## Search found 82 matches

Sat Jan 16, 2021 5:49 pm
Forum: Student Social/Study Group
Topic: Best Workshops
Replies: 6
Views: 28

### Re: Best Workshops

I believe that all the UAs workshops are helpful. They all have a good understanding of the materials and always try their best to help the students. Personally, I liked going to Justin's and Kate's workshop because they do a really good job on teaching the material and answering any questions stude...
Wed Jan 13, 2021 8:48 pm
Forum: Student Social/Study Group
Topic: Study Habits
Replies: 88
Views: 206

### Re: Study Habits

From chem 14a I learned not to stress over chemistry too much. My advice would be to attend one or two UA sessions per week, do textbook problems, review lecture notes, and make a study guide using the learning outcomes
Wed Jan 13, 2021 8:44 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: 5J.5 part d
Replies: 6
Views: 21

### Re: 5J.5 part d

The coefficient on HD is 2 so there are two moles on the reactant side. The coefficient on H2 gas and D2 gas is 1 so there are 2 moles of gases on the product side. I think you are probably miscalculating the number of the moles on each side. I don't see 3 moles of reactants for d. Isn't the H2 on ...
Mon Jan 11, 2021 9:18 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: 5J.5 part d
Replies: 6
Views: 21

### Re: 5J.5 part d

The coefficient on HD is 2 so there are two moles on the reactant side. The coefficient on H2 gas and D2 gas is 1 so there are 2 moles of gases on the product side.
I think you are probably miscalculating the number of the moles on each side. I don't see 3 moles of reactants for d.
Mon Jan 11, 2021 8:17 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Getting two positive x values when using quadratic
Replies: 29
Views: 113

### Re: Getting two positive x values when using quadratic

If you want to practice ICE tables with two positive x values, topic 5I has textbook problems that pertains to these types of problems. Usually, one of the positive value, when plugged in, would cause you to have a negative new equilibrium concentration.Therefore, you will be able to eliminate that ...
Mon Jan 11, 2021 8:12 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Simplifying Expressions: K<10^?
Replies: 6
Views: 42

### Re: Simplifying Expressions: K<10^?

I would say use 10^-3 because this is the value used in the textbook too. The video are few years old and the chemistry community is constantly evolving with new ways to write/identify things. So, I would trust his lecture more since they are newer than the audio visual videos.
Sat Jan 09, 2021 7:36 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Calculating concentration using the quadratic formula
Replies: 6
Views: 28

### Calculating concentration using the quadratic formula

I understand how to use the ice/rice table to calculate the value of x to find the concentrations. Hypothetically, what if both the values of x we get from the quadratic formula are positive, then which one would we use to calculate concentrations?
Sat Jan 09, 2021 7:33 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Using bar or atm in Calculations
Replies: 4
Views: 17

### Re: Using bar or atm in Calculations

ATM is the standard unit of measure of pressure so we are most likely dealing with atm in chemistry, but I also agree with Sarah it depends on the units given in the problems.
Sat Jan 09, 2021 7:30 pm
Forum: Student Social/Study Group
Topic: New Year Resolutions?
Replies: 50
Views: 148

### Re: New Year Resolutions?

Prioritize mental health over everything and be more productive
Fri Jan 08, 2021 6:24 pm
Forum: Ideal Gases
Topic: Non-Ideal gases?
Replies: 24
Views: 93

### Re: Non-Ideal gases?

It is not mentioned in the syllabus so most likely not.
Fri Jan 08, 2021 6:18 pm
Forum: Administrative Questions and Class Announcements
Topic: Audio-Visual Topics
Replies: 13
Views: 42

### Re: Audio-Visual Topics

Last quarter what helped me the most with applying the concepts we learned in class was to go UAs workshops/step up session (one a week) and do practice problems in the textbook.
Thu Jan 07, 2021 6:02 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Equilibrium Constant Dependency
Replies: 2
Views: 23

### Equilibrium Constant Dependency

I know that the equilibrium constant is affected by the temperature, but why is it affected by temperature? Why is it only depended on temperature and not the the concentration of reactant we start off with.
Sat Dec 12, 2020 10:39 pm
Forum: Student Social/Study Group
Topic: Plans for Relaxing After Finals
Replies: 96
Views: 435

