
Electron Density [ENDORSED]
Do we only count the lone pairs on the central atom as regions of electron density?
- Mon Nov 06, 2017 9:04 pm
- Forum: Lewis Structures
- Topic: Radicals
- Replies: 4
- Views: 798
Re: Radicals
Can someone explain what a radical is?
- Sat Nov 04, 2017 9:45 pm
- Forum: Lewis Structures
- Topic: Lewis Structure
- Replies: 4
- Views: 2923
Re: Lewis Structure
Why is the element with the lowest ionizing energy is in the center?
- Sat Nov 04, 2017 9:32 pm
- Forum: Ionic & Covalent Bonds
- Topic: Giving the chemical formula of compounds.
- Replies: 3
- Views: 1219
Re: Giving the chemical formula of compounds.
Can someone explain specifically how you get the chemical formula for part (c) aluminum hydride and (e)bismuth(III)fluoride?
- Sat Nov 04, 2017 12:08 am
- Forum: Trends in The Periodic Table
- Topic: why carbon has a higher electron affinity than nitrogen.
- Replies: 5
- Views: 7581
Re: why carbon has a higher electron affinity than nitrogen.
It is because the orbitals of Carbon is only 1/3 filled whereas Nitrogen has 3 out of the 6 electrons which is more balanced, thus it does not require another electron as much.
- Sat Nov 04, 2017 12:04 am
- Forum: Electronegativity
- Topic: Difference between electron affinity and electronegativity
- Replies: 3
- Views: 2132
Re: Difference between electron affinity and electronegativity
Why is energy released when electrons is added to a gas phase atom?
- Sat Oct 28, 2017 11:56 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Valence-shell configuration [ENDORSED]
- Replies: 3
- Views: 2701
Re: Valence-shell configuration [ENDORSED]
Can someone explain to me why the answer to part (c) is (n-1)d^5ns^2 rather than (n-1)d^3ns^2?
- Fri Oct 27, 2017 1:31 pm
- Forum: Formal Charge and Oxidation Numbers
- Topic: Quick Question about SO4
- Replies: 8
- Views: 1290
Re: Quick Question about SO4
If both structures have the same net charge then why is one "better" than the other?
- Fri Oct 27, 2017 1:26 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Homework 2.37 [ENDORSED]
- Replies: 7
- Views: 5319
Re: Homework 2.37 [ENDORSED]
What is the effective nuclear charge?
- Fri Oct 27, 2017 1:25 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Homework 2.37 [ENDORSED]
- Replies: 7
- Views: 5319
Re: Homework 2.37 [ENDORSED]
Can someone explain how electron shielding works?
- Fri Oct 27, 2017 1:21 pm
- Forum: Ionic & Covalent Bonds
- Topic: Cations and Anions [ENDORSED]
- Replies: 12
- Views: 2097
Re: Cations and Anions [ENDORSED]
How can an atom have the same properties when they lose an electron if different elements are separated with just a one-electron one proton difference.
- Fri Oct 13, 2017 7:31 pm
- Forum: Properties of Light
- Topic: 1.3 homework [ENDORSED]
- Replies: 11
- Views: 1293
Re: 1.3 homework [ENDORSED]
How does the amplitude of the waves correspond with the lower frequency?
- Thu Oct 12, 2017 9:40 pm
- Forum: Photoelectric Effect
- Topic: Photoelectric effect post-quiz 17-19 [ENDORSED]
- Replies: 7
- Views: 5382
Re: Photoelectric effect post-quiz 17-19 [ENDORSED]
How did you get 2.5x10^-19 as the work energy?
- Thu Oct 05, 2017 4:04 pm
- Forum: Accuracy, Precision, Mole, Other Definitions
- Topic: E.27 [ENDORSED]
- Replies: 2
- Views: 436
E.27 [ENDORSED]
Can someone explain part a) Calculate the mass, in grams, of one water molecule?
- Thu Oct 05, 2017 3:55 pm
- Forum: Accuracy, Precision, Mole, Other Definitions
- Topic: E.27
- Replies: 2
- Views: 544
E.27
Can someone explain part a) Calculate the mass, in grams, of one water molecule?
- Mon Oct 02, 2017 10:16 pm
- Forum: Molarity, Solutions, Dilutions
- Topic: G17
- Replies: 2
- Views: 6418
Re: G17
For part b) First, find the number of moles for just K2S because that is the only molecule that has sulfide: .500 grams/(39.1(2) +32.06) = .00453 moles Then multiply .00453 by ratio of moles of sulfide over K2S, which is 1/1 so you get. Then plug the numbers into the formula: moles/volume= molarity;...