Self If all ocean water evaporated, it would leave behind about 4.8 × 10^16 tonnes of salt (forty-eight quadrillion tonnes), enough for an average salt layer about 62 meters thick across the seafloor.

Assuming:

average seawater salinity of 35 g/kg

total ocean volume of 1.335 billion km\^3

seawater density of 1,027 kg/m\^3

ocean area of about 360 million km\^2

and a solid halite density of about 2,160 kg/m\^3

First, total ocean water mass:

1.335e9 km\^3 x 1e9 m\^3/km\^3 x 1,027 kg/m\^3
= 1.371e21 kg of seawater

Then total dissolved salts:

1.371e21 x 0.035
= 4.80e19 kg of dissolved salts

That's about 4.80e16 tonnes of salt.

Turn that into solid salt volume:

4.80e19 kg / 2,160 kg/m\^3
= 2.22e16 m\^3

Now spread that across today's seafloor:

2.22e16 m\^3 / 3.60e14 m\^2
= 61.7 m

So if all ocean water just disappeared and all the dissolved salts were left behind, the seafloor would be covered by an average salt layer of about 62 meters.

Obviously real life would be messier than that, since different salts precipitate at different stages and it would not settle into one perfectly flat, uniform layer, but as a back of the envelope estimate, about 60 meters is the ballpark.

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[Request] How much did this Wrigley Field Cup Snake cost to drink?
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[Request] Secondary question to this- how far backward would the ship be pushed assuming no wind or waves in Salt water?
https://upload.wikimedia.org/wikipedia/commons/e/ea/BB61_USS_Iowa_BB61_broadside_USN.jpg

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[Other] Question about the viability of rocket sled launch
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[Request] Is this possible to trigger airbag just by kicking the sensor ?
https://www.youtube.com/shorts/JoVEHeabrHg

https://redd.it/1sp5t32
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[Request] What would happen to the Lunar Orbit if the moon magically gained 25% mass (size optional, unless it could be a big factor)
https://redd.it/1spirkt
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[Request] if a person was attending a live concert while simultaneously listening to a live radio broadcast of it, how far away would they need to be to hear the radio noticeably sooner than the “live” sound?
https://redd.it/1spiy5e
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[Request] How strong does bryce James need to be at least in this photo?
https://redd.it/1splqf3
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[request] Is it true That a single cow can feed a family for a whole year ?
https://redd.it/1sppkfo
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[Request] Could the drink be cooled that fast?

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[Request] Could a human smoke 500 cigarettes and survive?
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[Request] Is it possible for one second to pass on Earth with absolutely zero rainfall on our planet? What will be the chance of that?
https://redd.it/1sprsgl
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[Self] I did this doodle of an equation which is actually equal to 01
https://redd.it/1spv9lu
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[Request] Is this accurate? Or just an exaggeration?
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[Request] how tall was the shockwave seen at ~2 seconds into the video?
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[request] How many Newtons of force was required for this throw and (bonus) what % of humans could realistically complete it successfully?

https://redd.it/1sq2c3r
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[Self] I calculated the rough size of the crowd at Trumps b-day parade.

https://redd.it/1sq43js
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