What influence on diffusion (i.e. temperature, pressure, concentration) would cause the curves for bags C and D, for example, to eventually to become horizontal (I.e. have a slope of 0?)

Answer 1

The curves for bags C and D would become horizontal, with a slope of 0, when the concentration gradient driving the diffusion process reaches equilibrium. This is because, in diffusion, molecules move from an area of higher concentration to one of lower concentration, aiming to balance out the concentration on both sides. When this balance (equilibrium) is achieved, there is no net movement of molecules across the membrane, so the diffusion rate stops, causing the slope of the diffusion curve to flatten.

1. Concentration gradient: when the concentration inside the bags (e.g., bags CCC and DDD) matches the concentration outside, the concentration gradient is zero, halting diffusion and flattening the curve.
2. Temperature: Higher temperatures increase the kinetic energy of molecules, causing them to move faster and reach equilibrium more quickly. Conversely, lower temperatures slow down the movement of molecules and extend the time required to reach a horizontal slope in the curve.
3. Pressure: if the pressure remains constant and diffusion continues solely due to the concentration gradient, the curve will still flatten at equilibrium.

Therefore, concentration gradient mot directly affects when the curve become horizontal. Whereas, temperature and pressure can influence the rate at which equilibrium is reached but not the flattening of the curve.