(a) Spreading of particles from a region of high concentration to a region of low concentration.
(b) Bright specks of light in constant random motion are seen.
Smoke particles collide with air particles that are in constant motion which make them change their direction of motion and hence move randomly.
(c) (i) To give enough time for the salt to dissolve to prevent displacement of
water.
(ii) Particles of salt enter into spaces between larger water particles.
joseph rimiru answered the question on January 5, 2018 at 15:50
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