Wikipedia:Reference desk/Archives/Science/2019 July 13

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July 13[edit]

planet with size Mars can not impact with earth[edit]

It said that any mars sized planet impacted earth to form moon. my calculations show it is impossible .--Akbarmohammadzade (talk) 04:01, 13 July 2019 (UTC)[reply]

Giant Impact Hypothesis- the planet Theia — Preceding unsigned comment added by Akbarmohammadzade (talkcontribs) 04:03, 13 July 2019 (UTC)[reply]
(here to learn, not answer questions) Did you take into account the fact that the solar system wasn't settled yet, then? Usedtobecool ✉️  06:35, 13 July 2019 (UTC)[reply]
Have you read Giant-impact hypothesis? What do you think is impossible - that such an impact could have occurred, or that Earth would have survived the impact, or that the moon could have resulted from the impact and found a stable orbit?-gadfium 06:50, 13 July 2019 (UTC)[reply]
How about you show us your calculations. ←Baseball Bugs What's up, Doc? carrots→ 07:10, 13 July 2019 (UTC)[reply]
NO! I mean, if the calculations were validated and published in some (real) physical review, at some point it will show in wikipedia. But Ref Desk is not place to discuss such hard science Gem fr (talk) 08:16, 13 July 2019 (UTC)[reply]
The OP has stated a premise. It is totally reasonable to ask what the basis of that premise is. ←Baseball Bugs What's up, Doc? carrots→ 12:22, 13 July 2019 (UTC)[reply]

why we suppose that it impacted when in such case two planets only start to form couple planet system? in fact when it was nearing the earth , new planet get the earth out of its orbital , and for the reason of gravity field effect , two planets only were been rotating each other.--Akbarmohammadzade (talk) 10:06, 13 July 2019 (UTC) we see Pluto and Charon do so--Akbarmohammadzade (talk) 10:07, 13 July 2019 (UTC)[reply]

WP:NOR Gem fr (talk) 10:37, 13 July 2019 (UTC)[reply]
The two would need to be headed on a collision course, not a near miss. This seems extremely unlikely today, but there were a lot more such objects flying around the solar system in the early days (all the craters on the Moon, where they are preserved, are a fair indication of that), and over billions of years most of them either hit the Sun or planets, were ejected from the solar system, or found a stable orbit. SinisterLefty (talk) 13:25, 13 July 2019 (UTC)[reply]


It's a little late to submit papers, but the Ames lunar summer science summit is in a few days (registration open through July 18!) and this year is sure to be a big one - commemorating fifty orbits since the return of Apollo 11! :Anyway, without being a little too blunt, I'm inclined to quote my own words from a couple of months ago responding to amateur research here on Wikipedia's science reference desk. "Until you have established credibility in these fields by following well-established career-trajectories working toward the professional level, the experts don't really care what opinions you have about their work. You are free to critique advanced physics - or to complain that you don't understand it - but it will be about as productive as if you complain about the coaching strategy for a professional sports team. Your opinion carries no weight, and your critiques don't merit attention, because you aren't playing in the same league."
So for example, when Apollo 17 astronaut-scientist publishes an outside-the-mainstream opinion on planetary impact, like the famous Moon’s Origin And Evolution: Alternatives and Implications,... we take note of his idea, even if we don't accept every single detail; but we look at it because he's worth listening to and has previously established his credentials; but when random Wikipedia contributors do the same, we sort of hold them to a different bar. It's not necessarily the case that scientists disagree with your independent research: it's more the case that scientists don't care enough about your work to actually bother looking at your calculations. It is a harsh and competitive world, and if you haven't proven your mettle by conducting well-respected peer-reviewed research before the time you finish formal university years, well... then, the scientific-community-at-large is too busy studying the work that other bright people have done on these interesting topics.
Nimur (talk) 18:11, 13 July 2019 (UTC)[reply]

There are examples of amateurs making respected contributions to science. Astronomy, Chemistry, and Archaeology are fields that come to mind. See, for example, “Amateurs and professionals in chemistry: The case of the periodic system” You need to do your research, and if you ask politely and present your work concisely, some experts will look at your work. After that the road to wider recognition is to get published in a peer-reviewed journal. You do not necessarily need to be an expert in the field to achieve this. The good thing about being an amateur is that amateurs will sometimes bring a different perspective to matters. The not so good thing is that you need to do a lot more homework to be able to speak the language of whatever the applicable field is. Sandbh (talk) 00:03, 14 July 2019 (UTC)[reply]

Producing CO2 from vinegar and baking soda[edit]

At a science fair I saw a"baking soda and (colored) vinegar volcano". Was nice.

