The level of toxins in the fish's cell is equivalent to the level of toxins in the water. Therefore, in order to reduce the toxins further, we should replace the now contaminated water with clean water. After the level of toxins in the fish's cell stops reducing, we replace the water with clean water once again.
Atoms combine<span> by forming chemical bonds</span>
False. At equilibrium, the rate of forward reaction is equal to the rate of backward reaction. The net concentration of both products and reactants won't change, but the reactions still take place.
I think it is decomposition because it processes in which chemical species break up into simpler parts.