Search found 37 matches
- Sat Jun 02, 2018 9:54 am
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: coordination number vs. oxidation number [ENDORSED]
- Replies: 4
- Views: 1185
coordination number vs. oxidation number [ENDORSED]
what is the difference between these 2 and how do we find them for coordination compounds?
- Sat May 26, 2018 3:49 pm
- Forum: Hybridization
- Topic: basics of hybridization
- Replies: 18
- Views: 2526
basics of hybridization
I am a bit confused on hybridization. can anyone direct me to a video or give an explanation of what it is and how to solve problems involving it? thank you :)
- Fri May 25, 2018 7:16 am
- Forum: Resonance Structures
- Topic: ranking
- Replies: 11
- Views: 1541
Re: ranking
by the formal charge. The most important is the lowest energy and the one with formal charges on each element closest to zero as possible.
- Wed May 23, 2018 7:15 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: VSEPR on test 3?
- Replies: 3
- Views: 500
Re: VSEPR on test 3?
just lewis structures
- Wed May 16, 2018 7:49 am
- Forum: Bond Lengths & Energies
- Topic: test 3 [ENDORSED]
- Replies: 3
- Views: 451
test 3 [ENDORSED]
does test 3 include only outline 3 or does it also include outline 4?
- Wed May 09, 2018 1:05 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Midterm Significant Figures [ENDORSED]
- Replies: 4
- Views: 654
Re: Midterm Significant Figures [ENDORSED]
you can lose up to 1 point on each page of the test if sig figs are wrong i think
- Wed May 09, 2018 1:02 pm
- Forum: General Science Questions
- Topic: Past Midterm Question
- Replies: 2
- Views: 524
Re: Past Midterm Question
it is because the question is saying if you add more photons of the same energy will electron speed increase. it won't because you are changing intensity but not the actual energy of each question. the wording is confusing. it is not saying the photons each have more energy, it is saying there are m...
- Wed May 09, 2018 7:49 am
- Forum: Heisenberg Indeterminacy (Uncertainty) Equation
- Topic: conceptual q (based on q 1.43)
- Replies: 1
- Views: 301
Re: conceptual q (based on q 1.43)
the uncertainty is change in position so delta x. if you know delta x you can solve for delta v which is uncertainty in velocity.
since we are solving for an electron, we know its mass, and we are given position so we can find v based on the equation
since we are solving for an electron, we know its mass, and we are given position so we can find v based on the equation
- Tue May 08, 2018 8:02 pm
- Forum: General Science Questions
- Topic: Past Midterm Question
- Replies: 2
- Views: 524
Re: Past Midterm Question
yes, because higher energy photons would cause electrons to be ejected at a higher velocity.
Ephoton= work function + KE of electron
work function is constant
so as Ephoton increases, KE and thus speed of electron increases
so i am not sure why the answer is no
Ephoton= work function + KE of electron
work function is constant
so as Ephoton increases, KE and thus speed of electron increases
so i am not sure why the answer is no
- Mon May 07, 2018 7:03 am
- Forum: Photoelectric Effect
- Topic: Photoelectric Problems
- Replies: 4
- Views: 643
Re: Photoelectric Problems
it is conceptual but also need to do problems involving equation
energy of photon = work function + KE of ekectron
1/2mv^2
E=hv
these are equations used for the calculations
energy of photon = work function + KE of ekectron
1/2mv^2
E=hv
these are equations used for the calculations
- Sun May 06, 2018 4:37 pm
- Forum: Student Social/Study Group
- Topic: Practice Test (Lyndon) Answer Key
- Replies: 1
- Views: 589
Re: Practice Test (Unicorn) Answer Key
search the code word (a mystical creature with one horn) and select the endorsed post
- Sun May 06, 2018 7:40 am
- Forum: Photoelectric Effect
- Topic: 1.69
- Replies: 2
- Views: 412
Re: 1.69
what part are you confused on for this problem? A good hint is to use the equations Ephoton=work function + KE of electron
and E=hv
and E=hv
- Sat May 05, 2018 8:28 am
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Electron configuration for P^3- [ENDORSED]
- Replies: 2
- Views: 388
Re: Electron configuration for P^3- [ENDORSED]
add 3 electrons to the outermost shell of the neutral ground state configuration
- Sat May 05, 2018 8:27 am
- Forum: Ionic & Covalent Bonds
- Topic: cation vs anion
- Replies: 14
- Views: 3747
Re: cation vs anion
cation ion is + charged like Ca2+ anion is - charged like Cl- I remember it by anion starts with a, just like antonym, and the antonym is the opposite so I think of negative. Any type of memory cue that will make sense to you will work. Maybe think how cats are positively cute, so cations are +. wha...
