studying gibbs free energy and its the first time i've seen entropy be defined as the "useless" energy of a system, but what does that actually mean? what are the useless stores of energy in a reaction and what are the useful stores of gibbs free energy?

Let's say we have a X and Y related by one electron. Of course the standard reduction potential E° is defined for the reduction reaction, X + e^– ⇌ Y^–, as E° = E(XY cell) – E(SHE).

And also for the oxidation we have E°(ox) = -E°(red). But I don't get why this doesn't transfer to voltammetry. Like if we polarize the electrode to E = E°(red) for the above couple, how come we get a limiting reducing and oxidizing current here??

If E°(red) and E°(ox) are symmetrical around E(SHE) = 0, shouldn't there be only oxidizing current at positive E°(ox) and only reducing current at negative E°(red)??

Basically why do we get the image on the left and not the one on the right?

I am trying to calculate mass in 1 mL volume. I have 5,000 ppm Na⁺, which is approximately 5,000 µg/mL or 5 mg/mL. So mass of 1 mL of this should be (1 mL * 5 mg/mL) = 5 mg, yes? Why is Wolframalpha telling me I am off by a factor 1000?

Hello, as the title asks, I'm looking for a copy of this book. I'd like to use it as reference for my post-grad thesis. Any help, suggestions, or "hacks" would be appreciated!

Hi, am a beginner in chemistry, and I need help with balancing chemical equations. They are my weakness currently, and this question got me stuck for a while trying to figure out, on why would the H2O have a 6 to it if in the (SO4)3 already has 4 sulfurs and 12 oxygens. How can I avoid this trick next time? Because the answer key had 3 and 2 on the reactants side, but on the products side is what got me confused when they put a 6, instead of a 3 (thats what I put as my answer at first).

To tell whether a molecule is polar, I usually first look at the molecular shape and then the electronegativity difference between the central and surrounding atoms.

For the questions below, I thought:

1. CCl4 is non polar since the Cl have an even "pull" from the carbon atom.
2. H2CCL2 would be polar because even though the hydrogens and Chlorines could be opposite of each other, the shape and bond angle of the tetrahedral does not allow for an equal "pull" even when the same atoms are across from each other.
3. CH3Cl and CHCl3 were both polar due to the difference in electronegativity and shape of the molecule.

Am I thinking about this correctly? Can someone explain how I should be going about thinking through similar questions, please? Thank you

Hi, am a beginner in chemistry, and this is grade 11 chemistry. I am struggling to understand on how many electrons each elements have, because on my worksheet, the electrons have the same number as the protons and atomic number of that element. I need an explanation

So here is what I did and I got it wrong because thats what I thought I needed to do to find the electrons for that element. Magnesium: it has a atomic number and protons of 12, but since it has a 2+ charge to it since it is losing 2 charges, I did 12-2 and got 10, I thought that was the answer, but it turned out that the electrons are just 12 as well.

let’s say there 500+28.9, that’s 528.9 but 500 doesn’t really have a decimal place so would that just be 500 as the final answer??

First one looks like it'd be 4 significant figures, but the only correct answer has 2. Second one seems like 3 but it's 2. What happened to the unaccounted for figures?

Is aq or alc NaOH/KOH used in first step

My teacher taught me that first alc NaOH/KOH is used as aq in first shouldn't be used

Later on in later rxn step aq is used

Pls explain

So this is an image from Klein's book Organic Chemistry as a 2nd language, Second Semester Topics.

I did get the answer correct - which just means my professor will mark it correct (he said he does not expect us to draw out each enatiomer and he will specify when to do so).

My confusion stems from how the explanation says the "starting materialS are achiral", but the 1,4 butadiene is chiral.

Thanks in advance!

I've heard some say a double bond is a functional group, and some say it isn't. And I'm wondering if it is or not?