### Re: Plans for Relaxing After Finals

spending more time with my family and focusing on finishing my shows
Fri Dec 11, 2020 10:13 pm
Forum: Naming
Topic: Ferrate for iron
Replies: 5
Views: 47

### Re: Ferrate for iron

https://quizlet.com/462765872/ligand-na ... ds/?x=1jqt
here is another quizlet that someone in chem14a made that you can use!!!
Fri Dec 11, 2020 10:12 pm
Forum: Identifying Acidic & Basic Salts
Topic: Calculating Ka
Replies: 2
Views: 13

### Re: Calculating Ka

we are expected to just write the basic formula for a compound he gives us but are not expected to calculate it
Fri Dec 11, 2020 10:11 pm
Forum: Naming
Topic: Naming quizlet
Replies: 41
Views: 256

### Re: Naming quizlet

Thank you!!! This is really helpful
Fri Dec 11, 2020 10:09 pm
Forum: Student Social/Study Group
Topic: Struggling on topics
Replies: 6
Views: 47

### Re: Struggling on topics

You can rewatch lectures that pertain to the topic that you are struggling at, you can also watch YouTube videos online that explains the topic, do practice problem and compare your answers with solution manual and see what you did wrong
Fri Dec 11, 2020 10:08 pm
Forum: Identifying Acidic & Basic Salts
Topic: Memorizing Conjugates
Replies: 4
Views: 46

### Re: Memorizing Conjugates

Mari Williams 2k wrote:Going over them once or twice on quizlet is always helpful!

I agree with this! memorization is key to understanding common conjugates. There is also many quizlet available online so you do not have to worry about making one
Fri Dec 11, 2020 10:06 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: How to identify polydentates
Replies: 2
Views: 13

### Re: How to identify polydentates

Draw the lewis strcuture of the molecule
The ligand must have at least 2 atoms with lone pairs
Fri Dec 11, 2020 10:04 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Electron Geometry
Replies: 8
Views: 48

### Re: Electron Geometry

Electron geometry describes the arrangement of electron in a compound. Molecular geometry describes the arrangement of atoms, excluding lone pairs
Fri Dec 04, 2020 8:44 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Coordination Number for square planar molecule
Replies: 3
Views: 30

### Re: Coordination Number for square planar molecule

Coordination number is number of bonds (number of ligands) attached to the Transitional Metal. In the square planar complex, there are only 4 ligands attached and 2 lone pairs. So the coordination number is 4. REMEMBER NOT TO CONFUSED COORDINATION NUMBER WITH ELECTRON PAIRS OF TM!
Fri Dec 04, 2020 8:32 pm
Forum: Naming
Topic: sapling problem #1
Replies: 5
Views: 47

### Re: sapling problem #1

[Co(NH3)4Cl2]Cl In naming coordination compounds, ligands are named in alphabetical order first and then the TM with their oxidation number. From the compound above we can see that Cl2 and NH3 are the ligands. Since there are two cl anions it is dichloro and since there are 4 NH3 it is tetraammine. ...
Fri Dec 04, 2020 8:20 pm
Forum: Student Social/Study Group
Topic: Practice Exam for Final
Replies: 23
Views: 242

### Re: Practice Exam for Final

I don't think there any past final exams made available. However, in many of the workshops the questions are pulled directly from midterms and finals exams so you should be prepared by attending workshops. Also, you should do textbook problems to study. I think textbook problems are most similar to ...
Fri Dec 04, 2020 8:18 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Coordination Numbers
Replies: 8
Views: 55

### Re: Coordination Numbers

Coordination numbers are the numbers of bonds ligands forms with the transitional metal. Basically, they are the number of ligands bonded to TM. If you are still confused I think you should rewatch the Monday lecture (specifically the coordination compound part), Dr. Lavelle goes into dept about coo...
Fri Dec 04, 2020 8:13 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Textbook Question 9C:5
Replies: 2
Views: 16

