Chemistry

Dear chemists, I'm looking to buy a hot plate stirrer duo, but I'm not sure which brand or model would be suitable for me. I'm on a budget, but I also want something that's going to last for years to come. Any ideas? Thanks in advance, John

With over the counter white vinegar commonly consisting of 5% Acetic Acid, the rest water, would long term exposure to natural sunlight UV rays have any detrimental affect on the solution for use shifting average dirt in a household setting ?

Hey fellow scientists, I recently purchased a bulk order of Dutch double salted black licorice candies because I'm an idiot and thought I would actually like them given that I consider myself to have an explorative palate. I was very wrong. This stuff is nasty, and as it turns out, most of the world doesn't care for it either. I figured it would be a shame to let $12 go to waste just like that so I came up with the idea of trying to extract the ammonium chloride from all of the candies. Any chemists out there have any suggestions for an efficient way to go about this? If it's unrealistic I may just throw out the lot and cut my losses. Thanks in advance, Joh…

I live on a first-floor apartment right near the building entrance where the smell of smoke from tenants smoking near or at the entrance enters my apartment through the front window or door. I've made efforts to mitigate this issue including by sealing the window, using an air purifier and spraying Febreze, but none of these completely help and the latter two don't prevent the smell from entering in the first place. I'm considering making a suggestion to the board to have tenants smoke further away from the building. In the meantime I'd like to know: how much does the smell of smoke correlate with secondhand smoke in terms of harmful chemicals etc? I read there is no…

Disclaimer: If I ever try this, I will try it only on a teaspoon at a time, and ensure adequate time to be as certain as possible I am not getting severely intoxicated off the vapour. I do not recommend vaping alcohol in a general sense; this is more about the scent than the extent of drunkenness. There are some interesting smells from some alcoholic beverages, but leaning in the scent is only so strong. I've heard the boiling point of pure ethanol is 78.37 degrees centigrade... probably boiling point elevated when it's part of a solution, but still I presume from Clausius-Clapeyron that its vapour pressure increases more rapidly than that of water when heated…

Hi All, I’ve been thinking about this idea for a data logging capsule for a while and wanted to bounce it off someone and get some feedback etc. I’m really more of an electrical/embedded engineer not a chemist although I do enjoy really chemistry content on YouTube. To be completely transparent I would like to turn this into something comercial eventually. If this isn’t the right place to discuss product ideas apologies in advance. I had a look through the forum rules and there didn’t seem to be anything about it. I’m not trying to sell anything, I’m just looking for feedback on my idea which might be useful in some chemistry applications. Basically my…

How is the oxidation state in covalent compounds calculated ? For example, in H₂S, why does hydrogen have an oxidation state of +1 and sulphur has oxidation state of -2 as the electrons are being shared ? Can hydrogen have oxidation state of -1 and sulphur +2 (because the electrons are shared) ?

So when crude oil is refined, it is separated into different products. Some of it is used to make gasoline, some of it is used to make plastic, and I assume the rest of it us used for everything in between. And yet, I often hear of how gasoline is "not the best use" of oil and how plastic would be so much more reusable. But if different parts of the oil are used to make different products, how can that which was not channelled toward making gasoline be repurposed toward plastics?

In hydrogen, why cannot electrons enter an empty shell after the K shell is filled?

Dear community! I've just found a few contradictions in a topic I've never put much thought in. In order to calculate the thermodynamic activity, different formulas are being used. According to Wikipedia and common sense, these formulas should return the same value: According to IUPAC, the standard values for concentration and molality are 1 mole/l and 1 mole/kg respectively. Thus, this relation is only possible if the activity coefficients for x,b,c and so on are different. Consider a simple example, 0.5 mole of a substance J dissolved in 1 l of water (~55 mole): As you can see, the values of the activity coefficients depend on whic…

It looks like hot water freezes faster then cold water.https://en.wikipedia.org/wiki/Mpemba_effect#Suggested_explanations Is it possible that due to the heat, watermolecules have more energy to form the hydrogen bonds in ice?

Is the solvation of salt (NaCl) in water a chemical reaction?

HI Can anyone tell me what would melt Perspex, was told Methylene Chloride would ! , so am just checking on here if that would or what other chemical will . cheers Spike

Once again, California is on fire. Apart from the threats to property and safety, that's a lot of chemical energy in nature that is being squandered on a fire that isn't occurring underneath a boiler to boil water for food or electricity. I wonder, now... if society were to hire more of the recently-unemployed as loggers, and have them cut down enough trees that the wood could be burned in lieu of fossil fuels, (and/or be converted to paper and used as such before being burned) would this double as a way to make forest fires less severe, by the fact that there are fewer trees available, per square kilometre, to catch fire in the first place?