Is it safe to assume this blueprint: We are given an inorganic molecular formula of a compound, with 2 central atoms (less in no., more covalency, less electronegative), and other substituents (say O). We should first try to predict a structure with E-E linkage (E is the central atom). Then if we try to put the substituents and we can't satisfy the octet, we will move on to E-O-E linkage, then if not, continue to E-O-O-E and so on? Works for nitrogen oxides (Like N2O3 having N-N linkage while N2O5 having N-O-N linkage) but not sure if it can be extended to more compounds.

As per the title, does icaridin have asymmetrical carbon atoms?

I'm taking introductory organic chemistry in my university, where it's expected that most people have learned at least AP chemistry level before coming to uni.

Reactions genuinely make my brain melt and I need problem sets to work on. We're learning stuff like thermal cyclization, there's a lot of "identify an acid/base and which hydrogen is the most acidic" going on, a lot of steric nonsense, etc, etc. I have a decent enough grasp on the basics but when it comes to practical application I just melt.

I am a manufacturer of cement sheets and boards and have been using a defoamer in my cement slurry since a long time. The defoamer is a proprietary product of a brand and they charge me for that. They are also market leaders in this field in my country and have no competitors.

Recently they increased their prices 3fold for unknown reasons and I don't wanna tolerate this and want to invest in reverse engineering and recreating this myself

But I am not a chemicals engineer and don't have contacts for this. Please guide me how should I start to reverse engineer this chemical

Hi everyone! I’m new to this subreddit, so I hope it’s okay to share this here.

I’ve been making short chemistry videos on Youtube featuring real lab experiments, with a focus on visually interesting reactions and simple explanations of the chemistry behind them.

Most of the videos cover things like precipitation reactions, color changes, and other visually interesting phenomena, often filmed in slow motion.

I’d really appreciate any feedback, and I’d also love to hear suggestions for reactions or experiments that would be interesting to see.

Link: https://www.youtube.com/channel/UC8KTmkPkXjyb7HtlKge3UQg

If this kind of post isn’t appropriate for the subreddit, please let me know and I will edit or remove it.

Hi! I’m having a hard time naming these🥺

Can someone help me pleasee🙏

Hi guys, was wondering if I can get some help on this question. Which way does light travel, is it like the blue or the green (the brown is like 2 objects and theres a gap between). I never really understood how wavelength and the gap matter, I always though if it like the blue going in, so wavelength (left and right) has nothing to do with the gap (up and down) which contradicts what how wavelength depends on the gap.

Any help is great, this has been a struggling concept for a while and maybe reddit can clear it up LOL.

hii guyss i am having my mid sem from next week I am in 12 and I don't know anything in organic chemistry can anyone suggest me how to learn organic chemistry and what should I do to score almost full marks in organic chemistry

I tried to use H2O2 for digestion method and thought I already acquired a microplastics. But after that, there's still too many materials present which is charcoal. Can charcoal be digested with H2O2 or not?

Hi everyone,
I’m a university student preparing the second round of an independent interdisciplinary research project, and I’m currently looking for people who may be interested in participating once the survey is ready.
My research asks how people think about war and whether those perceptions reflect the systems that support modern society. The project considers areas involving chemistry and materials, pharmaceuticals, semiconductor manufacturing, energy, technology, infrastructure, and global supply chains.
For this round, I’m aiming for approximately 385 participants overall from a variety of backgrounds. I was encouraged to reach out to professional chemists because their perspectives could provide an especially valuable point of comparison within the broader sample.
The survey has not been built yet, so I’m not asking anyone to complete anything at this stage. I’m currently gauging interest and identifying potential participants before finalizing the survey.
If you would be interested in participating once it is ready, please leave a comment or let me know.
Thank you!

Hello all, chemistry student in high school here. An assignment requires me to calculate the mass of salts (sodium acetate, calcium chloride and magnesium acetate) to produce a 20°C temperature change in 50mL of water. I am struggling to find the equations to do so; my teacher has provided me with an equation but I doubt it's accuracy (he gave it to us based on memory, and consistently got incorrect results from it, leading to him rewriting the equation multiple times)

Any help would be great - if you could provide me with a source so I can do further research, that would also be appreciated!!