Lets say by bad luck that a planet had only these 25 elements and none of the others were present at all anywhere in the planets crust / surface. Intelligent life evolves, what level of technology can they get to? Steam age seems like its no problem, nuclear fission is out but maybe they can eventually develop fusion?
Can they develop computers? modern medicine? launch rockets into orbit? can they eventually develop any kind of nuclear tech to create the “missing elements” they don’t have?
It might be useful to compare a “most used” list and a “total value used” list to this one.
Maybe we should just work our way through the table. No helium makes cooling superconducting magnets tricky, but I imagine they often have elements not on the list.
I think steam engines, electric motors and light bulbs are all possible only using those 25 elements but am I missing something? Theres no tungsten but they can have carbon filaments.
You can have aviation without aluminum. You can have electricity, though magnets for AC generators might have to be re-invented. You can even have electronics and computers. But high-performance components made from precious and rare earth metals will take 21st century technology to find substitutes.
The semiconductors used in modern computers are mostly silicon which is on the list, but require doping with small quantities of n-type and p-type dopants. Gallium (p-type) and arsenic (n-type) are among the most commonly used dopants and there are many others not among the 25 that are used for their useful properties. There are elements among the 25 that might substitute (boron and phosphorus, for example), but I’m not sure how well they would work in various applications.
Seems plausible. I don’t see anything mission-critical missing there, except, as you point out, for the radioactives. The noble gases are entirely lacking, of course, but they aren’t used for a lot.
Your question has an interesting application: with a handful of exceptions, you’re describing the elements available on a planet around a very early (in the lifetime of the universe) star, one that did not condense from a nebula enriched by the heavier elements synthesized in novae and supernovae. So your question could actually be rephrased as: is it even theoretically possible for a life to evolve and technology to arise in a first-generation star? Or does the universe have to wait for enough supernovae to “fertilize” it, before life can get going?
There’s also tin, which you need to go with the copper to make bronze. Pure copper does not make a good weapon.
I only see nickel and titanium (in the maybe list) that are not in the mammal list.
I’m somewhat surprised selenium isn’t in the plant list. I know some plants will take it up if it’s in the soil (garlic is one of them) and I assumed at least some was necessary for those plants. Could be wrong on that though. The wikipage on selenium agrees that some plants need it.
As far as photosynthesis, do you actually need any besides the usual CHONPS[sup]1[/sup] plus magnesium and potassium? Plants may use other elements but I don’t think they need any for just the photosynthesis.
[sup]1[/sup] CHONPS = carbon, hydrogen, oxygen, nitrogen, phosphorus, and sulfur. The big six for biology.
Out of the first three rows of the periodic table we’d be missing Beryllium, Lithium and Aluminium as well as the noble gases, I imagine that would make some technologies impossible. Battery technology would have to have gone in a different direction for one.
Note that, while those 25 elements form the immense majority of a human body by mass (what the article actually talks about), they’re not the only components. Lithium for example is not in the list, but we do know it’s an antidepressant: only because we don’t know how we need it, doesn’t mean we don’t need it.
You can make a very large fraction of a modern airplane with only three elements - carbon, oxygen and hydrogen. This gets you carbon fibre and epoxy resins. If we allow nitrogen into the mix the resins are a bit easier, but it isn’t mandatory. Add silicon the mix and we can make things out of silicon carbide - which gets you some useful high strength high temperature capabilities. (Aircraft brakes for instance.)
There is some level of hammer/nail in arguments about the necessity of an element. There is a good chance that evolution would simply work around the lack of many of the trace elements. There are in life as we know it because they were available for inclusion, and served a useful purpose. This doesn’t mean that the purpose can’t be worked around. At least up to some sort of limit.
It is amusing that the current poster boy for the next big thing in materials is carbon. Just carbon. It isn’t what you’ve got, it’s how you use it.
Silicon in trace amounts… where would glass come from?
What specifically would the world be made of? The ground, the dirt, the mountains? ITSM the world would be essentially a big water ball if only 4% of the world is Calcium and other hard minerals, unless the world is a big soot ball of carbon…
Hmm, am I right in thinking that you can make a particle accelerator pretty easily with our 25 allowed elements? In which case you can eventually (at enormous cost) create other elements that are not present on the planet?
Can a particle accelerator create heavier elements from lighter ones?
Edit: md2000 I never said that the elements were in the same proportion as in the human body, just that those 25 elements an no others were found on this hypothetical planet. There could still be huge amounts of iron and silicon lying around just like there is on our planet.
Another side of this coin would be to describe plausible physical/chemical properties of an element (or its compound) that would be useful, but such an element does not exist. Somehow, we keep working around the absence of this hypothetical element, undismayed, and technology marches on. So, we in fact are living on a planet in which even 92+ are not enough to meet all applications, real or imagined, but technology seems open-ended nevertheless.
The therapeutic use of Lithium does not imply that it has any role in normal metabolism. The mechanism of action is unknown, but it’s not taken to restore a deficiency.
The truth is we simply don’t know. All water contains minute trace amounts of Lithium, and I suspect a study has never been done trying to raise mammals solely with artificially purified water with zero lithium in it. Lithium may be essential for mammalian biology or it may not be, the same goes for a number of other elements but for the purposes of this question lets assume that its not essential.