Chemistry Definition and 993 Threads

https://www.reuters.com/article/us-mexico-molina/mexican-nobel-laureate-molina-ozone-layer-prophet-dies-at-77-idUSKBN26T03Q Molina shared the 1995 Nobel Prize in Chemistry with Paul Crutzen and F Sherwood Rowland "for their work in atmospheric chemistry, particularly concerning the formation...

https://www.nobelprize.org/prizes/chemistry/2020/summary/

Hello, A rock salt (NaCl), ice, and water mixture is used to cool milk and cream to make homemade ice cream. How many grams of rock salt must be added to water to lower the freezing point 14.7°C? (Assume that there is 1 kg of water.) How to answer this question...

I'm supposed to make a project on "Green Chemistry".so if you guys have any suggestions for a good book?

Ok so I am building a fume hood What materials are the most resistant to chemicals that are also cheap? also what cfm fan can I use to suck out the air? (asking for someone knowlageable) cats

8th-grade science student. I want to major in 9th-grade chemistry. I currently live in Pakistan. Perpetually interested and always ready for books, cats, knowledge, and cats

Hello, so first of all I want to clarify that english is not my first lenguage, so I'm really sorry for possible future errors. Second, this is a problem from my physical chemistry class, and I'm not sure where it fits better, if here or in the physics homework help, I'm sorry :( So, I don't...

For organic chemistry, what is important to memorize when I am reading a textbook? Should I memorize the structures and names of different organic compounds when they are described as examples? Or is it more important to memorize the organic reactions? Also, does anyone have any tips on how to...

Hi, 10.0 dm³ of sulfur dioxide is reacted with 6.0 dm³ of oxygen according to equation below. 2SO₂(g) + O₂ → 2SO₃(g) What volume of sulfur trioxide in dm³ is formed? If any member knows the correct answer to this question may answer to this question. Please answer with your...

I took chemistry in high school & college 50 years ago. I don't remember how to do chemistry math? If someone knows the answer to my question it will be much easier than for me to figure it out BUT I would like to know how it is done I love technology. I took engineering in college. vinegar...

Is my work and the answer correct? If not, how should I approach this problem? Thank you!

I want to know how a lithium ion rechargeable cell works with very basics details. I don't need a simple describtion like most of the websites and videos. I need a resource that explain the chemistry and physics of a Li ion cell from very basics of knowledge. Could you please introduce such a...

My name is Nwanaga Chikamso Placid. Am a Nigerian. I love research and have interest to know and learn all the time. Hope am welcome.?

I am looking for information on multiple things but, currently, looking for how fast each element's nucleus spins/moves in its "designated space". Does the nucleus itself rotate? If so, how fast? And is it different for different element's? (I'm not sure I'm doing this correctly. I just need to...

As with probably a lot of pure science undergrads, my dream goal is to become a researcher, academia or industry. As far as I know at the moment, I'm interested in the area of research that straddles physics and chemistry, and I'm not sure which one I should major in. Should I major in chemistry...

Hi , I 'd like to make a master degree but am not sure which department should I join to meet my goals that I will tell you about shortly , let's begin by my background first, Background : I have a bachelor in computer and communications engineering , during my study I had basic Electronics...

It is desired to remove the molecular hydrogen present in a flask. What will be better to introduce, ##Cl_2## or ##Br_2##? Why? ##2 HCl <-> H_2 + Cl_2## (1) ##k = 3,2.10^{-14}## ##H_2 + Br_2 <->2 HBr## (2) ##k = 2.10^9## I thought about turning equation (1) to make the...

My attempt- 1)The given ligand forms chelate rings,so it should be a chelating complex. 2)It has no plane of symmetry (P.O.S),so it is optically active(octahedral complex) and should have 2 optically active isomers. 3)They are not polymerisation isomers because they have different emperical...

I need to brush up on some Chemistry over Summer, and I wondered if anyone knew of some problem books pitched at a similar level to Irodov's problem book for Physics, or things like IChO questions. Preferably it would include all of physical, inorganic and organic, to some degree. I get various...

It will try to produce a neutral atom but it depends on the amount of energy that electron is shot at the atom, if it is great enough energy for ionization it will produce cation, If it is not enough for ionization it will make a neutral atom or anion, I think.

I think that an electron adds up in the valance shell of an atom because an atom tends to achieve the nearest noble gas configuration. But I don't understand how and why electron enters the valance shell. Energy is released when an electron adds up in the valance shell. But why is energy...

All our bitumin roads decay over time by ultraviolet light and slightly acid water. What is the chemistry of this? There is a lot of stuff on the internet about change in physical degeneration but not chemical degeneration? What is a suitable reference?

Wiki said "Arnold Sommerfeld calculated that, for a 1s orbital electron of a hydrogen atom with an orbiting radius of 0.0529 nm, α ≈ 1/137. That is to say, the fine-structure constant shows the electron traveling at nearly 1/137 the speed of light.[9] One can extend this to a larger element with...

