/sci/ - Science & Math

>>15596038
Intradasting explanation.

A random question that's bugged me for many years.
In the equilibrium constant of any aqueous solution, if water is involved, the activity of water is always treated as 1. This is by definition. However, it is the case that reactants or products within an aqueous solution can exceed a concentration/activity of 1. That doesn't logically make sense to me - the solvent surrounds all the molecules of reagent and product and it just doesn't seem right that the activity of a reagent can be higher than that of the solvent when both are involved in the reaction.

Say, for instance, the reaction of a 2M solution of Manganese (II) with sodium hypochlorite in hydroxide to yield sodium permanganate, chloride and water. If we remove the spectator ions, the conventional equilibrium constant approximating the activity to the concentration will be of the form K=[Cl-]^5[H2O]^3[MnO4-]^2/[ClO-]^5[OH-]^6[Mn2+]^2 (If i have not been careless)
Apologies for the formatting. The point is that we will conventionally take the activity of water as 1 and then remove it from the equation. But here, this implies that water is less active than Mn2+, the latter of which is orders of magnitudes more sparse within the reaction mixture. It thus makes little intuitive sense why water would be less active than Mn2+ in such a solution. The concentration of H2O is always 55.6 (iirc), and this factor is always ignored. Why?

I did first consider the issue to lie with the approximation of activity to concentration. However, activity coefficients still remain high in concentrations of solutions upwards of 10 molar. Meanwhile, water, despite surrounding literally all the reagent molecules, is arbitrarily capped at 1.

Stackexchange was pretty useless in answering this question. As such I come to /sci/ without much hope, considering this is fucking /sci/. But you guys did manage to solve some difficult math shit, I think some basic pedagogical equilibria chemistry cannot be especially difficult.

Thank you.

We saw a lot of shit in the past years, above everything political drama and people inserting their personal biases in everything they touch, muh pro-anti-science etc. etc.

So let's restart from the very basics, how do i perform a scientific investigation? describe the method and the steps as if i'm an ignorant fuck ( i actually am).

Can life exist as germanium-based? Or does that go too far?

>Sonoluminescence is the emission of light from imploding bubbles in a liquid when excited by sound.

i dont get it how do they work?

I have some question, docs, it's sport medicine:
does prolonged high intensity anaerobic exercise, that lead to lactate accumulation, cause acidemia?
or can the body compensate easily? how does it compensate?
could a prolonged state of high lactates in the blood be harmful?

If it scrubs today, when would the next launch date be? Do you need any window for suborbital launch other than good weather?

Spent the whole weekend learning derivatives and my brain is complete mush from burnout. Feels good.

Different question: What is it about the mirror that makes it reflect waves the way it does?
What is the difference between a mirror and a wall? Both of them have their electrons agitated when hit with light waves and then release weaker waves into my retina. What makes the mirror so special that it can reflect things perfectly?
Does it just not absorb any of the colors and reflect basically everything while the wall absorbs most of the spectrum? But that would mean i would still be able to see red things behind me if i looked at a red wall.

>>15311296
When Katie's black hole pic was all over the news I took that image and overlaid it over an image I had of a woman bending over and spreading herself open and the holes matched up perfectly - size, shape, deep black void - everything. It was spooky. I still have it, I think.

When i put the poopoo on the peepee, why the poopoo always sinks to the bottom?

Does heart rate increase when you inhale just to maximize oxygen efficiency? Or is it something stupid?

>w-wwe-were-I'm g-gonna

Why don't we hack cancer and use it grow bigger brains whenever we want in adult life?

>integrating over a discontinuity

>>14873838
>Eplrooka
>Reorrobla
I'll keep a lookout for these countries, might be some interesting stamps

Are there any applications of PCR testing outside of Covid-19 or viruses in general? It would seem to be a good way to diagnose genetic diseases, mutations or tumors and there is scientific journals on the subject, but I am unsure if it is actually used in those application in practice, especially since most information on PCR is related to Covid-19.

>>14799112
Autism is typically thought of as an impairment with the subject's theory of mind.
Your "theory of mind" is the way you're able to imagine things from a perspective other than your own.
There's a kind of experiment called a false-belief test where you give the subject information that a hypothetical third party wouldn't know, and then you ask them what that hypothetical third party would say or do in the same situation. If your subject doesn't have a working theory of mind, they will respond in ways that depend on their own personal knowledge without correctly factoring in that the third party doesn't know what they know.
e.g. There's the box test, where you might put crayons inside an empty band-aid container, close the container and then ask the subject what's in it. The subject (regardless of theory of mind) will probably answer "band-aids." Then you reveal to them the contents are crayons instead. And then after doing that, you ask them what another child who isn't in the room would say if someone asked them what's in that container.
If the subject is not autistic and is old enough to have developed a theory of mind, then their answer will be "band-aids," because they will have successfully imagined the situation from the other child's point of view.
For a very young child or an autistic subject though, they will answer "crayons," because they can't properly imagine the situation from another person's perspective and will instead use their own personal knowledge to decide what another person would say.
Not having a working theory of mind has implications for a lot of routine social processes, including the recognition of and assignment of emotions to facial expressions. If you can't imagine things from a perspective other than your own then you also can't imagine what emotions a person other than yourself is experiencing.

>>14749814
well you see if we pee the poo we can actually get the poo instantly into pee (full flow stage pee), thus making the isp near infinite without autogenous poo pressurisation limiting our mass fraction
This is simply why we do science

A cup of steel is equal to a cup of feathers

...999 = -1

Proof: ...999 + 1 = ...000 = 0

The magnet pulls the metal part, so you would think the car moves forward. But the reason why it does not is because the metal also pulls the magnet, and this pulling force of the metal part has to be applied to something to prevent the magnet and the metal from colliding into each other. And because the magnet is attached to the car, the force is applied to the car in the opposite direction. The car is being pushed in two opposite directions with the same force so the car won't move.

how do we know she is studying and not just browsing the web and sleeping while pretending to read a book