### Re: Textbook Question 9C:5

When you draw out the lewis structure of CO3 2- you can see that there are two lewis structures. One structure has one CO double bond and two single CO bond. In this structure the Oxygen is capable of interacting with a transitional metal at two different places so it is classified as bidentate. The...
Fri Dec 04, 2020 8:01 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Oxidation Number
Replies: 6
Views: 59

### Re: Oxidation Number

Yes, you are correct. +3 is the oxidation state of the Co. NH3 is neutral and since the charge of two chlorine outside is -2 the compound charge must be +2. Therefore, since Cl inside has a charge of -1 you set this equation: X -1 = +2. The X aka the oxidation of Co is +3
Sun Nov 29, 2020 3:15 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Tips for VSEPR
Replies: 6
Views: 50

### Re: Tips for VSEPR

There is a lot of pre-made quizlets available that you can use as flashcard to study or as a practice test. I recommend this method because you can use quizlet on any browser anywhere
Sun Nov 29, 2020 3:13 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Sapling #17
Replies: 10
Views: 84

### Re: Sapling #17

I'm not really sure if we can find most favorable structure if there is no resonance. They all have equal net charges of 0 too so I think they are all favorable.
Sun Nov 29, 2020 3:08 pm
Forum: Administrative Questions and Class Announcements
Topic: Step Up/UA Sessions
Replies: 10
Views: 109

### Re: Step Up/UA Sessions

They are really helpful! I try to go to at least two workshops per week. I think the workshops problems are very similar to the structure. And they go step-by-step to make sure you understand the concept/problems
Sat Nov 28, 2020 7:33 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Axial vs Equatorial
Replies: 3
Views: 42

### Re: Axial vs Equatorial

Lone pairs have a stronger repelling effect than electrons in bonds. This is because lone pair have a larger electron cloud whereas bonding pair are being held in place by the two atom. Thus, to have the lowest energy/stable shape we need to have lone pairs as far away from other electron density re...
Sat Nov 28, 2020 7:29 pm
Forum: Student Social/Study Group
Topic: Finals!
Replies: 43
Views: 332

### Re: Finals!

Is there a possibility that the finals are going to be curved?
Sat Nov 28, 2020 7:27 pm
Forum: Lewis Structures
Topic: Delocalized Pi Bonds
Replies: 3
Views: 51

### Re: Delocalized Pi Bonds

Pi bonds are bonds formed by overlapping two parallel unhybridized p orbitals. If there are more than one adjacent orbitals the central atom can overlap with then its called a delocalized pi bonds. You can easily identify a delocalized pi bond if there is more than one adjacent atom from which a dou...
Sat Nov 28, 2020 7:09 pm
Forum: Student Social/Study Group
Topic: Midterm/Final Success?
Replies: 17
Views: 148

### Re: Midterm/Final Success?

Here are my tips: ATTEND UAs Sessions!! They go over previous years midterm/final questions so you get used Dr. Lavelle exam structure. Make a study guide using the unit outlines, lecture notes, and textbook I think textbook problems + UAs session problems are the most similar to the exam so priorit...
Sat Nov 28, 2020 7:06 pm
Forum: Administrative Questions and Class Announcements
Topic: 14B vs 14A
Replies: 12
Views: 157

### Re: 14B vs 14A

From what I heard Chem 14B material is harder. The textbook is same. Based on the syllabi for 14B there are Two 50 minute tests, One 2 hour midterm exam.
One 3 hour final exam.
Mon Nov 23, 2020 6:18 pm
Forum: Student Social/Study Group
Topic: Final Jitters
Replies: 226
Views: 35930

### Re: Final Jitters

I always have test anxiety right before any test. The best thing to do in my opinion is finding a study routine that works best for you (aka not procasinate and divide things up for study) and clearing your mind by doing what you like the most (watching movies, talking a walk, or sleeping)
Mon Nov 23, 2020 1:53 pm
Forum: Hybridization
Topic: Unhybridized orbitals
Replies: 1
Views: 36

### Unhybridized orbitals

What is the difference between unhybridized and hybridized orbitals? How do we determine how many unhybridized orbitals a molecule have?
Sun Nov 22, 2020 7:10 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Question About Seesaw Molecular Geometry
Replies: 3
Views: 26

