Search found 72 matches

by Baoying Li 1B
Thu Jan 23, 2020 10:59 pm
Forum: Phase Changes & Related Calculations
Topic: Heat Capacity
Replies: 2
Views: 11

Heat Capacity

What are the types of heat capacity?
by Baoying Li 1B
Thu Jan 23, 2020 10:54 pm
Forum: Phase Changes & Related Calculations
Topic: Constant pressure and constant volume
Replies: 1
Views: 24

Constant pressure and constant volume

What is the difference between constant pressure and constant volume? How would the heat, work, and internal energy respond to these two states?
by Baoying Li 1B
Thu Jan 23, 2020 10:49 pm
Forum: Phase Changes & Related Calculations
Topic: Celsius and Kelvin
Replies: 3
Views: 9

Celsius and Kelvin

When you can replace the Celsius with Kelvin without doing the conversion?
by Baoying Li 1B
Thu Jan 23, 2020 10:48 pm
Forum: Phase Changes & Related Calculations
Topic: symbol of Heat
Replies: 3
Views: 15

symbol of Heat

What do these symbols represent specifically? H, delta H, Delta H naught, qp, q.
by Baoying Li 1B
Thu Jan 23, 2020 10:42 pm
Forum: Phase Changes & Related Calculations
Topic: Steam vs. Boiling Water
Replies: 9
Views: 28

Steam vs. Boiling Water

Can someone explain again why steam at 100 Celsius causes a worse burn than boiling water at 100 Celsius? I know Dr. Lavelle has talked about this during the lecture. I just want to make sure that if I get it right.
by Baoying Li 1B
Sun Jan 19, 2020 8:52 pm
Forum: General Science Questions
Topic: test 1
Replies: 8
Views: 41

Re: test 1

Yes. The test will be taking during the discussion. If your discussion is on Tuesday, then you will have a test on that day. It covers outline 1 and outline 2’s materials(chemical equilibrium & acid and base equilibrium). Good luck!
by Baoying Li 1B
Sun Jan 19, 2020 7:08 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: ice boc
Replies: 7
Views: 17

Re: ice boc

Using Ice box can help us organize our thoughts and avoid to make mistakes. I suggest to use it just in case or it may help you get some partial credit.
by Baoying Li 1B
Sun Jan 19, 2020 7:06 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: When do we use the equilibrium sign?
Replies: 7
Views: 17

When do we use the equilibrium sign?

When do we use the equilibrium sign (the double arrows) in the chemical reaction? Based on my knowledge, if the reactants completely dissolve in the reaction, we can use it. However, I have seen the chemical reaction of weak bases and weak acids also use the equilibrium sign. But couldn’t they disso...
by Baoying Li 1B
Sun Jan 19, 2020 6:58 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: question 6B.7
Replies: 4
Views: 11

Re: question 6B.7

Since pH=-log[H3O+}, the concentration of H3O+ would be 10 to the -pH.
by Baoying Li 1B
Wed Jan 15, 2020 10:32 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: 6C#9
Replies: 2
Views: 9

6C#9

Can someone explain the process of solving this problem?
by Baoying Li 1B
Thu Jan 09, 2020 8:38 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: 5J.13
Replies: 2
Views: 15

Re: 5J.13

You can compare the equilibrium constants of this reaction under different temperatures to see whether the reaction is exothermic or endothermic. If the equilibrium constant in the lower temperature is higher than the equilibrium constant in the higher temperature, the reaction is exothermic. The op...
by Baoying Li 1B
Thu Jan 09, 2020 8:33 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Post-Assessment-Part 3
Replies: 2
Views: 32

Post-Assessment-Part 3

For problem#20 in Post-Assessment-Part 3, what are the steps of solving this problem? What is the answer? What does the "c" mean in the "c+2x" which represents the equilibrium concentration of SO3?
by Baoying Li 1B
Thu Jan 09, 2020 8:25 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Kc and Kp
Replies: 4
Views: 17

Re: Kc and Kp

You are right with both Kc and Kp.
Kc is the equilibrium constant of the concentration of the aqueous solution.
Kp is the equilibrium constant of the partial pressure of the gas.
by Baoying Li 1B
Thu Jan 09, 2020 8:23 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Calculating K
Replies: 6
Views: 29

