All Questions
Tagged with temperature everyday-chemistry
11 questions
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Is there any chemical that can react with two different chemicals to generate heat or cold? [closed]
For example. There are three chemicals. Chemical A,B,C
Chemical B react with Chemical A = heat
Chemical B react with Chemical C = cold
Is there any chemical available like this? And is it safe to ...
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3
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0
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565
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Does the anti-rust properties of bluing carbon steel disappear at a certain temperature?
Yesterday I blued my new carbon steel wok over a very high (200K BTU) burner which is capable of getting the wok to 1000+ degrees with ease.
I understand that bluing adds a rust-resistant layer which ...
- 131
8
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3
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Does motor oil get more viscous when heated & what is the meaning of the SAE motor oil code?
The motor oil in my 2004 Pontiac Vibe is 5W-30.
My (incorrect) understanding of this SAE nomenclature is that 5W means "Viscosity index of 5 in the winter" (or when really cold - like $\pu{-30 ^\...
- 188
4
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2
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644
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Does hydrogen peroxide - urea become more active when illuminated?
Dentists' tooth whitening systems and consumer kits use gels containing carbamide peroxide, also known as hydrogen peroxide - urea.
Dentists use a light activator: (image from Wikipedia).
Consumer ...
- 519
37
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5
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54k
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A glass of water with ice-cubes in it. Where's the water the coldest; at the top or bottom?
Suppose that I fill a glass with ice water. As the ice melts, it cools the water around it. Given that cold water is denser than hot water, I would presume that the cold water would sink to the ...
- 497
5
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2
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8k
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Safe endothermic reaction that gets below freezing?
I have a project/idea I am working on but I am only 14 years old and I need some help.
I'm looking for an endothermic reaction that gets below freezing, but the chemicals before the reaction and ...
- 59
3
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2
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1k
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Why does superglue lose strength at high temperatures?
I'm not a chemist. When I superglue my fingers together, by accident, I put them under warm water to peel off the superglue. Why does superglue become less "sticky" at higher temperatures? Is it the ...
- 131
1
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0
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Does freezing tights make them more durable?
Various blog posts and articles suggest that freezing a pair of tights will make them last longer.
From a blog named Eclipsed Moon:
Put your tights in the freezer.
I thought that this was ...
- 189
14
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2
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417
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Why no thermal expansion for camping tents?
I know that solid materials expand when heated, which is called thermal expansion.
But what is happening to tent square or tent canvas of (plastic?) camping tents? I have noticed, that during the day,...
- 364
5
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2
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4k
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8
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1
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Why is bread warm at room temperature?
If I buy a loaf of freshly-made bread and leave it out at room temperature for a day or two, when I reach into the bag the air inside is much warmer than the rest of the room. Why?
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