#chemistrychallenge 3

in #steemstem7 years ago (edited)


Once more I ( @jaki01 ) let my #chemistrychallenge run under the SteemSTEM flag to support this still growing science community which in my eyes adds a lot of value to our Steemit community!

What could be more fun than activating your brain and at the same time having the opportunity to win up to 15 STEEM. :-)

Rules - what are the requirements to win the prize?

The winner is the first person to post the correct solution (correct number and correct unit; solution process required). The prize for the correct answer is 15 STEEM. We will send it to the winner immediately after the article is paid out (7 days after posting).

If nobody is able to determine the solution before Sunday, May 14th, 2017 at 10 pm (German time!) the prize (15 STEEM) will be added to the next competition (bringing that one up to 30 STEEM!).

Liquid fluorine:

                                                              Source: Par Fulvio314


Your Chemistry Challenge to Solve:


Fluorine can segregate into atoms according to the equation

F2      ------->      2 F        ∆H = + 158 kJ

That means the energy one needs to split 1 mole F2 amounts to 158 kJ (kilojoule).

Question:

What color would have a photon, which had exactly the energy necessary to segregate one single F2 molecule into two F atoms?

Some (possibly, some may be to trick you) Useful Constants:


  • Speed of light: c = 3.0 x 108 m/s (meters / second)
  • Planck constant: h = 4.136 x 10-15 eV∙s (electron volt ∙ second)
  • Faraday constant: F = 9.65 x 104 C/mol (coulomb / mol)
  • Avogadro constant: NA = 6.022 x 1023 mol-1 (atoms / mol)
  • jaki01's constant: j = 6.488 x 1016 awesomes / science
Sort:  

Nice challenge! Can not wait to see more :) and congratz to @room101

Ok, here goes:
If it takes 1 mole of F2 158kJ to break up, then one molecule of F2 would require a photon with this much energy:
(158x10^3 J)/6.022 x10^23 mol^-1 = 2.62 x 10^-19 J
We calculate the frequency of the photon like this:
E = hv
so
2.62 x 10^-19 J = 6.626x10^-34 Js x v
v = 2.62 x 10^-19 J / 6.626x10^-34 Js = 3.960 x 10^14 s^-1
Now we convert this to a wavelength for that photon:
c = lv (sorry: l = lambda)
l = c/v = 3x10^8 ms^-1 / 3.960 x 10^14 s^-1 = 7.575x10^-7 m = 757.5 nm

... which is the wavelength of a photon of red light.

Very well (and fast) done! You are the winner of this round: congratulations! :-)

Great! Thanks a lot for the opportunity. Great idea, to do this on Steem, btw. Very fun, too.

Cool idea for a contest. Next time I'll try to solve it for fun before I read the answer.

It's all @jaki01's creativity. He writes the the great questions and we are pretty lucky that he publishes his STEM quizes under the steemSTEM banner from time to time! Lets us dole out more rewards :D

Once again I'm too late to the party... Still: Awesome contest, create creativity and interesting approach. Go SteemSTEM, go!

Friggin' inorganic chemistry probably the one college class that kicked my ass the most--but I did well enough I guess--but I'm not touching this.

Upvoting because I think this type of educational challenge is a great use of Steemit. Who knows how far stuff like this can go?

Thanks so much for your support! I hope that in future the SteemSTEM community will grow, so that more and more interesting science articles may appear on our Steemit platform.
Btw.: why don't you try to "touch this"? :)

Quickly found the winner)))
Interesting contest, i follow!
Good luck @steemstem!

Colour White!

Maybe, maybe not ... I will tell you, if you are right, after I saw your calculations. :)
(Check under "Rules": "solution process required".)

okay,im waiting.....

Oh, just check out the solution of @room101 . He has already solved the question.