Skip to main content

All Questions

-3 votes
1 answer
327 views

Vinegar reaction [closed]

please could someone help me. I poured white vinegar over a small hole where ants where coming out in my patio steps. There was some sand on the step and it started to bubble and fizz. We have been ...
Tina's user avatar
  • 17
3 votes
1 answer
181 views

Why does the rusting process start from the bent/squeezed portion of iron?

I have noticed that the rusting of iron starts from the squeezed or bent parts of iron piece. I want to know what is the peculiar reason for the observation that rusting starts from bent or irregular ...
user616424's user avatar
3 votes
2 answers
9k views

How to dissolve calcium sulfate fast?

I would like to dissolve $\ce{CaSO4}$ in a hardened condition (e.g. gypsum board) as fast as possible. I have seen in posts about $\ce{CaSO3}$ that vinegar and sulfamic acid are able to dissolve it. ...
Joe's user avatar
  • 33
21 votes
1 answer
2k views

If aliens lived in a hydrogen (or any flammable gas) based atmosphere, would they perceive oxygen to be flammable?

Energy, fuel, and oxygen are needed for a fire to burn. In a hydrogen chamber, if there was a pipe spewing small amounts of oxygen, could you light the oxygen on fire as it began to mix with the ...
Howzieky's user avatar
  • 321
2 votes
1 answer
58 views

silicon nitride and sCO2

I want to use silicon nitride ball bearings with a reciprocating piston that will be powered by $\ce{CO2}$ liquid heated to $\mathrm{288^oC}$ becoming super critical. That temperature is the maximum ...
cerial's user avatar
  • 23
7 votes
1 answer
2k views

What typically happens to H2 molecules released into atmosphere (with no spark source)?

I'm wondering what happens when $\ce{H2}$ leaks from say a transmission pipe in an unenclosed area. No immediate source of ignition, I know it rises more quickly than helium (x2 I believe) and ...
wide_eyed_pupil's user avatar
20 votes
2 answers
45k views

Why does superglue ignite cotton?

Cotton is mostly cellulose, a plant saccharide. Superglue refers to a class of cyanoacrylates. What is it about the two that causes ignition? I'd imagine that the cellulose in cotton is in its ...
Dissenter's user avatar
  • 19k