Search found 39 matches
- Fri Nov 08, 2019 6:24 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: VESPR
- Replies: 5
- Views: 412
Re: VESPR
Just a heads up, you'll have to memorize the VSEPR chart.
- Fri Nov 08, 2019 6:19 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Difference between molecular and electron geometry?
- Replies: 3
- Views: 56042
Re: Difference between molecular and electron geometry?
Essentially, electron geometry includes lone pairs while molecular geometry excludes lone pairs in the VSEPR chart.
- Fri Nov 08, 2019 6:15 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Polar v. Nonpolar
- Replies: 11
- Views: 2178
Re: Polar v. Nonpolar
To determine whether the dipoles are polar or not, you're also going to need the shape of the molecule. To double check, you could find an electronegativity chart and check to see if the difference between values surpass the nonpolar covalent point.
- Fri Nov 08, 2019 6:09 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Formal Charge
- Replies: 9
- Views: 1478
Re: Formal Charge
For most stable structures, the more electronegative atom should typically be the one with the negative formal charge and the opposite is true for the opposite case.
- Thu Nov 07, 2019 6:01 pm
- Forum: General Science Questions
- Topic: Week 6 homework problems
- Replies: 7
- Views: 577
Re: Week 6 homework problems
So... same chapter?
- Thu Oct 31, 2019 10:48 pm
- Forum: Ionic & Covalent Bonds
- Topic: Format of midterm?
- Replies: 12
- Views: 727
Re: Format of midterm?
Given that there are only 8 questions, the chances of there being a multiple choice question part is highly unlikely. So as everyone has stated, it's almost definitely gonna be a majority, if not all, free-response questions.
- Thu Oct 31, 2019 10:45 pm
- Forum: Ionic & Covalent Bonds
- Topic: Radicals
- Replies: 9
- Views: 667
Re: Radicals
As being mentioned above, radicals are unpaired electrons that can affect DNA. Thinking of this biologically, the possibility of mutations and such occurring in the DNA due to unpaired electrons is much more likely. A way to think of it is to imagine a population where there is just enough food for ...
- Thu Oct 31, 2019 10:38 pm
- Forum: Ionic & Covalent Bonds
- Topic: Valence Electrons?
- Replies: 15
- Views: 1136
Re: Valence Electrons?
[Continuation of last explanation]
For this reason, I believe that the problems will inform you as to what the charges are for the transition metals, disregarding a few of the ones with fixed charges. (For anyone who feels, or is more confident, please feel free to pitch in on this matter!)
For this reason, I believe that the problems will inform you as to what the charges are for the transition metals, disregarding a few of the ones with fixed charges. (For anyone who feels, or is more confident, please feel free to pitch in on this matter!)
- Thu Oct 31, 2019 10:32 pm
- Forum: Ionic & Covalent Bonds
- Topic: Valence Electrons?
- Replies: 15
- Views: 1136
Re: Valence Electrons?
From my understanding of transition metals, there is no set number of valence electrons for each individual atom within these metals as their electrons can be configured in a variety of ways allowing them to have a range of possible numbers for valence electrons.
- Thu Oct 31, 2019 10:18 pm
- Forum: Ionic & Covalent Bonds
- Topic: Midterm
- Replies: 28
- Views: 1448
Re: Midterm
Aforementioned, the midterm covers the three main topics: Fundamentals, Chemical Bonds, and the Quantum World. So it's highly recommended to study those sections and do the review problems!
- Fri Oct 25, 2019 9:49 am
- Forum: Trends in The Periodic Table
- Topic: Calculated vs Observed Value
- Replies: 6
- Views: 581
Re: Calculated vs Observed Value
In quick summary, in comparison to other periodic patterns, electronegativity is able to be calculated as elements have set electronegative charges.
- Fri Oct 25, 2019 9:17 am
- Forum: Trends in The Periodic Table
- Topic: blocks
- Replies: 13
- Views: 705
Re: blocks
I would say yes, especially given that you have to be able to write electronic configurations.
- Fri Oct 25, 2019 9:12 am
- Forum: Trends in The Periodic Table
- Topic: Ionization Energy
- Replies: 7
- Views: 585
Re: Ionization Energy
Given that there are usually the same amount of electrons (e-) as protons (p+) in an element, if you remove one electron the proton will want more an e- more and thus there more energy is generated due to the pull of p+. However, once you remove two e- but maintain the same amount of p+, now you hav...
- Fri Oct 25, 2019 8:46 am
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: s, p, d, f orbitals
- Replies: 15
- Views: 833
Re: s, p, d, f orbitals
The 3D orbital is slightly higher in energy; visually, if you look at the periodic table, it can be seen that the 4s orbital comes before 3D.