A new article in Phys.org discusses a paper recently published in "Science Advances". Although I am unable to find that article. Professor Webb at USNW reports that there appears to be a gradient across the universe over which fine structure constant varies. (Wow!)

Summary:: How to do chemistry labs and demonstrations for online education. I am teaching two lab sessions one on general chemistry, one on organic chemistry. Now th we are going “online” I need a lot of help. Do you have videos showing labs?

I’m a freshman in undergrad and I currently attend the University of Illinois at Chicago. I major in electrical engineering but I have an extremely strong interest in physics, chemistry, and materials science. UIC doesn’t have a materials science program, but George Crabtree, a highly cited...

I've tried both c1v1 and unitary method but couldn't solve

Hey all, I've come here to seek out some help creating the perfect espresso brewing water. I've done some research, and I think I've reduced it down to a chemistry problem. I'll be starting with distilled water and adding minerals, some 'hardness' and an 'alkalinity buffer.'First, here's the...

The question says: A solution of highly acidic HA is given, with a molarity of 1M. Is it true that [A-]>[H3O+] or not? I simply don't understand why the hydronium is mentioned and i don't know how to find the molarity of these two individually.

Summary: At some point, there has to be a point where the "goo' (as described by "Q") becomes us, what is that transition point? What made not life, life? <moved to general discussion> I have been looking around the internet for an answer to this question. The difference between "life" and "not...

I am having troubles with a question I have to do for my chem pre-lab. The question is: The following intercept and slope were obtained for a Beer’s Law plot of Absorbance versus concentration (mg Fe2+/L). Slope = 0.2200 L/mg Fe2+ Intercept = 0.004 Calculate the percent (by mass) of iron in the...

https://www.nobelprize.org/prizes/chemistry/2019/summary/

Hello guys. I really try to understand the problem, can you please help.

Okay So our Chemistry Professor gave us the answer as the following IO2F2 has a larger bond length than IOF3 The reason being is once you draw the structures of the compounds IO2F2 has more number of double bonds that the later hence it shall have more p charecter than IOF3...hence it will...

Hello All, I have attached my questions with pictures in attached photos. Look at screen shot 46 first then screen shot 47. I am having trouble ranking acidic protons. In my Organic book it has the order of: 1)Charge 2)Atom Type 3)Hybridization 4)Resonance 5)Induction Things I know: S is able...

Summary: Chemistry undergrad attempting to go to graduate school in physics. Would appreciate advice. Hello, I am in my fourth of five years at a solid school studying chemistry. I changed my major at the start of my third year from economics to chemistry after being inspired by a course in...

Here is my attempt at a solution. The thing I am not sure about is the final result of the Shrodinger equation and the n-values that are offered? Did I make a math mistake? Thank you so much for reading through this!

I'm getting 2119.36 for the concentration of mg/cubic meter of this substance...it just feels wrong though. Steps I followed: First, I figured out how many grams of the substance there were using the density formula, then saw how many were present per cubic meter after calculating the volume...

Hi, I’m an undergraduate student interested in cognitive processes. I’m about to ask a very interdisciplinary question, and so hopefully I can find a physicists that can take on the challenge. What is the fundamental reason behind why modern electronic computers (transistor computers) are...

I think it is 1:10 but I am not sure the meaning of PKa -1, can someone explain it please.

I am working on some simulations to determine pressures for extremely high-pressure combustion events. The temperatures in these events can range anywhere from 3000 K to 6000 K. In order to do this I need to find valuers for specific heats of gases at these temp ranges as I know they vary to a...

I'm master physics student looking for books in physical chemistry for stuff like born Oppenheimer Approximation and more. Most books give hand-waving proofs and I'm looking for a book which is more rigorous. Thanks

Problem Statement: A sample of excited atoms lies 3.031×10^−19 J above the ground state. What is the emission wavelength of these atoms? Relevant Equations: E=hc/λ λ=hc/E I'm stuck on the first part. i.e; something / 3.031x10^-19J

Hello, I looked into lists of subjects/courses for Physics Major, and I surprised that Introductory Chemistry is in the list, as mandatory course. I suspect that Molecule and Solids and Nuclear Physics chapter have to do with chemistry Why is it mandatory to take Introductory Chemistry course...

Hello! My name is Fabrizio, I'm a high school student doing some research on the atmosphere. Right now, I'm trying to figure out how much matter escapes into space via Jean's Escape. I've found several formulas, all of which require me to know what the amount of particles per m3 of a certain...

Summary: Thread for discussing the USNCO and how to do well on it. More specifically, tips for doing well on the national round and making the study camp are welcome. Anyone with experience with the olympiad is welcome to post, especially previous study camp qualifiers and honors/high honors...

Hello! There is a problem to write chemical reactions that goes with substances if they are not stored properly. For example theophylline should be saved from light and though I am trying to find its’ reaction with hv(light) but failed. Please help with some good reference Many thanks in advance

I think that the double bond would be broken in some way but what happens to the two bromines? do they remain in the ring? (or does HBr forms? is it possible?)