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#5681 - totalnotito
Reply 0
(08/26/2016) [-]
Is it possible to synthesize sodium hydroxide by the electrolysis of sodium hydrogencarbonate solution using carbon electrodes. We're talking distilled water and sodium hydrogencarbonate, so there are no "third" reactions present

NaHCO3 + H2O + e- ---> NaOH + H2 + CO2

#5684 to #5681 - mublerking
Reply 0
(08/26/2016) [-]
I'm not sure about that but I know you can do it significantly more simply with hydrolysis and regular table salt (NaCl) supersaturated into water. Just look up a video on making Lye from table salt, there should be plenty.


NaCl+H2O--->Na(+)+Cl(-)+H2O-- electrolysis-->Na(+)+Cl(-)+OH(-)+H(+)--->NaOH+HCl

so if you do it in a divided cell, one cell will become hydrochloric acid and the other will become sodium hydroxide.
#5687 to #5684 - totalnotito
Reply 0
(08/27/2016) [-]
I just tried the divided-cell electrolysis. I wasn't aware that it produced SO MUCH chlorine. My house now smells like a WW1 battle field and my lungs sting. But it worked.


I turned it off for safety, but god damn...
#5686 to #5684 - totalnotito
Reply 0
(08/26/2016) [-]
Wait it just got into my head, you already said double-cell. In that case yes, I can see it working
#5685 to #5684 - totalnotito
Reply 0
(08/26/2016) [-]
Wouldn't the acid and the base neutralize eachother? Maybe if you separate them somehow...

I'll look for videos, but I was just wondering if it was possible
#5669 - kunchuma
Reply 0
(08/24/2016) [-]
is it possible to not be able to get addicted to smoke?
#5678 to #5669 - platinumaltaria ONLINE
Reply 0
(08/25/2016) [-]
Hypothetically yes.
#5668 - kunchuma
Reply +1
(08/24/2016) [-]
why do animals explode when they are microwaved? or is that just things that happen in movie?
#5673 to #5668 - mublerking
Reply 0
(08/24/2016) [-]
That's not something that really happens. If it could happen, it would be caused by heating the interior more than the exterior thereby causing a pressure to build up and the animal to expand. The microwave doesn't emit sufficient energy to actually do that. It heats things by exciting the water molecules inside it via radiation, all molecules have a resonance frequency usually related to bond length and the frequency with which their bonds rotate and contract/expand. (the microwaves frequency is about 2.45Ghz which isn't water's exact resonance it is slightly off, this is because any higher and the waves would barely penetrate the surface because the surface water would absorb it all, any lower and the waves would penetrate much deeper but wouldn't really be able to heat it.) So if we increased the energy to one that was sufficient to cause the pressure build up it would actually only heat the outside first and that wouldn't cause it to explode.
#5667 - caet
Reply 0
(08/24/2016) [-]
Evolutionary question:
Why do we lose skin pigmentation in regions with less sunlight?
I mean I know less melanin is needed because there's less need for protection.
But why do we actually lose it instead of keeping it 'just in case'? is there actually something detrimental about having too much pigmentation when it isn't needed?
#5679 to #5667 - platinumaltaria ONLINE
Reply 0
(08/25/2016) [-]
Pale skin, more UV ,dark skin, less UV
North/south, less sun, equator, more sun
#5680 to #5679 - caet
Reply 0
(08/25/2016) [-]
It was already answered
#5670 to #5667 - Fgner ONLINE
Reply 0
(08/24/2016) [-]
Less sunlight, but our needs for vitamin D remains. The body uses sunlight in a few ways and the darker skin was detrimental to our ability to do so.
#5671 to #5670 - caet
Reply 0
(08/24/2016) [-]
oh so less sunlight means lighter skin so we're able to extract more from less...
I guess that's also why we're also more proned to skin cancer when we're out in the sun in regions we weren't made for
#5674 to #5671 - Fgner ONLINE
Reply 0
(08/24/2016) [-]
Bingo, friend. It's also why darker skin folk have deficiencies when they move to mild sunlight regions, as their skin is too effective at protecting them. And when a fair skinned person goes out in the sun, the lack of melanin means less protection against UV radiation which, as most radiation does, damages DNA and increases the likelihood of skin cancer.

Light skin folks have an advantage here, though, since we actually evolved our trait as an adaptation to changing environments. When exposed to excess sunlight, we produce more melanin closer to the surface of our skin, giving us a dark tan and the protection we need in proportion to how much we need it. Dark skin really can't get whiter. So a darker skinned person has trouble up north, but a lighter skinned person will have much less trouble coming south.
#5675 to #5674 - caet
Reply +1
(08/24/2016) [-]
So our skin developed a mechanic after losing pigmentation as a 'well they moved once, they may move back' fallback plan
that's bretty cool
#5676 to #5675 - Fgner ONLINE
Reply 0
(08/24/2016) [-]
Damn straight it's cool.