- Fri Oct 25, 2019 8:39 am
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: What's the difference between subshell vs orbitals?
- Replies: 8
- Views: 685
Re: What's the difference between subshell vs orbitals?
Orbitals that have the same value of the principal quantum number n; n form a shell. “Orbitals within a shell are divided into subshells that have the same value of the angular quantum number l. Chemists describe the shell and subshell in which an orbital belongs with a two-character code such as 2p...
- Tue Oct 15, 2019 1:38 pm
- Forum: Properties of Light
- Topic: Variables and what they mean
- Replies: 9
- Views: 569
Re: Variables and what they mean
An easy way to remember that lambda is wavelength is to notice that it kind of looks like a wave in an ocean. V is for frequency and doesn’t look like a wave.
- Tue Oct 15, 2019 1:21 pm
- Forum: Properties of Light
- Topic: Homework
- Replies: 11
- Views: 578
Re: Homework
As mentioned above, as long as you do the five questions under the specified topic then you should be fine. The sections don’t matter as much to the TAs than it does for you to have sufficient practice for the exams.
- Tue Oct 15, 2019 1:16 pm
- Forum: Properties of Light
- Topic: What is Threshold Energy?
- Replies: 9
- Views: 781
Re: What is Threshold Energy?
As part of the photo electronic effect, light below a certain threshold frequency, no matter how intense, will not cause any electrons to be emitted. Light above the threshold frequency, even if it's not very intense, will always cause electrons to be emitted. This site might be resourceful: http://...
- Tue Oct 15, 2019 1:09 pm
- Forum: Properties of Light
- Topic: Wave Frequency
- Replies: 9
- Views: 552
Re: Wave Frequency
Maya Beal Dis 1E wrote:What is the relationship between the amplitude of a wave and the frequency? Or the relationship between amplitude and wavelength? What does amplitude tell us exactly?
I believe that amplitude tells you about the intensity of light. Hope this helps!
- Tue Oct 15, 2019 1:03 pm
- Forum: Properties of Light
- Topic: Angstrom
- Replies: 10
- Views: 562
Re: Angstrom
I typically convert everything to meters by default. However, unless the question specifies to convert measurements then I believe any SI unit should be fine as long as the answer is correct. As for angstroms, I wouldn’t worry about that measurement unless the question is relative to bond lengths or...
- Thu Oct 10, 2019 5:50 pm
- Forum: Balancing Chemical Reactions
- Topic: H.7 Catalysts [ENDORSED]
- Replies: 4
- Views: 482
Re: H.7 Catalysts [ENDORSED]
To add, catalysts typically affect the speed at which reactions occur rather than affecting equilibrium states of reactions.
- Thu Oct 10, 2019 5:48 pm
- Forum: Limiting Reactant Calculations
- Topic: L 35 Textbook Typo [ENDORSED]
- Replies: 4
- Views: 417
Re: L 35 Textbook Typo [ENDORSED]
Thanks for the heads up!
- Thu Oct 10, 2019 5:46 pm
- Forum: Limiting Reactant Calculations
- Topic: general questions
- Replies: 11
- Views: 1093
Re: general questions
I think of finding the limiting reactant as tryna make a sandwich. If you're making a peanut butter and jelly sandwich, you will need two slices of breads and one jelly jar, and one peanut butter jar. If one ingredient is limited, like a slice of bread is gone (out of 4) then you're limited to 1 san...
- Thu Oct 10, 2019 5:43 pm
- Forum: Administrative Questions and Class Announcements
- Topic: KAREN SUN 5-7PM WORKSHOP - DOWNLAOD WORKSHEETS HERE
- Replies: 53
- Views: 6604
Re: KAREN SUN 5-7PM WORKSHOP - DOWNLAOD WORKSHEETS HERE
Bita Ghanei 1F wrote:Will you be posting the worksheets and their answer keys weekly?
Thank you so much for making these!
I'd also like to know if you're planning on posting the worksheets weekly! Also, is it possible that you might have (or develop) a group chat to continue posting these sheets?
- Thu Oct 10, 2019 5:34 pm
- Forum: Accuracy, Precision, Mole, Other Definitions
- Topic: Test 1 [ENDORSED]
- Replies: 107
- Views: 46402
Re: Test 1 [ENDORSED]
Anthony Hatashita 4H wrote:Do we have to memorize equations or are we given a list of equations?
Aforementioned, no we do not. Hopefully this helps!
- Fri Oct 04, 2019 12:32 am
- Forum: Significant Figures
- Topic: How many sig figs when in decimals?
- Replies: 6
- Views: 469
Re: How many sig figs when in decimals?