### Re: Question About Seesaw Molecular Geometry

Lone pairs have a stronger repelling effect than electrons in bonds. This is because lone pair have a larger electron cloud whereas bonding pair are being held in place by the two atom. Thus, to have the lowest energy/stable shape we need to have lone pairs as far away from other electron density re...
Sat Nov 21, 2020 7:54 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: VSEPR
Replies: 4
Views: 96

### Re: VSEPR

I don't think so since it was only briefly mentioned in the textbook. Calculating it is a really complicated procedure that is beyond the scope of chemistry 14A so you don't have to worry about it Also, in order to analyze it we just look at the different colors. Since each color represent either th...
Sat Nov 21, 2020 5:31 pm
Forum: Polarisability of Anions, The Polarizing Power of Cations
Topic: Non-Polar Bonds
Replies: 3
Views: 41

### Re: Non-Polar Bonds

Based on the textbook and lectures, we should know that homonuclear diatomic molecules, benzene, methane, ethylene, and most organic molecules are non polars.
Sat Nov 21, 2020 5:25 pm
Forum: Dipole Moments
Topic: What are dipole moments
Replies: 9
Views: 71

### Re: What are dipole moments

http://www.chem.ucla.edu/~harding/IGOC/ ... oment.html
I was also struggling with understanding what dipole moments are and the website above helped me understand them better. I hope It can help!
Sat Nov 21, 2020 5:21 pm
Forum: Sigma & Pi Bonds
Topic: Are sigma and pi bonds the only types of bonds?
Replies: 2
Views: 33

### Are sigma and pi bonds the only types of bonds?

When I was looking up examples of sigma and pi bonds on google for a reference, I saw that there exist something called a delta bond. What exactly is a delta bond and how do we determine if a covalent compound has a delta bond? Also, are we expected to memorize delta bond for this course?
Sat Nov 21, 2020 5:14 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Which shapes to memorize
Replies: 11
Views: 133

### Re: Which shapes to memorize

If you are struggling with memorizing the molecular shapes, watch this video: https://www.youtube.com/watch?v=r2XmaiEC0Vw!
Sat Nov 21, 2020 5:10 pm
Forum: Student Social/Study Group
Topic: Study Tips for Final Exam
Replies: 57
Views: 397

### Re: Study Tips for Final Exam

Review your lecture notes, attends workshops/step sessions, practice problems from the book + homework, and if you are unsure about a topic don't be afraid to ask in the chemistry community !
Sun Nov 15, 2020 10:35 pm
Forum: Administrative Questions and Class Announcements
Topic: Midterm 2
Replies: 23
Views: 130

### Re: Midterm 2

Your TA will tell you when to start after making sure your desk is clear. After you are done, I am pretty sure you can just leave the zoom.
Sun Nov 15, 2020 10:32 pm
Forum: Octet Exceptions
Replies: 6
Views: 56

Basing of the problems in book about radicals, we should know that radicals have unpaired spins, be able to draw radicals/determine which structure is a radical, know that radicals are highly reactive/ can't be stored
Sun Nov 15, 2020 10:29 pm
Forum: Resonance Structures
Topic: Building Resonance Structures with Similar Formal Charges
Replies: 2
Views: 33

### Re: Building Resonance Structures with Similar Formal Charges

Least formal charges = more favorable. More electronegative atom should have the negative charge since it attracts electrons. If mot electronegative atom doesn't have the negative charge then its not favorable
Sat Nov 14, 2020 10:25 pm
Forum: Lewis Structures
Topic: Textbook 2C.3
Replies: 1
Views: 30

### Re: Textbook 2C.3

I have the same question about part c. How do we determine which atom bonds with which when we have three different atoms ?
Sat Nov 14, 2020 7:40 pm
Forum: Resonance Structures
Topic: Resonance
Replies: 19
Views: 100

### Resonance

How does resonance lowers energy and make molecules stable?
Sat Nov 14, 2020 7:35 pm
Forum: Administrative Questions and Class Announcements
Topic: Saving 14B for second enrollement
Replies: 4
Views: 75

### Re: Saving 14B for second enrollement

I'm also enrolling in 14B In second enrollment because there is usually enough seats because it is in such a high demands
Sat Nov 14, 2020 7:32 pm
Forum: Formal Charge and Oxidation Numbers
Topic: Helpful screenshot of oxidation rules from textbook
Replies: 7
Views: 63