And since I did mention whites being more evolved, I want to clarify and say that the only evidence we've found for intelligence shows that there's no real intelligence gap between the races - it's almost entirely cultural. Any racial divide falls within error margins and is immeasurable. I'd hate to justify any kind of racism from that comment.
#5677 to #5676 - caet
Reply 0
(08/24/2016) [-]
It's literally science. It's not racist to acknowledge the facts. lol
#5666 - alpacalypse ONLINE
Reply 0
(08/22/2016) [-]
what is your favorite animal
#5672 to #5666 - caet
Reply 0
(08/24/2016) [-]
im gonna go with cheetah cause that was my favorite as a kid
#5665 - minutes ONLINE
Reply 0
(08/22/2016) [-]
I don't know if this is the right place to ask.

I want to learn multivariate statistics. I did a 9 credits statistics course in university once which I passed with a good grade and want to continue learning. Sadly, multivariate stats courses only get offered in masters degree courses on my uni. The thing is, I want to do a statistics master later on and it would be better if I knew this stuff already before I start it.
Does anyone of you have tips on how to teach yourself multivariate stats? Any textbook recommendations or whatever else would be apreciated.
#5664 - mublerking
0
has deleted their comment [-]
#5661 - meierme
Reply 0
(08/20/2016) [-]
TLR lots of radiation exposure and wondering how to test to compare with normal amounts. Cant afford a doctor, curious if there's an over the counter way.

I have been thinking about my radiation levels lately. In the past 5 years I have had a barium swallow (exposed for 4 min), upper GI scan, lower GI scan, CT scan for multiple fractures in my shoulder, a couple standard X-rays, and a total of 13 CT scans after my appendix burst (I went septic). Of those 13 about half were really quick I had a pooling of infectious fluid in the center of my pelvis, so they had to drive a 1/4 in tube through my butt cheek to drain it. During the proceed they used the CT scanner to make sure it was going in the right direction. Every now and then stopping to do a quick check. That thing was in there for another 2 weeks after I was discharged. . While I was still in the hospital a cancer specialist came to visit me and said I have had way too much radiation exposure. She was pretty vague on everything else but I am curious as to when I should be expecting cancer?
#5662 to #5661 - mublerking
Reply 0
(08/20/2016) [-]
To answer your question directly, blood work is the obvious option (as it is the most accurate representation) but as you said over the counter. You could get a dosimeter, they can be fairly cheap and ordered online (cheap ones are like 10/15$). That would give you a vague estimate of your radiation exposure. Although this is the vaguest of vague estimates as it doesn't tell you how much your organs have absorbed. There really isn't any kind of accurate test for that, even the numbers doctors report are just kinda "well you've had this done and that done and it'll give you about this much so here's how much"

Although if you're freaking out about it, you probably shouldn't worry. X-rays only give 1.5mSv of radiation, and CT scans (45-60 minutes, I'm not sure how long you were) give an effective dose of 3.3-10mSv. <3mSv is low, 3-20mSv is moderate, >20mSv is high. From the sound of it though you kind of needed those tests, so think about it like this: you couldn't really have done much to avoid them.

Source: trust me I do physics in all seriousness and in the event you haven't seen any of my other comments, I'm a particle physicist.
#5663 to #5662 - meierme
Reply 0
(08/20/2016) [-]
Not really freaking out about it, I just wanted to know if I'm a walking radioactive ghoul. honestly getting told I had cancer would be a relief
#5658 - shaunata
Reply +2
(08/18/2016) [-]
Is the reason why plants don't really die from cancer like animals do is because, their cell walls prevent the malignant cells from spreading and matasticizing?
#5659 to #5658 - mublerking
Reply +2
(08/18/2016) [-]
It is partly that, partly their lack of circulatory system similar to ours that would allow it to be transported around. Theres also the fact that animal cells become specialized during embryonic development, so they can only divide and form cells of a certain type. This means that when animal cells become cancerous they can invade surrounding tissue with the incorrect type of cell, which interferes with the function of organs. Plants in that sense don't really have "vital organs" like we do, they're not as affected. In plants their cells are usually totipotent meaning that they can still divide into cells of any type. Hence, they can still grow the correct multicellular structures necessary to live, just with a deformed shape.
#5660 to #5659 - shaunata
Reply +1
(08/19/2016) [-]
Very interesting! Thanks!
#5654 - chillybean ONLINE
Reply 0
(08/17/2016) [-]
Alright, don't know if this is the place to ask, but i'd like an answer and this is the only place i could find that might help (google was just not answering me)

if 733 = 70%, what is the total 100%?
#5657 to #5654 - platinumaltaria ONLINE
Reply +1
(08/18/2016) [-]
733/0.7=1047.14286
#5655 to #5654 - mublerking
Reply 0
(08/17/2016) [-]
if you want N percent of X you take X*(N/100) so we want 70%, so we have X*(70/100)
we know that 70% is 733 so:
733=0.7*X

thus X=733/0.7≈1047
#5656 to #5655 - chillybean ONLINE
Reply +2
(08/17/2016) [-]
Thanks, unfortunately i can't retain shit so I'll probably have to ask again if I ever need it again.

But thank you for the answer, much appreciated