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Topic: Chemistry Scavenger Hunt  (Read 19615 times)

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Offline Alpha-Omega

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Re: Chemistry Scavenger Hunt
« Reply #15 on: January 02, 2008, 11:30:42 PM »
Hey Typo in that oil and water answer  the oil is NON POLAR...water layer is POLAR....


Offline Alpha-Omega

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Re: Chemistry Scavenger Hunt -Your Last Problem
« Reply #16 on: January 02, 2008, 11:35:49 PM »
If you dissolve ammonium nitrate in water then the temperature of the reaction mixture falls.

The temperature falls because heat energy is taken in by the reaction mixture. The heat energy is taken from the surroundings.

Dissolving ammonium nitrate in water is an example of an endothermic reaction

Offline ARGOS++

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Re: Chemistry Scavenger Hunt
« Reply #17 on: January 04, 2008, 11:14:36 AM »
Dear 1337Monk;

Only a few notes to your Questen 3:

Dear Yosh you are absolutely right!,  Absolut nobody can guarantee for the 5Tb. Hershey’s Sirup;  ─   FDA at last!    (Thank you for your mail.)
Food Calories of Hershey’s Sirup or similar may be good for “weight watchers” or skinny girls, but not for science;    ─   A “food calorie” is only one of several definitions of calories!

But there is a lot wrong with this Question if it is still “congruent” reproduced with its original version!
  • A.)   The term Calories (with capital “C”) for 1’000 calories should not anymore be used since several decades, because its possibility for misinterpretation. The term kCalories is strongly recommended instead!
  • B.)   Using the term kCalories instead manifests/confesses that the whole Question must be formulated very thoughtless, because to “apply” 250 kCalories  to only 0.050 kg of water with its heat capacity of 1.0 kCalorie °K-1 kg-1  can not be thought in any other way!
    (The division is left to everybody.)
  • C.)   Only if we use “smale” calories ( = 0.001 kCalories = 1.0 gram Calorie) sense can be given to the Question, because  in this case ΔT = 250 calories / 50g / 1.0 calorie °K-1 g-1 = 5 °Kelvin.
    This is now possible, because the heat capacity of water is nearly constant over the liquid temperature range.

To make always “a Picture” is still the most impotant to do.

Good Luck!
                    ARGOS++

P.S.: I still believe that we should ban discussions “with”/about FDA into a quite different “Sub-Forum”, because FDA is much more a Business-Protection-?Regulatory?, than any kind of science.  Sorry!, But that’s not only my point of view.
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