Theory: Water originates from very cold area’s in the universe, as in nebulae, and from cold objects far away from their star. And maybe also from very cold polar regions on (dwarf-)planets as Mars and Pluto? Or not?

1. How many types of man-made leather (for clothing) ? 2. Do they often have fairly the same composition but only a slight variation? Or could they vary a lot? 3. I have been hearing that man-made or faux leather could be hazardous to health. 4. Are the risks due to the chemical itself or other chemicals / addictives used in the manufacturing process? 5. Do the risks naturally exist because of the nature of the chemicals itself or do they only exist if it's manufactured by inappropriate or illegal process? 6. Is there any sign that we can determine if it's a "risky" leather? Many people said that to check if it has strong and unpleasant smell. Is it true?…

I heard, molecules only at the surface of the liquid evaporate. But do the molecules below the surface of the liquid evaporate? Suppose we heat a container containing a liquid from the bottom. So molecules at the bottom of the container will have higher kinetic energy than the molecules on the surface. How will the molecules on the bottom escape as vapours?

The glue in this bag and the glue on this label contain what chemical composition? these two glues dry evaporate and corrode electronics that are inside that bag and inside the box where that bag is located?

I am wondering what is released in an ammonium nitrate explosion. Ammonium Nitrate = NH4NO3

Ok so this might sound really dumb. But I was wondering if anyone can help me out here. I got this caulk sealant on the pavement and I was trying to remove it. I used some gasoline to try to remove it. It worked but it got me thinking about my long term heal. I have some pictures of the sds below, this stuff seems pretty bad to inhale, but my main question would be, by adding the gasoline would this cause it to become more toxic? I was outside when doing this.

The Periodic Table of Elements is one of the greatest discoveries and developments in the history of science and it remains the most important tool in all of chemistry for making predictions about the behavior of matter. Because the Periodic Table is so powerful, what I am going to say isn't going to be popular or easy for people to accept. It will be far easier to dismiss or delete this post, even though everything that I am going to say is easily verified. The discovery of the Periodic Law by Russian Chemist Dmitri Mendeleev in 1869 launched the academic and scientific communities of the world from studying Alchemy, to Chemistry and Quantum Mechanics virtually over nig…

On my periodic table, there are multiple ionic charges listed for some elements. I assume this is because there are multiple possible ions. However, I have a homework question that asks for the ionic charge of an atom, and does not give a number of electrons. For example, a Sulfur ion: On my periodic table, it lists the charges 6, + or - 2, and 4. Are they all equally possible, or is there a "right" answer? If the latter, how do I know?Thanks!

When downplaying climate change, people often invoke the fact that CO2 is given off not just by fossil fuels but by breathing as well. When celebrating others' deaths, people like to say "well, [insert person whose death is being celebrated here] was a waste of oxygen while they were alive anyway." I don't mean to imply the above come from the same people; in fact, I have no specific example in mind of anyone I can confirm for a fact has definitively said both. My point is that people seem to be under the impression that the consumption of oxygen to replace with carbon dioxide due also to respiration, rather than just combustion, is sig…

In my early teen years, I loved playing with vinegar and baking soda at home during the summer months, but I hated chemistry labs at school. The crowded, hectic, noisy, structured, time-constrained stressful environment wasn't exactly as charming as a bottle popping in my backyard in the warm summer sun. And now, the next generation of students is facing a situation where school isn't just stressful, but could be a literal threat to life and limb. We are told the teacher must supervise a student in person when they're carrying out chemistry labs; that doing these at home at a distance would be reckless endangerment. Well, sending kids to school dur…

Hello, I am not knowledgeable about chemistry whatsoever, but I run a company preserving bouquets out of my home and I have some questions about the silica that I use to dry flowers. I use a brand called Activa silica gel which has a fine grain sand texture. I pour the silica over flowers in order to absorb the moisture out, and then pour it off of the flowers and bake the silica in the oven again to dry out, or reactivate the silica. It's well known that flowers can have up to a dozen different pesticides by the time they make it to the shelf. I currently work with a face mask because it kind of freaks me out to breath in the silica dust that gets kicks up with …