There was an argument how much CO2 is emitted (starting with a 9 years old that was worried it will contribute to global warming :) )

So my question is as follow: How much (in grams) baking soda and how much (in liters) 5% vinegar produce 1 cubic meter of CO2 under 1 atmosphere pressure? אילן שמעוני (talk) 18:00, 13 July 2019 (UTC)[reply]

From these, one mole of CO2 will occupy 24.5 litres at room temperature the (molar volume – it's the same for any gas that one mole of it, a very large but standard number of molecules, will occupy the same volume). i.e. Your "one cubic metre" will need of CO2 (that's about 40 moles of it, which gives many experienced chemists a quick idea of if they're talking about beakers or tank trucks of it)
The next bit is chemistry.
To make a mole of CO2 you need at least enough of each ingredient. You could use a stoichiometric mixture, but usually one is in excess (and doesn't react, because it's run out of the other reactant).
Baking soda is sodium bicarbonate, NaHCO3
Vinegar is acetic acid, CH3COOH (5% by volume, here)
Their reaction is NaHCO3 + CH3COOH → NaC2H3O2 + H2O + CO2
This isn't quite the full detail of the reaction,[1] but it's OK to show us the end result. What it means is that we need one molecule of baking soda to react with one molecule of vinegar, to give us one molecule of CO2. To make our cubic metre of gas, we need of each. As liquids and solids are more dense than gases, that's a lot less than a cubic metre of those! But how much?
A molecule of baking soda (NaHCO3) has a molar mass of 84.0066 g mol−1 (I cheated and looked that up from WP). I could work it out too, by adding up the individal atomic masses for each of the four elements in it (and counting three times for all those oxygens). That's (real chemists will object to my approximations here)
Acetic acid is 60.052 g·mol−1
So we'll need at least of baking soda. The vinegar will need 2.45 kg of acetic acid, or about 2.33 litres of it. But as this is 5% vinegar, that's 47 litres of vinegar.
So overall, to make a cubic metre of CO2 gas from one of these volcanoes, that's a couple of sugar bags of baking soda, mixed with a dustbin of vinegar. Quite a bit for a science fair project! But maybe, you could catch the gas bubbles produced and measure them?
Andy Dingley (talk) 18:31, 13 July 2019 (UTC)[reply]
Thank you! Not only an answer, but detailed walkthrough! אילן שמעוני (talk) 19:09, 13 July 2019 (UTC)[reply]
This is getting out of hand, so I am collapsing this. There are things below that are not debate about climate change, but there are few of them. As a rule of thumb, when an adequate answer has been provided that covers everything the question asked, one should refrain from adding stuff to answer questions that were not asked. TigraanClick here to contact me 08:06, 16 July 2019 (UTC)[reply]
While it certainly is such a trivial amount that it can be ignored, kids sometimes don't grasp relative scales. So, you might suggest they plant a tree to make up for it. Even a tiny tree ought to do it. SinisterLefty (talk) 20:00, 13 July 2019 (UTC)[reply]
"Wood is composed of up to 50 per cent carbon". [2] 1 m³ of CO2 weighs about 2 kg (depending on temperature), [3] so your tree would need to grow to 4 kg to offset. Alansplodge (talk) 21:58, 13 July 2019 (UTC)[reply]
It's also a fine opportunity to distinguish between capturing, and sequestering: if you plant a tree and it transforms carbon dioxide from the air back into a solid form of plant matter, by way of photosynthesis... well, what happens to those atoms of carbon after the tree dies, rots, and evolves into a new form? In the short term - perhaps just a few years - that organic matter will rot and oxidize the carbon, meaning that each atom of carbon will probably evolve back into carbon dioxide molecules, and be re-released into the atmosphere.
On the other hand, if we bury the dead tree, and provide specific conditions, ... it has the potential to evolve into coal, and (perhaps) later into e.g. natural gas and other fossil-carbon. This may take a very long time... but as long as it stays underground, those atoms of carbon are not floating through our atmosphere.