### Re: Helpful screenshot of oxidation rules from textbook

one of the LA mentioned that oxidation states will not be tested. I think we just need to have a general understanding of them
Mon Nov 09, 2020 1:01 pm
Forum: Ionic & Covalent Bonds
Topic: Temporary vs Permanent Dipole Moments
Replies: 2
Views: 23

### Temporary vs Permanent Dipole Moments

What is the difference between temporary and permanent dipole moments? How are they both formed?
Mon Nov 09, 2020 12:59 pm
Forum: Dipole Moments
Topic: Dipole clarification
Replies: 6
Views: 31

### Re: Dipole clarification

I think it is both. They can occur between two ions in an ionic bond or between atoms in a covalent bond
Sun Nov 08, 2020 11:57 pm
Forum: Electronegativity
Topic: Periodic Trends
Replies: 9
Views: 40

### Re: Periodic Trends

"E stands for three things: Electronegativity, Electron affinity, and ionization Energy. All of these E’s increase going up and to the right of the periodic table." from MCAT mnemonics Periodic Trends
Sun Nov 08, 2020 3:39 pm
Forum: Trends in The Periodic Table
Topic: Electron Affinity
Replies: 4
Views: 32

### Electron Affinity

Why is the electron affinity for Carbon greater than nitrogen? Doesn't carbon occupying an orbital outside a closed shell means it farther from nucleus and requires energy.
Also, is the Nobel gas and C&N are the only exceptions in electron affinity?
Sat Nov 07, 2020 9:15 pm
Forum: Quantum Numbers and The H-Atom
Topic: Textbook 1D #21
Replies: 5
Views: 29

### Re: Textbook 1D #21

Just out of curiosity, If it is more than 5 orbitals, do we go by alphabet order or is there a specific order you need to go by
Sat Nov 07, 2020 9:12 pm
Forum: Student Social/Study Group
Topic: Veterans Day
Replies: 16
Views: 130

### Re: Veterans Day

Would the TA office hours and UA sessions will also be cancelled then?
Sat Nov 07, 2020 9:11 pm
Forum: Student Social/Study Group
Topic: Studying From Home
Replies: 91
Views: 465

### Re: Studying From Home

Hi ! I agree with you that studying at home has been really challenging for many. I think the best tip is to make a schedule and stick to it. Schedule for when you are going to do homework, study, or attend UA sessions. Also when studying follow the 45 min rule. Study for 45 min and take a 10 min br...
Mon Nov 02, 2020 1:22 pm
Forum: Resonance Structures
Topic: Delocalization of Electron
Replies: 2
Views: 41

### Delocalization of Electron

While watching today's lecture, I was confused about the concept of delocalization vs localization. Can someone explain to what each terms means in terms of resonance structures. Also, why does the delocalization of electrons increases a molecule or compound stability?
Mon Nov 02, 2020 1:18 pm
Forum: SI Units, Unit Conversions
Topic: Memorizing SI Units
Replies: 14
Views: 110

### Re: Memorizing SI Units

I also had trouble memorizing the SI units. I think what helped me was this mnemonic: Tera – The Giga – Great Mega – Man kilo – king hecto – henry’s deca – daughter BASE – Beth deci – drinks centi – cold mili – milk micro – μntil nano – nine pico – pm and since the SI unit increases/decreases by 10^...
Sat Oct 31, 2020 9:50 pm
Forum: Student Social/Study Group
Topic: Halloween!!!
Replies: 54
Views: 332

### Re: Halloween!!!

I did chemistry and LS30A homework for halloween
Sat Oct 31, 2020 9:47 pm
Forum: Trends in The Periodic Table
Topic: Ionization energy exceptions
Replies: 1
Views: 28

### Re: Ionization energy exceptions

I think for ionization energy is that B is lesser than Be and O is lesser than N because of the half filled and fully filled orbitals of N and Be is more stable (require more energy to ionize an electron)
Sat Oct 31, 2020 3:11 pm
Forum: Administrative Questions and Class Announcements
Topic: Midterm Scores
Replies: 4
Views: 61

