Search found 38 matches

by John_Tran_1L
Fri Nov 20, 2020 12:46 pm
Forum: Octet Exceptions
Topic: Octet Rule Exceptions
Replies: 20
Views: 139

Re: Octet Rule Exceptions

From my memory, I believe Phosphorus, Sulfur, and Chlorine have expanded octets, meaning they can contain more than 8 valence electrons. There are also molecules that don't have to abide by the octet rule, they are known as Hydrogen and Helium.
by John_Tran_1L
Fri Nov 20, 2020 12:43 pm
Forum: *Liquid Structure (Viscosity, Surface Tension, Liquid Crystals, Ionic Liquids)
Topic: Boiling and Melting point
Replies: 15
Views: 60

Re: Boiling and Melting point

Both melting and boiling point increase when the intermolecular forces are stronger.
by John_Tran_1L
Fri Nov 20, 2020 12:42 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: LDF forces
Replies: 9
Views: 43

Re: LDF forces

It is known that LDF is in all forces, but it is strongest in non-polar molecules.
by John_Tran_1L
Fri Nov 20, 2020 12:42 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Exercise 2A.15 a
Replies: 4
Views: 26

Re: Exercise 2A.15 a

Correct! S is near a full valence shell, so it will be greedy and take the other valence electrons.
by John_Tran_1L
Fri Nov 20, 2020 12:41 pm
Forum: Dipole Moments
Topic: Why are poles only "di"?
Replies: 4
Views: 43

Re: Why are poles only "di"?

I believed that its called dipole, because "di" refers to two sides of a molecule and "pole" refers to polar. To conclude, dipole refers to both (2) sides of a polar molecule.
by John_Tran_1L
Fri Nov 13, 2020 5:34 pm
Forum: Student Social/Study Group
Topic: Midterm 2
Replies: 31
Views: 202

Re: Midterm 2

Its safe to assume that we should know the last 8 bullet points of the outline.
by John_Tran_1L
Fri Nov 13, 2020 5:33 pm
Forum: Student Social/Study Group
Topic: grade worries
Replies: 97
Views: 582

Re: grade worries

I agree with others, I've been worrying about the weight of midterm grades for awhile.
by John_Tran_1L
Fri Nov 13, 2020 5:31 pm
Forum: Trends in The Periodic Table
Topic: atomic radii
Replies: 10
Views: 30

Re: atomic radii

I believe that we should at least know the trend of atomic radii: where it decreases from right to left and up to down on the periodic table.
by John_Tran_1L
Fri Nov 13, 2020 5:27 pm
Forum: Student Social/Study Group
Topic: Midterm 2
Replies: 22
Views: 79

Re: Midterm 2

For me, I just attend UA workshop/step up sessions to relearn the information from Lavelle's lecture!
by John_Tran_1L
Fri Nov 13, 2020 5:24 pm
Forum: Lewis Structures
Topic: Chemical Names
Replies: 9
Views: 32

Re: Chemical Names

It wouldn't't be fair for Lavelle to assume that we all know the concept "nomenclature," so I think we can safely assume that we won't have to know "Chemical names" for the second midterm.
by John_Tran_1L
Fri Nov 13, 2020 5:21 pm
Forum: Student Social/Study Group
Topic: Post All Chemistry Jokes Here
Replies: 8205
Views: 1433394

Re: Post All Chemistry Jokes Here

Man: Are there any good chemistry jokes out there?
Me: I don't zinc so?
by John_Tran_1L
Sat Nov 07, 2020 9:51 pm
Forum: Lewis Structures
Topic: Difference in ionic and covalent Lewis structures
Replies: 9
Views: 43

Re: Difference in ionic and covalent Lewis structures

ionic bonds give and take electrons while covalent share electrons.
by John_Tran_1L
Sat Nov 07, 2020 9:49 pm
Forum: Photoelectric Effect
Topic: Units for energy
Replies: 11
Views: 85

Re: Units for energy

1/s = Hz
1 Joule= 1 kg m^2/s^2
by John_Tran_1L
Sat Nov 07, 2020 9:47 pm
Forum: Administrative Questions and Class Announcements
Topic: Midterm Curve?
Replies: 12
Views: 108

Re: Midterm Curve?