And then, if some future civilization digs that coal out of the ground and burns it to power a heat-engine for a new millenium, they may re-release those very same atoms back into the air...
What we really want is to take those atoms of carbon and put them inside some long-term biotic process that converts them into an almost-geological substance that won't be evolving back into atmospheric carbon dioxide...
Nimur (talk) 22:54, 13 July 2019 (UTC)[reply]
Even if 100% of the carbon goes back into the atmosphere in a few decades, that would help slow global climate change, allowing us time to come up with other solutions, or at least move our houses off the coasts. SinisterLefty (talk) 01:07, 14 July 2019 (UTC)[reply]
Do you have a house on the coast? My family do. And I wondered if I needed to care. Answer is no. f*ck the scaremongers. At worse, stilts would be needed, and that's it. Global climate will keep changing anyway, so the question is rather: should we fear that Antarctica turn back to a rain forest, or that the Earth turn into a snowball? Is it good, or bad, that we may help skip next glacial period? I (and you) will be dead by the time those question really matter, anyway, so my answer is: just solve current real issues. Gem fr (talk) 09:44, 14 July 2019 (UTC)[reply]
If global warming is inevitable, just relax and enjoy it. ←Baseball Bugs What's up, Doc? carrots→ 11:41, 14 July 2019 (UTC)[reply]
Yeah, Gem: it's nice that you live somewhere where you can easily put your house on stilts, or build a new one. Are you going to tell us how to do that with dozens of large cities worldwide like London, New York and Delhi. Apres moi, le deluge? {The poster formerly known as 87.81.230.195} 2.122.177.55 (talk) 20:17, 14 July 2019 (UTC) [reply]
Actually, I'll never need stilt: this is why I am so angry at those f*cking scaremongers. And you better check your data (and turn angry, too), if you still believe them. People who will need stilt are those who should already use them (in Polders for instance). Ever heard about Raising of Chicago? Scaremongers somehow always fail to mention that
1. movement of the land matters more than change of sea-level.
2. sea-level has been rising for millennia, and concerned places are already dealing with it. A change is barely visible.
3. nobody (almost) cares. If they care, they just need to build, right now, at a proper higher height. (well, actually, I know a few place where they care, because it has been happening for a long time -- climate change having nothing to do with it--). So that, by the time it becomes a problem --this needs decades--, if it even ever comes, it is already solved. but Nooooo... why use simple, cheap solutions, when you can owl The End Is Nigh, let's destroy the civilization, stop giving health care to elderly, etc, to save New York, eh? Gem fr (talk) 21:27, 14 July 2019 (UTC)[reply]
Delhi is more than 200 meters above sea level so that's a total brain fart.--TMCk (talk) 21:29, 14 July 2019 (UTC)[reply]
And kudos to reasonable Gem which whom I apparently just edit conflicted.--TMCk (talk) 21:34, 14 July 2019 (UTC)[reply]
I don't see putting everything on stilts as a cheap and easy solution. How do you do that with skyscrapers ? Best plan I could see is to abandon ground floor (or use it to store junk you don't much care about) and make 2nd floor into new ground floor. Then raise all the roads by one story, too. Still a massive project, but cheaper than rebuilding inland or at same site on stilts. SinisterLefty (talk) 03:16, 15 July 2019 (UTC)[reply]
It's GREAT to see my humble question spurring such a discussion, and I think I have two quite important remarks: A The natural process in forests is that carbon remains locked as long as the forest survive. Dead trees rot and serve as compost for new trees. So yes - planting a forest is a long term solution. B Gem fr view is totaly wrong, not because sea levels rising, but because rapid climate change. Already vast parts of Spain and the Sahal are turning to desert. Record-braking temperatures are nearly an annual event. Farming depend on weather. The obvious hunger that will follow will be the end for at least tens of millions, I think more like 2x10^9 . And yep, Gem fr, you will pay a heavy price too, Food prices will skyrocket. אילן שמעוני (talk) 11:59, 15 July 2019 (UTC)[reply]
