B4.6 Diffusion

Question 1

Define diffusion

Answer 1

The spreading of the particles of a gas or a substance in solution, resulting in a net movement from a region of high concentration to a region of lower concentration . The bigger the difference in concentration, the faster the diffusion happens.

Question 2

Name two gases that enter and leave by diffusion

Answer 2

1. Oxygen

2. Carbon dioxide

Question 3

Name two ways substances can diffuse as.

Answer 3

1. As gases

2. As dissolved particles in solution

Question 4

How do particles pass through to get into a cell?

Answer 4

Through the cell membrane

Question 5

The process of diffusion does not use energy. Why?

Answer 5

Because the molecules move spontaneously from regions of high concentration to regions of low concentration

Question 6

Why does diffusion occur?

Answer 6

Because of constant random movement of particles in solution constantly move. Move from high to low concentration, giving a net movement.

(Rate of diffusion varies)

Question 7

Explain the three factors that affecr the rate of diffusion.

Answer 7

1. Distance- shorter the distance, the quicker the particles will diffuse.
2. Concentration gradient- greater the difference in concentration, the faster the rate of diffusion.
3. Surface area- greater the surface area that the particles have to diffuse across, the quicker the rate of diffusion.