Based on previous years and the posts above, it's safe to assume that there will not be a curve.
by John_Tran_1L
Sat Nov 07, 2020 9:47 pm
Forum: Student Social/Study Group
Topic: Veterans Day
Replies: 16
Views: 107

Re: Veterans Day

I assume that there will be no lecture because my other classes do not have lectures on Wednesday.
by John_Tran_1L
Sat Nov 07, 2020 9:45 pm
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: Can you have the same 3 quantem number but not the 4 same quantem numbers
Replies: 12
Views: 57

Re: Can you have the same 3 quantem number but not the 4 same quantem numbers

It is possible to have the same 3 quantum numbers, but it is not possible to have 4 of the same. The four quantum numbers determine the magnetic spin (1/2 or -1/2.)
by John_Tran_1L
Sat Nov 07, 2020 9:44 pm
Forum: Lewis Structures
Topic: lewis structure
Replies: 10
Views: 62

Re: lewis structure

The formula to calculate formal charge is: Formal Charge = Valence electrons - (shared electrons/2 + lone pairs)!
by John_Tran_1L
Sun Nov 01, 2020 1:03 pm
Forum: DeBroglie Equation
Topic: When to Use De Broglie
Replies: 16
Views: 96

Re: When to Use De Broglie

There are a couple ways of using DeBroigle's euqation, first if you are given a wavelength and are asked to calculate the velocity of an ejected electron. Second if you are given the velocity and asked to calculate the wavelength of an ejected electron.
by John_Tran_1L
Sun Nov 01, 2020 1:00 pm
Forum: Ionic & Covalent Bonds
Topic: Homework due date
Replies: 40
Views: 186

Re: Homework due date

The homework will be due tonight (Sunday) at 11:59pm, good luck!
by John_Tran_1L
Sun Nov 01, 2020 12:59 pm
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: l=4
Replies: 13
Views: 82

Re: l=4

I agree with the posts above, it is theoretically possible, but there are no elements in the periodic table that corresponds to l=4.
by John_Tran_1L
Sun Nov 01, 2020 12:57 pm
Forum: Balancing Chemical Reactions
Topic: Balancing Equations Coefficient Question
Replies: 15
Views: 68

Re: Balancing Equations Coefficient Question

To correctly balance an equation with fractions as stoichiometric coefficients, you must multiply every coefficient with the demoniator of the fraction. This action causes every coefficient (including the faction) to become a whole number.
by John_Tran_1L
Sun Nov 01, 2020 12:56 pm
Forum: Photoelectric Effect
Topic: Sampling Hw #19
Replies: 2
Views: 19

Re: Sampling Hw #19

I agree with the post above, for this problem you should definitely use the DeBroigle equation and alternate between the masses of the particles you are trying to calculate. This in turn, will give you different values for the specific particles.
by John_Tran_1L
Sat Oct 24, 2020 11:27 am
Forum: DeBroglie Equation
Topic: Practice Problem
Replies: 7
Views: 44

Re: Practice Problem

I agree with every post/reply above me! Unit conversion is an essential topic, as mentioned in Lavelle's recent lecture.
by John_Tran_1L
Sat Oct 24, 2020 11:26 am
Forum: Significant Figures
Topic: Sig Figs
Replies: 8
Views: 68

Re: Sig Figs

In chemistry, sig figs should be applied to everything for maximum accuracy!
by John_Tran_1L
Sat Oct 24, 2020 11:24 am
Forum: Quantum Numbers and The H-Atom
Topic: Rydberg Constant
Replies: 13
Views: 92

Re: Rydberg Constant

In one of Lavelle's recent lectures, I recall him using the number 3.29 X 10^15 Hz as the constant.
by John_Tran_1L
Sat Oct 24, 2020 11:23 am
Forum: Student Social/Study Group
Topic: How are you studying?
Replies: 196
Views: 836

Re: How are you studying?

I comprehends subjects more when written out. In other words, I rewatch the lectures and retake notes as a refresher, I then look up worksheets regarding each topic (ie: work function, molar mass, atomic spectra etc....)
by John_Tran_1L
Sat Oct 24, 2020 11:21 am
Forum: Einstein Equation
Topic: Usage of E=hv
Replies: 10
Views: 87

Re: Usage of E=hv

To compute the energy of an incoming photon use E=hv, De Broigle's equation is used for electrons.
by John_Tran_1L
Sat Oct 17, 2020 10:59 pm
Forum: SI Units, Unit Conversions
Topic: Given Unit Conversions?
Replies: 6
Views: 38

Re: Given Unit Conversions?

