Change the boundary condition at the top boundary: particle that are being reflected there change and become a different type: Particle 2. all the particles are molecules. can you also implement a chemical reaction of the particles within the box: when particle 1 and particle 3 collide with one another in the box, they react to particle 2 and particle 4. Make suggestions how to implement the collision and reaction probability in the code. Is it possible to have a rate constant as starting parameters (in M-1 s-1)? Prior to this work, I had no experience with stochastic simulations of chemical reactions or Python coding (though I have recently used ChatGPT for random walk modeling ). Consequently, initially I did not know how to calculate and implement a collision radius for [Ru(bpy and [Ru(bpy ions an essential factor for simulating annihilation reactions (unlike in finite element simulations, where the reaction rate constant suffices without explicit collisions). To address this challenge, I asked ChatGPT to explain the concept of collision radius and integrate it into the code. The resulting explanation and code are provided in full in the Appendix. This interaction highlights utility beyond programming: the model demonstrates a solid understanding of the underlying physics and chemistry and directly implements it in the script.