Re: Calculating K

I think it's one over the concentration of the substance as a reactant(neither a solid or pure liquid). This shows the equilibrium constant of the forward reaction whereas the reverse reaction will only be the concentration of the substance.
by Baoying Li 1B
Thu Jan 09, 2020 8:18 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: 5G.7
Replies: 5
Views: 32

Re: 5G.7

Yes. Use partial pressure to find the equilibrium constant, Kp for the gas. Use concentration to find the equilibrium constant, Kc for aqueous solution.
by Baoying Li 1B
Thu Jan 09, 2020 8:15 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Volume and Equilibrium
Replies: 3
Views: 13

Re: Volume and Equilibrium

I believe that changing the volume will not affect the equilibrium constant because the direction of the reaction will change respectively in order to minimize this effect(Le Chatelier's Principle). If volume decreases and more reactants on the left side, the reaction proceeds to the right to produc...
by Baoying Li 1B
Sat Dec 07, 2019 9:12 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Lone pairs location
Replies: 3
Views: 32

Lone pairs location

How do you where the lone pairs lie in a trigonal pyramidal shape and in a seesaw shape?
by Baoying Li 1B
Sat Dec 07, 2019 9:03 pm
Forum: Amphoteric Compounds
Topic: As2O and Bi2O3
Replies: 4
Views: 34

As2O and Bi2O3

Why are both As2O and Bi2O3 amphoteric compounds?
by Baoying Li 1B
Sat Dec 07, 2019 8:50 pm
Forum: Biological Examples
Topic: Vitamin B12
Replies: 2
Views: 48

Re: Vitamin B12

There's a problem with Vitamin B12 in one of UA's worksheets. You can search "Karen" and click the title "Karen Sun workshop." There's a worksheet called "Worksheet F19--Coordination Compounds." I think that's very helpful. What is the structure of Vitamin B12? I know t...
by Baoying Li 1B
Sat Dec 07, 2019 8:37 pm
Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
Topic: Ka. Kb, Kw
Replies: 4
Views: 35

Ka. Kb, Kw

What is the difference between Ka, Kb, and Kw?
Also, what is the difference between Ka1 and Ka2?
Do we need to calculate Ka and Kb in the final?
by Baoying Li 1B
Sat Dec 07, 2019 8:33 pm
Forum: Identifying Acidic & Basic Salts
Topic: Hw Problem 6D.11
Replies: 4
Views: 53

Re: Hw Problem 6D.11

Memorize all the strong acids and weak strong. Others will be weak acids and weak bases.
by Baoying Li 1B
Sat Dec 07, 2019 8:31 pm
Forum: Amphoteric Compounds
Topic: Methods to identify whether it's Amphoteric, basic or acidic
Replies: 1
Views: 32

Methods to identify whether it's Amphoteric, basic or acidic

How do you know whether a compound is amphoteric, basic, or acidic? Are there any methods?
by Baoying Li 1B
Sat Dec 07, 2019 8:23 pm
Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
Topic: Bond order
Replies: 2
Views: 31

Re: Bond order

Bond order= #of bonds of an atom divide by the # of atom it is connected with. single bond=1 double bond=2 It just means the average bond number.
The bond order of Cl2 is 1.
by Baoying Li 1B
Sun Dec 01, 2019 11:07 pm
Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
Topic: Class wed 11/27
Replies: 7
Views: 53

Re: Class wed 11/27

1. Reaction btw acid and base--Neutralization
2. Writing [H3O+] AND [OH-] as logarithms
3. Relative acidity (Binary, oxoacid, carboxylic)
Hope this helps!
by Baoying Li 1B
Sun Dec 01, 2019 9:48 pm
Forum: Lewis Acids & Bases
Topic: Relative acidity
Replies: 4
Views: 19

Relative acidity

What are the rules to distinguish which is a stronger acid or a weaker acid?
by Baoying Li 1B
Sun Dec 01, 2019 2:15 am
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Oxidation number
Replies: 3
Views: 26

Oxidation number

How can you determine the oxidation number of the transitional metal in a complex?
by Baoying Li 1B
Sun Dec 01, 2019 2:10 am
Forum: Lewis Acids & Bases
Topic: Conjugate acid and conjugate base
Replies: 2
Views: 19

Conjugate acid and conjugate base

How can we distinguish conjugate acid and conjugate base? Is there any shortcut or a clear/systematic way to identify them?
by Baoying Li 1B
Sun Dec 01, 2019 2:02 am
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Coordination Number
Replies: 6
Views: 37

