1) Molecular motions can be described by random walks 2) The state that nature chooses is based on maximizing entropy (and so minimizing Gibbs free energy) 3) Evaporation-condensation is an example of an equilibrium that forms at a Gibbs minimum. 4) Simulate in Matlab this random walk evaporation problem. Your simulation should allow molecules that can move to a nearby site to do so, prevent molecules that cannot move from doing so, and should allow a gravitational tendency to move down more often than up. Code outline follows: NumRows 25; NumCols = 25; FracFull 0.6; gravity 0; plotevery 100; TheReactor = zeros(NumRows,NumCols); TheReactor(round((1-FracFull)*NumRows)end,:)-1 figure(gcf) clf for ii 1:1000000 thepixel choose a pixel at random'); if (thepixel is occupied) if ii/plotevery-round(ii/plotevery) imshow(-TheReactor,'InitialMagnification',2000); en therandstep = (choose a random step in x and y'); ('deal with any random steps from thepixel are outside of the reactor"); ('determine whether the random step from thepixel is already occupied); (if it is NOT occupied the occupy it, and liberate thepixel location); end end 1) Molecular motions can be described by random walks 2) The state that nature chooses is based on maximizing entropy (and so minimizing Gibbs free energy) 3) Evaporation-condensation is an example of an equilibrium that forms at a Gibbs minimum. 4) Simulate in Matlab this random walk evaporation problem. Your simulation should allow molecules that can move to a nearby site to do so, prevent molecules that cannot move from doing so, and should allow a gravitational tendency to move down more often than up. Code outline follows: NumRows 25; NumCols = 25; FracFull 0.6; gravity 0; plotevery 100; TheReactor = zeros(NumRows,NumCols); TheReactor(round((1-FracFull)*NumRows)end,:)-1 figure(gcf) clf for ii 1:1000000 thepixel choose a pixel at random'); if (thepixel is occupied) if ii/plotevery-round(ii/plotevery) imshow(-TheReactor,'InitialMagnification',2000); en therandstep = (choose a random step in x and y'); ('deal with any random steps from thepixel are outside of the reactor"); ('determine whether the random step from thepixel is already occupied); (if it is NOT occupied the occupy it, and liberate thepixel location); end end