### Re: Midterm Scores

Sometimes next week, I'm pretty sure since yesterday was the last day everyone took a makeup midterm
Tue Oct 27, 2020 9:20 pm
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: Sapling Homework #8 - Which number do we assign to n(1) versus n(2)
Replies: 4
Views: 44

### Re: Sapling Homework #8 - Which number do we assign to n(1) versus n(2)

434 nm is in the visible region so n=2 is the correct answer. For Balmer series, n=2 means the final energy level is 2. The electron would drop down to the energy level 2 after it becomes stable after exciting to some other higher energy level. The Rydberg Equation is frequency = R* ((1/n^2 for the ...
Mon Oct 26, 2020 2:59 pm
Forum: Administrative Questions and Class Announcements
Topic: Midterm 1 information
Replies: 7
Views: 101

### Re: Midterm 1 information

Yes it is during our TA discussion section but it will not be the same zoom link (another zoom link will be posted) If you have an external webcam, you can use that. If not, use a second device but make sure to use the zoom link provided on your TA Site for proctoring I'm not sure how many MC but ye...
Fri Oct 23, 2020 8:19 pm
Forum: Balancing Chemical Reactions
Topic: Balancing Equation Post Module Assessment
Replies: 2
Views: 44

### Balancing Equation Post Module Assessment

19. During a summer camping weekend 4 moles of butane (C4H10) gas were used for cooking. Chose the right balanced equation for the combustion of 4 moles of butane gas. What is the net number of moles of gas produced? A. 4C4H10(g) + 26O2(g) → 16CO2(g) + 20H2O(g); 6 B. 4C4H10(g) + 26O2(g) → 16CO2(g) +...
Fri Oct 23, 2020 6:46 pm
Topic: Midterm 1
Replies: 15
Views: 271

### Re: Midterm 1

Look at outline 1 + 2 on the Lavelle's website. It tell you exactly what you need to know!
Fri Oct 23, 2020 6:43 pm
Forum: Heisenberg Indeterminacy (Uncertainty) Equation
Topic: Showing our Work on the Midterm
Replies: 10
Views: 92

### Re: Showing our Work on the Midterm

My TA said we could use blank papers as scratch paper. Since the camera will be on, they will be able to see and approve your scratch paper.
Tue Oct 20, 2020 9:25 pm
Forum: DeBroglie Equation
Topic: Problem 1B.20
Replies: 3
Views: 47

### Re: Problem 1B.20

The Debroglie equation tells us that wavelength = h/mv Since the question states that velocity (distance/sec) is equal to the wavelength, we substitute velocity for wavelength. V = h/mv Isolate the V V^2 = h/m V= sqrt(h/m) Plug in the planks constant and the mass of an electron, which is also a cons...
Mon Oct 19, 2020 9:10 pm
Forum: Photoelectric Effect
Topic: Saplings #9
Replies: 3
Views: 57

### Re: Saplings #9

Here is my thought process (My value given for work function was different than yours): Given: the work function aka the threshold energy (3.200 x10^-19 J) We need to solve for max wavelength of E=hv function. Wavelength is inversely proportional to frequency. So max wavelength = min frequency. Min ...
Mon Oct 19, 2020 9:00 pm
Forum: Photoelectric Effect
Topic: textbook solutions
Replies: 2
Views: 37

### Re: textbook solutions

Page C57 of the textbook in sapling includes the solutions to odd numbered exercises
Mon Oct 19, 2020 2:06 pm
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: Sapling week 2/3 question 8
Replies: 3
Views: 37

### Re: Sapling week 2/3 question 8

What is the question asking you to calculate?
Sun Oct 18, 2020 3:08 pm
Forum: Photoelectric Effect
Topic: Short/high wavelength
Replies: 7
Views: 57

### Re: Short/high wavelength

I think it because of the equation E=H*V. This equation shows that energy per photon is directly proportional to Frequency (V). So as frequency increases, energy per photon is higher. In addition, from the equation c= wavelength * frequency, frequency is inversely proportional to wavelength. So as f...
Sat Oct 17, 2020 8:43 pm
Forum: DeBroglie Equation
Topic: homework problem 1B.23
Replies: 1
Views: 31