Coordination Number

How do you know the coordination number of a complex? Like Ba[FeBr4]2
by Baoying Li 1B
Thu Nov 21, 2019 9:18 pm
Forum: Dipole Moments
Topic: boiling point example
Replies: 3
Views: 40

Re: boiling point example

I think that the molar mass only works for London dispersion forces. The dominant intermolecular force of KCl and KI is ion-ion which depends on the polarity. The higher the difference of electronegativity between elements, the higher the boiling point. Cl has a higher electronegativity than I. So K...
by Baoying Li 1B
Thu Nov 21, 2019 9:10 pm
Forum: Sigma & Pi Bonds
Topic: How to Find Sigma Bonds and Pi Bonds
Replies: 15
Views: 103

Re: How to Find Sigma Bonds and Pi Bonds

First, draw the Lewis structure. Observe the bond between atoms.
Use these rules can help you find Sigma bonds and Pi bonds:
Single bond-one sigma bond
Double bond-one sigma bond and one pi bond
Triple bond-one sigma bond and two pi bonds
by Baoying Li 1B
Thu Nov 21, 2019 9:08 pm
Forum: Sigma & Pi Bonds
Topic: HW 2F.3.
Replies: 2
Views: 26

Re: HW 2F.3.

2F.3. How many sigma bonds and how many pi bonds are there in a) H2S? b) SO2? How do you find how many sigma and pi bonds there are in a molecule? So, the first thing is to draw a Lewis structure. a) Both H-S bonds are single bonds. A single bond contains a sigma bond. So in total, there are two sig...
by Baoying Li 1B
Thu Nov 21, 2019 9:00 pm
Forum: Bond Lengths & Energies
Topic: Boiling Point
Replies: 7
Views: 74

Re: Boiling Point

London dispersion forces depend on the mass of a molecular. The greater the mass, the greater the forces. Boiling point increases due to the increasing molar masses, increasing surface tension, increasing intermolecular forces. Also, larger polarity results in greater intermolecular attractive force...
by Baoying Li 1B
Sun Nov 17, 2019 12:29 pm
Forum: Lewis Structures
Topic: Carbon Monoxide
Replies: 4
Views: 29

Re: Carbon Monoxide

Because the number of valence electron of C and O is 10, 5pairs. If you draw a double bond between C and O, you will need 12 electrons to finish the octet. Also, you can check the formal charge of each element. The lower the formal charge, the more stable the molecule is.
by Baoying Li 1B
Sun Nov 17, 2019 12:03 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Angles less than 109.5 degrees
Replies: 5
Views: 29

Angles less than 109.5 degrees

Hi guys. I have a question that why is the angle of trigonal pyramidal less than 109.5 degrees but not less than 120 degrees since the angle of trigonal planar is 120 degrees. Also, same as the angular shape, why is the angle not less than 180 degrees but less than 120 degrees?
by Baoying Li 1B
Thu Nov 14, 2019 2:57 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: 2E.11
Replies: 4
Views: 21

Re: 2E.11

Because when you draw the Lewis Structure, there are two lone pairs on top of Iodine. These two lone pairs make the original structure(tetrahedral) bend to a square planar structure. The arrangement is octahedral. It doesn't mean that the structure is the same as well.
by Baoying Li 1B
Thu Nov 14, 2019 2:48 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Test 2
Replies: 2
Views: 18

Test 2

What do we need to know in order to get well-prepared for Test 2?
by Baoying Li 1B
Thu Nov 14, 2019 2:47 pm
Forum: Hybridization
Topic: Relationship btw arrangement and hybrid orbitals
Replies: 2
Views: 37

Relationship btw arrangement and hybrid orbitals

Is there a relationship between the arrangement of an atom and the hybrid orbitals used by the atom?
by Baoying Li 1B
Thu Nov 14, 2019 2:38 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Arrangement and Shape
Replies: 2
Views: 28

Arrangement and Shape

What is the difference between the arrangement and shape of a molecular compound? When do lone pairs matter?
by Baoying Li 1B
Tue Nov 05, 2019 7:54 pm
Forum: Ionic & Covalent Bonds
Topic: Textbook question 2.25
Replies: 2
Views: 31