- Fri May 04, 2018 9:46 pm
- Forum: Properties of Light
- Topic: Sig Figs [ENDORSED]
- Replies: 3
- Views: 550
Re: Sig Figs [ENDORSED]
I would say yes. it is good to get into the habit of it anyways.
- Thu May 03, 2018 3:03 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: 2.25 [ENDORSED]
- Replies: 3
- Views: 508
Re: 2.25 [ENDORSED]
helium is also in the 1s orbital and has 2 electrons, so therefore the 1s orbital can have 2 electrons despite hydrogen having only one.
- Wed May 02, 2018 8:58 pm
- Forum: Trends in The Periodic Table
- Topic: electron affinity vs ionization energy
- Replies: 2
- Views: 1390
electron affinity vs ionization energy
I am a bit confused on the difference between these 2 concepts and the patterns in the table for each. Question 2.67 talks about which element will have higher electron affinity and it seems to follow the same trend as ionization energy. is this a trend that we can follow throughout the table or are...
- Wed May 02, 2018 8:53 pm
- Forum: Trends in The Periodic Table
- Topic: homework 2.59
- Replies: 3
- Views: 355
Re: homework 2.59
go to the chem website and click solution manual errors. but also they do not have the same ionic radius, because ionic radius decreases across a period and those elements are all in the same period
- Wed May 02, 2018 5:33 pm
- Forum: Trends in The Periodic Table
- Topic: Removing the 2nd electron is always harder [ENDORSED]
- Replies: 5
- Views: 1622
Re: Removing the 2nd electron is always harder [ENDORSED]
the first electron removed is the outermost, meaning it is farthest from the nucleus. The nucleus is positive and electrons are negative, meaning they are attracted to each other. The outermost electron is easiest to take away because the strength of attraction to the nucleus is least because the el...
- Wed May 02, 2018 5:29 pm
- Forum: Significant Figures
- Topic: Use of Appropriate Sig Figs
- Replies: 2
- Views: 593
Re: Use of Appropriate Sig Figs
yep! always use the least number of sig figs in the given in your final answer :)
- Wed May 02, 2018 9:48 am
- Forum: Heisenberg Indeterminacy (Uncertainty) Equation
- Topic: Example 1.7
- Replies: 2
- Views: 516
Re: Example 1.7
because its +or- 1 it is really 2 because it is either plus 1 or minus 1 so the overall range is actually 2. does that make sense? like if a dog's weight fluctuated around 50 lbs with +-1, then its weight is either 49,50,or 51 lbs, but the overall range in the uncertainty of its weight at a time is ...
- Fri Apr 27, 2018 7:36 am
- Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
- Topic: Wavelengths and their corresponding electromagnetic spectrum
- Replies: 2
- Views: 390
Re: Wavelengths and their corresponding electromagnetic spectrum
I would say know that 400nm-700nm is visible light and then radio and infared are longer and uv, xray and gamma are shorter. knowing the order is more important than exact numbers i think.
- Fri Apr 27, 2018 7:34 am
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: Wave peak differences
- Replies: 2
- Views: 351
Re: Wave peak differences
if the peaks are not in sync and thus the waves not in sync then it will always be destructive interference.
- Fri Apr 27, 2018 7:33 am
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: Cutoff for wavelike properties [ENDORSED]
- Replies: 2
- Views: 380
Re: Cutoff for wavelike properties [ENDORSED]
I think he said 10^-15 is the cutoff. anything below that is too small.
- Tue Apr 24, 2018 7:59 am
- Forum: Photoelectric Effect
- Topic: increasing frequency/ light intensity
- Replies: 5
- Views: 1363
Re: increasing frequency/ light intensity
increasing the frequency will allow electrons to be emitted and be emitted with a higher speed. if the frequency is good enough to eject an electron, then increasing brightness will increase the number of electrons ejected, because there will be more photons and photons act in 1:1 ratio with electro...
- Mon Apr 23, 2018 10:16 pm
- Forum: Heisenberg Indeterminacy (Uncertainty) Equation
- Topic: test 2
- Replies: 2
- Views: 384
Re: test 2
I do not think this is in test 2. Test 2 includes only up to 1.5 and the uncertainty equation is 1.6
- Mon Apr 23, 2018 10:13 pm
- Forum: Photoelectric Effect
- Topic: increasing frequency/ light intensity
- Replies: 5
- Views: 1363
Re: increasing frequency/ light intensity
increasing the frequency changes the wavelength and thus changes the type of light and energy of the light.
increasing the intensity is just increasing the number of photons and essentially the brightness.
increasing the intensity is just increasing the number of photons and essentially the brightness.
