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Author Topic: Is there a material that changes colour due to temperature and humidity?  (Read 2220 times)

Offline thedoc

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afsane asked the Naked Scientists:
   Dear Mr or Mrs
salutation
is it possible to guide me?
I need a series of material that change their color by change of temperature and humidity(I mean respond to specific conditions of time , temperature,humidity,pressure and the presence or absence of certain chemicals by changing color)
now can you help me to find of list of these material?(paper or reference for find)
thank you for attention
What do you think?
« Last Edit: 15/10/2015 11:50:03 by _system »


 

Offline Bored chemist

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The best known substance that changes colour with humidity is almost certainly this
https://en.wikipedia.org/wiki/Cobalt(II)_chloride
 

Offline Lor

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I read about colbalt chloride after clicking the link in your answer. It stated it is a substance of very high concern-svhc-by the EU. There are coffee mugs you can purchase which change color and/or images when filled with a hot liquid. Is this what is likely added to the ink or paint and if so , how safe is that considering it being washed in a dishwasher ? Is it something dangerous to be used around food/liquid you drink or eat ?
« Last Edit: 22/10/2015 11:51:56 by jazzderry »
 

Offline Bored chemist

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The coffee mugs etc probably use something like this
https://en.wikipedia.org/wiki/Liquid_crystal_thermometer

But the OP asked about humidity as well as temperature.

Incidentally why is it that so many people think "cobalt" has two Ls in it?
 

Offline Lor

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for the same reason people fail to use apostrophe marks correctly. I can be snarky too. ;D
 


Offline Lor

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I was only poking you back, wasn't trying to be an asshat, sorry. but here it is-

             the punctuation mark ʼ used to show the plural forms of letters or numbers (as in dot your i's and cross your t's or in the 1960's)

from Merriam Webster
 

Offline Bored chemist

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Oh, I see you mean the optional one you can use if it is needed for clarity.
Well, since you knew what I meant, it wasn't needed.
OK, perhaps it's a "wrong side of the pond" thing since you are citing an  English dictionary that isn't actually English.
Here's the authentic version.
http://www.oxforddictionaries.com/words/apostrophe

 

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