Re: Textbook question 2.25

Which bond is longer: (a) the CN bond in HCN or in H3CNH2? (b) The NF bond in NF3 or the PF bond in PF3? For part A, I got that the bond in H3CNH2 is longer, is this the correct answer? For part B, I got that the NF bond in NF3 and the PF bond in PF3 were the same length--is this correct? You got th...
by Baoying Li 1B
Tue Nov 05, 2019 7:49 pm
Forum: Properties of Light
Topic: Lecture Tomorrow
Replies: 1
Views: 31

Re: Lecture Tomorrow

There's no lecture tmr. Professor Lavelle has sent an email to confirm this. Good luck on your Midterm!
by Baoying Li 1B
Tue Nov 05, 2019 7:42 pm
Forum: Properties of Light
Topic: Rydberg Equation
Replies: 5
Views: 80

Re: Rydberg Equation

I think we need to know that the energy level starts from n=1 for Lyman series(UV region) and it starts from n=2 for Balmer series(visible region, 700nm-400nm).
by Baoying Li 1B
Tue Nov 05, 2019 7:36 pm
Forum: Student Social/Study Group
Topic: Post All Chemistry Jokes Here
Replies: 7752
Views: 1070994

Re: Post All Chemistry Jokes Here

Once I told Chemistry a joke, there's no reaction.
by Baoying Li 1B
Tue Nov 05, 2019 7:34 pm
Forum: Properties of Electrons
Topic: Mass of an electron
Replies: 9
Views: 64

Re: Mass of an electron

No, you don't have to remember the mass of an electron. It will be on the reference sheet which will be provided to you during the midterm as test 1.
by Baoying Li 1B
Tue Nov 05, 2019 7:30 pm
Forum: Octet Exceptions
Topic: Did I summarize the octet rule exception correctly?
Replies: 1
Views: 26

Re: Did I summarize the octet rule exception correctly?

Yes, I think your summary is pretty good. Just be aware that the formal charge is not always equal to zero, but the more close to zero, the more stable the structure is. Elements like P, As, Cl, As and etc. usually break the octet rule because of their odd valence electrons. Lastly, make sure the to...
by Baoying Li 1B
Tue Nov 05, 2019 7:19 pm
Forum: Polarisability of Anions, The Polarizing Power of Cations
Topic: Oxidation state for Midterm
Replies: 1
Views: 25

Oxidation state for Midterm

Hey, do we need to know about the oxidation state for the midterm?
by Baoying Li 1B
Thu Oct 31, 2019 9:52 pm
Forum: Electronegativity
Topic: 2D.1
Replies: 4
Views: 40

Re: 2D.1

Electronegativity increases as you go down to a group and decreases as you go across a period.
by Baoying Li 1B
Thu Oct 31, 2019 9:14 pm
Forum: Octet Exceptions
Topic: 2C.9
Replies: 4
Views: 34

Re: 2C.9

You can count the valences of electron of the Lewis structure and check that if it's equal to the number of valence of electrons you have calculated. Since there are 42 valences of electron in XeOF2, Xe has one lone pair.
by Baoying Li 1B
Thu Oct 31, 2019 4:35 pm
Forum: Lewis Structures
Topic: Hw 2B 5b
Replies: 1
Views: 22

Hw 2B 5b

For this problem, I got 21 for the number of valence electrons of NHF2. But the answer shows only 20 valence electrons. I wonder if I calculated the number of valence electrons wrong?
by Baoying Li 1B
Thu Oct 31, 2019 3:48 pm
Forum: Octet Exceptions
Topic: En
Replies: 3
Views: 28

En

What does En represent? According to the notes, if En is greater than 2, it's an ionic bond; if En is less than 1.5, it's a covalent bond. What if the En is in between 2 and 1.5? What would it be?
by Baoying Li 1B
Thu Oct 31, 2019 3:41 pm
Forum: Formal Charge and Oxidation Numbers
Topic: Formal Charge Calculation
Replies: 4
Views: 47

Formal Charge Calculation

Hey guys, can someone explain the process of assigning formal charges in detail? What is it mean to count the bonding? Why is the resonance the most stable when Fc equals to 0?
by Baoying Li 1B
Thu Oct 24, 2019 7:09 pm
Forum: Ionic & Covalent Bonds
Topic: HW 2A#5 part a
Replies: 2
Views: 36

