'Black' bees and 'yellow' bees

[For want of a better word]

Thanks folks,,,,,,

Nice to see loads of BALLS on the forum !!!
​

moth or otherwise !

 

[Davelin]

And - I seem to remember from O level chemistry - a great example of super-cooling a liquid to a meta-stable state, from which it can then be made to re-crystallise very quickly by throwing in a small solid crystal of Naphthalene

Presumably this is just the same as honey, only faster?

As someone who used to teach Science when it was proper Science I protest.

This is a physical change, not a chemical one and thus should have been in your 'O' level Physics syllabus

 

[Firefly]

As someone who used to teach Science when it was proper Science I protest.

This is a physical change, not a chemical one and thus should have been in your 'O' level Physics syllabus

D'you know, it's a long time ago (40 years!!), but I think we did it in both!!

 

[drstitson]

why do you think they introduced "combined science". saves the arguments!

 

[Davelin]

why do you think they introduced "combined science". saves the arguments!

They introduced combined science because there were no Physics or Chemistry teachers, only Biology, but that's another story.

The fascinating thing about naphthalene was that once you had supercooled it and then seeded it so it crystallized, the temperature went up without any tangible form of heating. Ask anyone under 35 about latent heat!!

 

[RoofTops]

Hmmm...there is naptha and naphthalene. Note the extra "h" in the second. They are not the same thing. The latter is used in moth balls but the former is a generic term for a mixture of flammable hydrocarbons.

 

[oliver90owner]

D'you know, it's a long time ago (40 years!!), but I think we did it in both!!

Probably. Things like freezing beakers to wet benches by blowing bubbles through ether (yes, we did that) and making crystals of copper sulphate, and other salts. That was by growing a (large) crystal slowly, over several weeks, so the opposite (small crystals from a super-cooled liquid) was likely a good comparison even if a little 'cheating' by the teacher! We made small crystals by dropping HCL into a saturated common sdalt solution.

RAB

 

[For want of a better word]

I had to suffer Physical Chemistry... or was it Chemisty physics... Van der Vall's equations and stuff, covalent bonds, Bohrs radius etc etc... best anaesthetic ever !

Like beekeeping and carpentry the crafts merge......................

Wassail !