This needs answer, but Ref desk is no forum so I put it small. Well, if global warming is your concern, be informed that A planting a forest increase it, in two ways: greatly decrease albedo, increase the level of humidity (water is a more potent GHG that CO2). funny, isn't it? And B: "rapid" in a geological sense is still invisible in a human life. And C your are telling crap about Sahel (notice the sharp drop in rainfall when global temperature were falling 50-70, and the recovery since temperature rise onset in the 70s; so much so that it had been hypothesized that the whole Sahara is a product of a global cooling event; it probably need 4-6 °C more to return to forest state). And D don't imagine the climate will stop changing because of any CO2 experiment;All these effort to get a cooler climate could very well succeed in bringing us another disaster; do you want to take that chance, or do you have rather "risk" London enjoy the climate of Barcelona (not gonna happen, alas)? And E You are parroting Erhlich's crap about global hunger, and you are wrong just like he was, for a simple reason: farming depends on farmers much more than on weather, adapting to the weather being an important part of their job. Now, if you think food will be scarce and expensive, put your money where your mouth is: start a basic food producing business, so you will both get rich and help all humanity; if you are right, I will be glad to buy you basic rice for its weight of gold (no gonna happen, of course). Bottom line: climate will be changing whether you like it or not, so enjoy and adapt as need be (not forgetting that, for adaptation, the more energy you can muster, the better); and, until then, just cope with really happening problems of now, that should have priority over possible problems of the future. Gem fr (talk) 14:45, 15 July 2019 (UTC)[reply]
I don't know about "forum yes/no". In Hebrew Wikipedia discussions such as this are accepted, even welcomed. but maybe here the rules are different.
You seem to be overzealous about the subject, and you defy the overwhelming consensus among climate researchers. Best of luck with that.
I've been a farmer for nearly a decade. Your claim about "depends on the farmer more then the weather" is outright wrong, and that is from experience. One Heat wave on the season that formerly did not have heat waves at all and your crop is 20% than what it should be, and the quality is poor. However, farming is a very boring work, so I do not do that anymore. But I DO put my money where my mouth is: the investment fund I chose is farming-companies oriented, especially adopting genetically modified variants of wheat, barley and some legumes.
אילן שמעוני (talk) 16:48, 15 July 2019 (UTC)[reply]
While I believe that human-caused global climate change will cause increased sea levels, I don't believe it will cause lack of food. Generally, hotter temps means more evaporation from oceans, and this leads to more rainfall on land. So, with notable exceptions, the land will be warmer and moister, which is an ideal climate for growing many types of crops. Eventually, vast areas such as Siberia should open up to farming, too. So, more farmable land plus warmer and moister equals higher outputs. Of course, major adjustments will need to be made, such as putting in the infrastructure to farm these new areas, and switching to crops that survive warmer, moister environments. Those farmers in what will become a desert will need to move elsewhere. SinisterLefty (talk) 20:08, 15 July 2019 (UTC)[reply]
See the intro of ref desk: We don't answer requests for opinions, predictions or debate.; actually, we do, as long as the debate is reasonable and kept under control and nobody complains.
If you refer to this famous crappy 97% agreement, well, I perfectly fit in. I am quite confident that science will ultimately bulldoze the massive amount of scaremongering donkey manure produced by donkeys calling themselves scientists, like this one. And that, this day, you will tell yourself "gee, this guy of wikipedia I don't remember, was actually right".
Your investment seems reasonable to me, because it actually has just nothing to do with climate change, and aims at solving actual real issues. Gem fr (talk) 22:28, 15 July 2019 (UTC) [reply]