Long story short, leading zeroes (or zeroes before numbers other than zero) are never significant and thus there is only one significant figure for numbers like "0.002" and such.
- Thu Oct 03, 2019 7:31 pm
- Forum: SI Units, Unit Conversions
- Topic: Dimensional Analysis Question
- Replies: 6
- Views: 376
Re: Dimensional Analysis Question
The other peers above are correct. The only additional information I could give is that dimensional analysis maintains organization in that you can visually see how measurements cancel each other out. It helps to find out the measurement of a solution especially when problems become more complex.
- Thu Oct 03, 2019 7:23 pm
- Forum: Significant Figures
- Topic: Determining Sig Fig's
- Replies: 5
- Views: 384
Re: Determining Sig Fig's
Here are the basic rules listed below:
1. Non-zero digits are always significant.
2. Any zeros between two significant digits are significant.
3. A final zero or trailing zeros in the decimal portion ONLY are significant.
Just remember that multiplication and addition are different processes.
1. Non-zero digits are always significant.
2. Any zeros between two significant digits are significant.
3. A final zero or trailing zeros in the decimal portion ONLY are significant.
Just remember that multiplication and addition are different processes.
- Thu Oct 03, 2019 7:17 pm
- Forum: Balancing Chemical Reactions
- Topic: Understanding how to get whole #s [ENDORSED]
- Replies: 18
- Views: 1481
Re: Understanding how to get whole #s [ENDORSED]
Depends on the problem and significant figures but if it were 3 SFs then there shouldn't be a need to round down.
- Thu Oct 03, 2019 7:09 pm
- Forum: Student Social/Study Group
- Topic: Study Group Fall 2019
- Replies: 32
- Views: 3005
Re: Study Group Fall 2019
Has someone made a group on groupme or FB? I'd like to join.
- Wed Oct 17, 2018 9:17 pm
- Forum: Photoelectric Effect
- Topic: Work Function: Increase in Energy
- Replies: 3
- Views: 544
Re: Work Function: Increase in Energy
Thank you for the clarification, Nada! :-)
- Wed Oct 17, 2018 8:54 pm
- Forum: Photoelectric Effect
- Topic: Work Function: Increase in Energy
- Replies: 3
- Views: 544
Work Function: Increase in Energy
So what does increasing the energy emitted from some light source do? Does it affect the intensity at which electrons are ejected or does it affect the number of electrons ejected? Does it do both?
- Wed Oct 17, 2018 8:51 pm
- Forum: Photoelectric Effect
- Topic: Work Function
- Replies: 16
- Views: 901
Re: Work Function
It depends - this question is fairly vague. Read the information thoroughly and figure out based off of the problem and the given information.
- Mon Oct 08, 2018 4:43 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 4374635
Re: Post All Chemistry Jokes Here
Are you the eleventh element of the periodic table because you're sodium fine B-)
- Mon Oct 08, 2018 4:38 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Advice from a Medical Student [ENDORSED]
- Replies: 297
- Views: 570063
Re: Advice from a Medical Student [ENDORSED]
Thank you!!
- Mon Oct 08, 2018 4:35 pm
- Forum: Photoelectric Effect
- Topic: Intensity of Photon
- Replies: 8
- Views: 1045
Re: Intensity of Photon
So what does increasing the energy emitted from some light source do? Does it affect the intensity at which electrons are ejected or does it affect the number of electrons ejected?
- Mon Oct 01, 2018 1:15 pm
- Forum: SI Units, Unit Conversions
- Topic: Week 1 Homework Assignment [ENDORSED]
- Replies: 16
- Views: 1346
Re: Week 1 Homework Assignment [ENDORSED]
From my knowledge, Destiny is correct - the homework is due Friday in class. You'll benefit from doing homework this week even if it is not assigned in the end because Lavelle put in his syllabus that he uses homework questions on exams as an incentive to study.
- Mon Oct 01, 2018 1:13 pm
- Forum: Balancing Chemical Reactions
- Topic: States of Matter
- Replies: 11
- Views: 2223
Re: States of Matter
An aqueous solution is when something is able to be dissolved by water. We need to include the state of matter when writing and balancing chemical reactions as it allows us to determine the solubility of some chemical reactions.
- Mon Oct 01, 2018 1:09 pm
- Forum: Significant Figures
- Topic: Significant Figures [ENDORSED]
- Replies: 6
- Views: 488
Re: Significant Figures [ENDORSED]
When finding measurements in general, we tend to approximate numbers (unless it's a definite measurement). The last digit of some measurement, in turn, becomes the least accurate as it's an approximation. Sig figs allow us to find more precise measurements of any given thing as it measures to the mo...