- Mon Apr 23, 2018 10:11 pm
- Forum: Photoelectric Effect
- Topic: equation for the photoelectric effect
- Replies: 1
- Views: 252
Re: equation for the photoelectric effect
work plus KE is what you use to figure out the energy of the photon if you are given work function and velocity of the electron that was ejected.
photon energy minus KE is what you use to figure out work function/minimum light needed to eject an electron. hope that helps!
photon energy minus KE is what you use to figure out work function/minimum light needed to eject an electron. hope that helps!
- Thu Apr 12, 2018 3:41 pm
- Forum: Properties of Electrons
- Topic: Homework 2?
- Replies: 1
- Views: 195
Re: Homework 2?
He said homework can be anything recently covered, so you can do work from the fundamentals and just problems from chapter 1 that you recognize from class. He said any 7 questions that you have not done are okay I believe.
- Thu Apr 12, 2018 3:35 pm
- Forum: Properties of Light
- Topic: Intensity in terms of Quantum Mechanics and Classical Mechanics
- Replies: 2
- Views: 1469
Re: Intensity in terms of Quantum Mechanics and Classical Mechanics
I believe in classical mechanics, the intensity of a wave is based on amplitude, or height of the wave. In quantum mechanics, and with light, the intensity of the wave is not correlated to amplitude, but rather by the frequency/wavelength of each photon. In the photoelectric effect, it is not the nu...
- Thu Apr 12, 2018 2:25 pm
- Forum: SI Units, Unit Conversions
- Topic: Correct Units?? [ENDORSED]
- Replies: 8
- Views: 929
Correct Units?? [ENDORSED]
How do we know whether a formula needs g or kg? some formulas assume g while others assume kg. What is a good rule of thumb? Is it normally that mechanics equations such as 1/2mv used kg whereas other equations in quantum mechanics use grams?
- Thu Apr 12, 2018 8:42 am
- Forum: Properties of Light
- Topic: HW 1.7 (speed of light) clarification
- Replies: 4
- Views: 272
Re: HW 1.7 (speed of light) clarification
I think he said to use whatever value the question gives, so on tests he will probably tell us which value to use.
- Thu Apr 12, 2018 8:38 am
- Forum: SI Units, Unit Conversions
- Topic: Moles mols mol? [ENDORSED]
- Replies: 21
- Views: 9381
Re: Moles mols mol? [ENDORSED]
Hello! I had a quick question for L1 in the fundamentals section outline. Without using a calculator, estimate what amount of Br2 (in moles) can be obtained from 0.30 mol ClO2 in the reaction 6 ClO21g2 2 BrF31l2 S 6 ClO2F1s2 Br21l2. for this they simply want you to see that Br2 is in a 1:6 rati...
- Thu Apr 12, 2018 8:32 am
- Forum: Molarity, Solutions, Dilutions
- Topic: Mass percentage
- Replies: 8
- Views: 1057
Re: Mass percentage
I would say most likely that wouldn't happen as that does not make sense. If they do not add up to 100 maybe double check your math, or maybe another element is simply not being mentioned.
- Sat Apr 07, 2018 5:09 pm
- Forum: SI Units, Unit Conversions
- Topic: writing out conversions in one long line vs. steps
- Replies: 16
- Views: 1498
writing out conversions in one long line vs. steps
do people find it more helpful to write multiple conversions in one step or to break the problem up into multiple steps? I get confused with it and wanted to see what other people do/prefer/think is easiest and allows one to better understand the concept behind it. any help would be appreciated :)))
- Sat Apr 07, 2018 5:02 pm
- Forum: Empirical & Molecular Formulas
- Topic: Determining Molecular Formula Based on Name of Molecule [ENDORSED]
- Replies: 5
- Views: 543
Re: Determining Molecular Formula Based on Name of Molecule [ENDORSED]
does it matter the order of the atoms in the formula? Like CHO vs OHC? (i know this is a bad example). and if order matters then how do we know which to put first? basically whichever is listed first?
- Sat Apr 07, 2018 5:00 pm
- Forum: Significant Figures
- Topic: 300 vs 300. [ENDORSED]
- Replies: 8
- Views: 4794
Re: 300 vs 300. [ENDORSED]
so the decimal is what sig figs revolves around correct? aka when in doubt just look and see the importance of a decimal?