I believe that my TA said that the constants (Avo. number, Speed of light, Plank's constant...) will be given to us on the test. I also heard that the periodic table will be accessible as well.
by John_Tran_1L
Sat Oct 17, 2020 10:57 pm
Forum: Einstein Equation
Topic: What are the units for E
Replies: 16
Views: 117

Re: What are the units for E

The equation can be manipulated to to solve for either "E" for energy or for "wavelength." When solving for energy, you would use joules. When given the energy at any question, you would have to solve for "wavelength" meaning your units would be in M for meters, the ans...
by John_Tran_1L
Sat Oct 17, 2020 10:54 pm
Forum: Properties of Electrons
Topic: Electrons ejected
Replies: 7
Views: 31

Re: Electrons ejected

It really depends on the amount of energy in the photons. If there are 3 photons with insufficient energy (to give off an electron) then no electrons would be given off. This is due to the fact that increase of intensity in the light source only increases the quantity of photons, NOT the energy of p...
by John_Tran_1L
Sat Oct 17, 2020 10:52 pm
Forum: Properties of Light
Topic: Intensity v Energy
Replies: 18
Views: 130

Re: Intensity v Energy

The intensity of the light source refers to the "amplitude" meaning that the amplitude affect the number of photons. The wavelength refers to the energy level per photon. In other words, the intensity refers to "how many" photons there are in the light source and the wavelength r...
by John_Tran_1L
Sat Oct 17, 2020 10:47 pm
Forum: Properties of Light
Topic: Study Advice
Replies: 46
Views: 181

Re: Study Advice

Step-up sessions are for individuals that need more help on the basics fundamentals of the week's lecture topics ( in this case it would be about photoelectric energy, wavelengths, atomic spectra etc...) and Workshops are for those students that would want more difficult questions in regards to the ...
by John_Tran_1L
Thu Oct 08, 2020 10:55 am
Forum: Student Social/Study Group
Topic: Office Hours
Replies: 7
Views: 54

Re: Office Hours

As we can tell by the previous officious hours this year, many people come in to listen or gather information! You are not obligated to speak or even have your camera on! Office hours are useful as they will give you information, it also helps to build a relationship with Lavelle himself :)
by John_Tran_1L
Thu Oct 08, 2020 10:51 am
Forum: General Science Questions
Topic: Rusty on High School Chem [ENDORSED]
Replies: 200
Views: 141256

Re: Rusty on High School Chem [ENDORSED]

I would recommend watching the modules and taking the post assessment tests that Lavelle emailed to us. Then I also recommend attending the step up sessions, these sessions focus on honing basic skills that the four modules and fundamentals covered.
by John_Tran_1L
Thu Oct 08, 2020 10:42 am
Forum: Administrative Questions and Class Announcements
Topic: Step Up Sessions
Replies: 71
Views: 4370

Re: Step Up Sessions

I've been to a step up sessions everyday. The TA's (or helpers idrk what they call themselves) begin by sending/displaying a worksheet of previous homework/midterm questions. I've come to find them helpful as a beginner in chemistry, but I do recommend to have a slight knowledge of basic chemistry b...
by John_Tran_1L
Thu Oct 08, 2020 10:37 am
Forum: SI Units, Unit Conversions
Topic: Significant Figures Using the Periodic Table
Replies: 13
Views: 83

Re: Significant Figures Using the Periodic Table

To receive the most accurate answer, u should apply the atomic weights as given through the periodic table (avoid using whole numbers, they can mess you up.)
by John_Tran_1L
Thu Oct 08, 2020 10:34 am
Forum: Significant Figures
Topic: Integers and Sig Figs
Replies: 4
Views: 81

Re: Integers and Sig Figs

Integers are numbers that do not contain the decimal (.) point, while sig figs are numbers that focus on the meaningful composition. While 5 and show little/no change in value, I believe that sig figs should be sought out carefully because they can change the outcome of the solution.
by John_Tran_1L
Thu Oct 08, 2020 10:29 am
Forum: Molarity, Solutions, Dilutions
Topic: Sapling HW Question 6
Replies: 4
Views: 53

Re: Sapling HW Question 6

I agree with the posts above, to obtain the most accurate results you take into consideration the significant figures (a.k.a .04523.) The answer in the end should be 102.8.

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