Answer 1:
This was a very interesting video, but
unfortunately I cannot think of how this happens.
I have also tried to repeat their experiment but
was unsuccessful. Here is my analysis of what
was shown in the video. Step 1) Baking soda
+ vinegar --> Sodium acetate + water + carbon
dioxide NaHCO3 +
CH3COOH --> CH3COONa +
H2O + CO2 (This is the
classic volcano demonstration) Step 2) Cool
the solution in the freezer The first reaction
is exothermic (releasing heat) so the solution is
cooled back to room temp. Step 3) Add
calcium acetate to calcium bicarbonate I
thought this was a mistake as the first solution
made was sodium acetate. They also showed the
solution being added to a solid they call calcium
bicarbonate. Calcium bicarbonate is always in an
aqueous solution so they likely meant calcium
carbonate.Either way there is not much of a
chemical reaction that would occur
here. Step 4) Add ionized salt I believe
they meant Iodized salt. This salt is sea salt
which has NaCl (your common table salt) as well
as some potassium iodide (KI).Still - not so much
of a chemical reaction - just some equilibrium
occurrences with a mixture of salts Step 5)
They boil it up, mixing constantly I think due
to such a large amount of salt, they heated the
solution with mixing for everything to
dissolve Step 6) Let it cool you may have
observed that when the solution was poured out it
was white and cloudy but in the last frames it
was clear. They use the argument that
contact with the air makes substance lose its
"polar ability" - I'm lost here, this just doesn't
make sense to me. They have added many polar
molecules to a solution - there isn't anything in
the air that will take that away. Thinking
back to step 3 - the "typo" of using calcium
acetate -- mixing calcium acetate with alcohols
can result in a moldable "jelly"perhaps they did
more than what they showed. If you're
looking for something else interesting involving
water I suggest checking out its effects of
surface tension and hydrogen bonding. The water
molecule H2O forms a network around
other water molecules. This is due to the strong
hydrogen bonding between the lone pair elections
on the oxygen with hydrogen atoms of other water
molecules. One way to demonstrate this is filling
a glass with water and then drop by drop adding
more water - you will find that it will fill over
the edge of the glass (like a muffin top) before
eventually spilling over. Another interesting
demonstration is to fill an ice tray with
distilled water or de-ionized water (the
diminished salt concentrations) allows for more
hydrogen bonding and when it becomes frozen you
will see a small spike of ice that grows out from
the center. |