### Re: homework problem 1B.23

First step is to convert every units into SI units. In this case, we were only given 100 pm. Since the meter is the si unit, you convert it into m. (1 picometer = 10^-12 meter). THEN use the the formula for velocity ( v=h/mλ) to solve. h is a constant = 6.62626*10^-34 J*s m is the mass of the neutro...
Sat Oct 17, 2020 8:32 pm
Forum: General Science Questions
Topic: Kelvin
Replies: 8
Views: 60

### Re: Kelvin

In the SI system the unit for Kelvin is just K (make sure It is capital K). As for Celsius, it is °C . For Fahrenheit , it is °F. I think the reason why Kelvin doesn't have a degree may have something to do with the fact that this is an absolute scale
Thu Oct 15, 2020 9:52 pm
Forum: Administrative Questions and Class Announcements
Topic: Matthew's Workshop - Week 2
Replies: 1
Views: 312

### Re: Matthew's Workshop - Week 2

Could you possibly post the solutions for the problems? I want to compare my answers to see if I did it right. Thank you!
Thu Oct 15, 2020 9:49 pm
Forum: Administrative Questions and Class Announcements
Topic: Where can I buy a webcam for a reasonable price?
Replies: 60
Views: 1099

### Where can I buy a webcam for a reasonable price?

I have been looking up prices for webcam on amazon but all of them are above \$35 and my budge is around \$25. Anybody know where I can find a webcam for cheap price? if you purchased one, can you drop the link for the website below
Fri Oct 09, 2020 5:36 pm
Forum: Molarity, Solutions, Dilutions
Topic: Concentration Calculations
Replies: 11
Views: 3063

### Re: Concentration Calculations

To find the molarity of Na2CO3 you divide 2.111 grams of solid (the solid here is NA2CO3 since this is the solute in the aqueous solution) by its molar mass to find moles. Moles = Grams /molar mass
Then you do moles/volume to find the molarity
Thu Oct 08, 2020 9:27 pm
Forum: Empirical & Molecular Formulas
Topic: Arrangement of elements/polyatomic ions
Replies: 2
Views: 44

### Arrangement of elements/polyatomic ions

When we find the moles needed for each components of a formula, how should we arrange the equation? For example F1. We found the citral empirical formula has 10 carbon atoms, 1 oxygen atoms, and 16 Hydrogen atoms. In what order should we write the formula? Or does it even matter if we write in rando...
Thu Oct 08, 2020 9:19 pm
Forum: Balancing Chemical Reactions
Topic: Fundamental Question E.17
Replies: 3
Views: 44

### Re: Fundamental Question E.17

C. Number of objects (atoms) = amounts in moles x number of objects per mole (avogradros constant= 6.0221x10^23) In this case since they both contain the same number of objects (atoms), the amount in moles (aka number of moles of atoms) will both be equal. So the answer is both. You can try to plug ...
Wed Oct 07, 2020 7:40 pm
Forum: Accuracy, Precision, Mole, Other Definitions
Topic: Exercise E.9
Replies: 6
Views: 133

### Re: Exercise E.9

Heptahydrate means 7 water molecules. SO 7H20 Hepta= Seven Hydrates= a compound, typically a crystalline one like this epsom salt, in which water molecules are chemically bound to another compound (MgS04) or an element Basically anytime you see a hydrate you know that H20 is going to be in the formula
Tue Oct 06, 2020 8:57 pm
Forum: General Science Questions
Topic: Office Hours
Replies: 5
Views: 43

### Re: Office Hours

On Monday's office hour we just went over the syllabus. But I do recommend going to his office hours when you have time since he is going over materials/topics.
Also, to add on to that question, is the discussion from the Monday office hour the same as Thursday?
Tue Oct 06, 2020 8:51 pm
Forum: General Science Questions
Topic: Taking Notes on Textbook Readings
Replies: 13
Views: 112

### Re: Taking Notes on Textbook Readings

Personally, I like to take notes when reading the textbook materials. In my opinion, it helps me to remember what is important in each sections of a chapter and the important formulas.This is way when I am for the midterm/exam I don't need to look at the textbook and scroll down millions of pages to...