Problem Statement of Series 3, Year 38
About the Competition Rules How to Write Solutions Results1... lazy river
3 points
Jarda is lying on his pool float in a water park and he is being carried away
by an artificial river current, when he notices his friend swimming toward him,
intending to capsize Jarda. His friend is swimming at speed
2... Mišo doesn't want to die
3 points
Mišo found an old radioactive source that contains
3... non-coloumbic
6 points
Fykosaurus discovered a previously unknown type of interaction while being in
a lab. He found a small spherical object in a dusted cabinet. When he placed
a point mass with a mass
Hint: Try to find an analogy to a force you know.
4... forever Young
7 points
Marek has a double slit with negligible slit width, immense slit height and
a distance between the slits equal to
5... a toast down under
10 points
P... bread
9 points
We can squeeze bread quite well, as there are a lot of cavities filled with gas. Determine the inner surface of all such cavities in a sourdough loaf.
E... salted
12 points
Determine the specific heat capacity of kitchen salt.
Instructions for Experimental TasksS... electrochemistry 3 – kinetics and efficiency
10 points
- In previous parts, we used a model where Gibbs free energy increases linearly
and then decreases depending on the reaction coordinate to calculate the change
in activation barriers for both the forward and the reverse reaction. Consider
the slopes of these straight lines in figure 4 of this part of the series to
be
for the forward reaction and for the reverse reaction. Find the relationship between and and . – 3 points - It is possible to use an electrochemical cell to compress gases instead of mechanical
pistons. Consider a simplified model of such a cell for hydrogen compression. Assume
we have two standard hydrogen electrodes in beakers, filled with a solution
of concentration
. One electrode is connected to a reservoir (i.e., an infinite volume) of gaseous hydrogen with a pressure of , and the other is also connected to hydrogen of the same pressure, but only a volume of . We apply a voltage of to the cell, causing gaseous hydrogen to start forming at the second electrode. We reached a pressure of in the bottle at time . How long did it take for the pressure to increase to of its maximum value? Assume the beakers with are large enough that their concentrations remain constant during the process, and everything occurs at a temperature of . – 5 points - Consider a Carnot heat engine with the corresponding efficiency, where the cooler temperature
is
. What is the temperature from which would this heat source achieve higher efficiency than the electrochemical reaction of hydrogen forming water, which also occurs at temperature ? For water vapor, use and , both valid at a temperature of . – 2 points