HW 2A#5 part a

I wonder why the answer is 3d^10, not 3d^8 4s^2? Shouldn't we remove the electrons of the outermost energy level first? Or it depends on how we write the electronic configuration?
by Baoying Li 1B
Thu Oct 24, 2019 7:01 pm
Forum: Lewis Structures
Topic: Where to start putting dots for electrons
Replies: 10
Views: 73

Re: Where to start putting dots for electrons

There's actually no rules of putting the dots for electrons. As long as you put the right number of valence electons, you will be fine. Make sure that pair up two electrons first and the put the next eletron.
by Baoying Li 1B
Tue Oct 22, 2019 10:15 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: 4s and 3d
Replies: 5
Views: 41

4s and 3d

Hi, can anyone explain why does 4s come before 3d since the energy level n=3 is lower than n=4? I know Professor Lavelle has explained this, but I am still confused.
by Baoying Li 1B
Tue Oct 22, 2019 10:05 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Atomic radius vs. Ionic radius
Replies: 5
Views: 36

Re: Atomic radius vs. Ionic radius

Both atomic radius and ionic radius show the same trend: increase down a group and decrease down a period. However, the atomic radius is always smaller than the ionic radius. Ex. Na+=1.02 Angstroms Na=1.54 Angstroms
by Baoying Li 1B
Tue Oct 22, 2019 9:48 pm
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: KeV
Replies: 2
Views: 30

Re: KeV

In the unit "keV", "k" stands for kilo(10^3) and "eV" stands for electron volt, a unit of energy equal to the energy acquired by an electron in being accelerated through a potential difference of 1 volt. Therefore, "keV" is kilo-electron volt. For problem 1B5,...
by Baoying Li 1B
Thu Oct 17, 2019 11:39 am
Forum: Photoelectric Effect
Topic: Calculating the number of photons [ENDORSED]
Replies: 2
Views: 33

Re: Calculating the number of photons [ENDORSED]

First, you need to find the velocity of a proton by using the formula v=c/wavelength. Then you can find the amount of energy per proton by using the formula E=hv. You use the total energy in the 2s divide by the energy of one proton. You will get the total amount of protons in this energy. In order ...
by Baoying Li 1B
Tue Oct 15, 2019 10:56 am
Forum: Properties of Light
Topic: Atomic Spectra Post-Module Assessment
Replies: 1
Views: 32

Atomic Spectra Post-Module Assessment

Hey guys. What are the answers to #40, 43.44? And can you show the process of how to solve one of them?
by Baoying Li 1B
Mon Oct 14, 2019 10:29 pm
Forum: DeBroglie Equation
Topic: Three Fundamental Equations
Replies: 3
Views: 35

Three Fundamental Equations

When you are solving a problem, how do you know which fundamental equation you are using? What are some keywords in the problems that may help? For example, E =pv, hv, hc/wavelength.
by Baoying Li 1B
Mon Oct 14, 2019 10:16 pm
Forum: Photoelectric Effect
Topic: 29B and 30C
Replies: 1
Views: 32

Re: 29B and 30C

A. What is the kinetic energy of the ejected electron? 1.99*10^-19J Your answer is correct. 29. B. How much energy is required to remove an electron from one sodium atom? The energy that is required to remove an electron is the work funtion, which is 150.6 kJ.mol^-1. You need to find the energy per ...
by Baoying Li 1B
Mon Oct 14, 2019 10:04 pm
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: Unit keV
Replies: 4
Views: 42

Re: Unit keV

In the unit "keV", "k" stands for kilo(10^3) and "eV" stands for electron volt, a unit of energy equal to the energy acquired by an electron in being accelerated through a potential difference of 1 volt. Therefore, "keV" is kilo-electron volt. For problem 1B5,...
by Baoying Li 1B
Wed Oct 09, 2019 8:46 pm
Forum: Photoelectric Effect
Topic: Topic 1A.3
Replies: 2
Views: 34

Re: Topic 1A.3

Since E=hv, the energy per photon is proportional to frequency. As a result, if frequency decreases, the wavelength widens. So the amplitidue of the wave shortens, which corresponds to the extent of the energy--decreases as well, making C the correct answer.
by Baoying Li 1B
Wed Oct 09, 2019 8:34 pm
Forum: Photoelectric Effect
Topic: Energy of Photon = Work Function
Replies: 4
Views: 56

