Does sidewalk chalk ever disintegrate?
962206
Chalk is a calcium salt, and as such will probably dissolve in an acidic environment. Try  some common acidic liquids like seltzer (a weak acid) , vinegar or lemon juice.
842652
Based on this information, no, a diamond will not spontaneously decompose into graphite. It also does not imply that diamonds will last forever. It only states that diamonds are a better carbon based energy source than graphite.
173849
Not necessarily. Because the collision is elastic, the net kinetic energy of the rubber ball and the sidewalk is conserved. But that doesn't mean that each object on its own has the same initial and final kinetic energy.
872193
the surface that is writable to is meltable.\nwhen you erase it - it is melted and resmoothed.\nyou can then rewrite to it\nyou can do this quite a few times before it breaks down and becomes unusable
237074
Yes, but you notice the rubber ball is going slower now. Its because part of the momentum has been transfered from the ball to the sidewalk (eventually tranfered to the Earth itself).  This is called transfer of momentum.
570622
baby powder or weight-lifter's/rock climber's chalk should work just fine - my feet get clammy and slip, too . . .
584982
Yes Us paper currency will disintegrate. If you keep it in a damp environment long enough then it will start to mold and wear away. If you have US currency that has been damaged that go to the federal reserve web site and e-mail them. They will tell you how to package it and where to mail it to and they will replace it for you. As for coins I am not sure if they can rust but if they get dirty soak them in coca cola and they will be like brand new.
390529
If the unmovable object is not unbreakable, it WILL be broken. \nI believe this is an unanswerable question.
258149
Sell them to a company that shreds them and mixes them with concrete to make highways.  It's good for the environment.
643157
don't just throw it away. There are toxic gases in it.
1134410
The protective nature doesn't suddently stop.  It will likely erode with time.  They are just made out of layers of polymer (I think polyamide or maybe some polyester too).  Those polymers are subject to slow decomposition which is accelerated by acid.  Although the decomp is a very slow process.  So, would a 20 yr old vest still protect?  Probably.  But to the extent of a new one?  Probably not.
937059
depends on the fragile item.  Foam 'peanuts' work great for almost anything.  Newspaper, balled-up newspaper for heavier items, bubble-wrap, sponge
746653
I'm not entirely sure that that would actually explode.\n\nYou mixed salt water, salt substitute-water, alcohol, carbon and then the potassium p and ammon chlor.\n\nThe chloride and potassium may undergo a replacement reaction, but I doubt it would explode unless you actually lit it with a flame. You made great sidewalk salt though, go melt some ice :)
1053117
It is BUSTED, shattered, swept up and thrown away.\nIt happens, and you know what? That is just fine. Sometimes you have to put yourself first and forget about everything else!\nThat is what I am beginning to see, it only took some 30 years for it to sink in.
788031
take it to your local hazardis waste material center, they should know what to do with it:)
1087148
When in doubt throw it out.
821765
Plastic, in general, would not disintegrate. Some plastics are made to break up. It would depend on what it was made from. If it was organic it would evetually. If it was a petroleum product, it would not.\nCorrugated cardboard boxes are made from paper (wood fibers),  so they would disintegrate. The speed would depend on factors such as amount of water in the soil and insects.