Re: Energy of Photon = Work Function

If a photon has an energy equals the work function, the photon energy can be transferred to the electron and the electron will have enough energy to escape from the metal. The kinetic energy will be zero.
by Baoying Li 1B
Wed Oct 09, 2019 8:32 pm
Forum: Significant Figures
Topic: %Mass Composition
Replies: 12
Views: 129

Re: %Mass Composition

It depends on the number with the lowest significant figures in this case(division). It probably will be 4 or 5 significant figures.
by Baoying Li 1B
Wed Oct 09, 2019 8:23 pm
Forum: Properties of Light
Topic: HW 1B.5
Replies: 1
Views: 24

HW 1B.5

Hey guys. How do you convert the unit ev to J*e/v? And I want to check the final answer as well.
by Baoying Li 1B
Wed Oct 09, 2019 8:19 pm
Forum: Properties of Light
Topic: HW Question #1A.15
Replies: 6
Views: 48

Re: HW Question #1A.15

The "ultraviolet region" is the same as saying the Lyman series, which starts from n1=1. Just remember this. And I think the final energy level is the inside energy level whereas the initial energy level is the outside energy level. Image the energy level as the target sign. The light shin...
by Baoying Li 1B
Wed Oct 09, 2019 8:08 pm
Forum: Properties of Light
Topic: Constants in the Quantum World
Replies: 6
Views: 51

Constants in the Quantum World

Hey, can anyone list all the constants of the formulas of quantum for future reference? Like the speed of light is c=3.00*10^8 m/s, what else? Do we need to remember all of them? I believe it will save most of us lots of time. Thank you.
by Baoying Li 1B
Thu Oct 03, 2019 3:46 pm
Forum: SI Units, Unit Conversions
Topic: Question about Showing Work
Replies: 22
Views: 209

Re: Question about Showing Work

I would suggest you definitely to show all your work just in case to get partial credit if some parts of your solution are incorrect. Also, it depends on how much time you have left for that question. You can always go back and add some details.
by Baoying Li 1B
Mon Sep 30, 2019 10:18 pm
Forum: Accuracy, Precision, Mole, Other Definitions
Topic: Avogadro's Number
Replies: 4
Views: 59

Avogadro's Number

Hey, there. Just a minor question that is kinda bothering me. According to the textbook, it uses the Avogadro's number as 6.0221*10^23. However, during the lecture, Professor Lavelle uses 6.022*10^23. So, which one are we using?
by Baoying Li 1B
Mon Sep 30, 2019 9:22 pm
Forum: Limiting Reactant Calculations
Topic: Methods of identifying Limiting Reactants
Replies: 5
Views: 82

Methods of identifying Limiting Reactants

Hey guys, is there a way to recognize the limiting reactants quickly instead of go through many calculations? What are your guys' strategies of finding Limiting Reactants? Or how can we check our answers? How does the Mole to Mole ratio work?
by Baoying Li 1B
Mon Sep 30, 2019 9:13 pm
Forum: SI Units, Unit Conversions
Topic: mol, g.mol and g.mol-1
Replies: 12
Views: 152

mol, g.mol and g.mol-1

Hello! I am confused about the units mol, g.mol and g.mol-1. They appear often in the textbook. Are they interchangeable? What's the difference?
by Baoying Li 1B
Mon Sep 30, 2019 9:02 pm
Forum: Empirical & Molecular Formulas
Topic: Homework Problem F.17
Replies: 2
Views: 42

Re: Homework Problem F.17

Yes, your answer is right. The Empirical Formula is OsC4O4. By dividing the molar mass of the OsC4O4(302.27g.mol) from the 907g.mol(given), 3 is the ratio. Therefore, multiply the 3 with the Empirical Formula. You will get Os3C12O12 as the Molecular Formula. Always check the ratio!
by Baoying Li 1B
Mon Sep 30, 2019 8:50 pm
Forum: Molarity, Solutions, Dilutions
Topic: Homework Problem E. 19
Replies: 2
Views: 60

Homework Problem E. 19

Hey guys! I have questions regarding part b), part c) and part d) of the Homework Problem E.19. b) I don't really understand this question. What does it mean that the volume occupied by the D20 molecule is the same as that occupied by an H20 molecule? How is that relevant to the density? c)How to ca...

Go to advanced search