Page 117 - Biology - XII

Q3. The phenomenon of scattering light by dispersed particles in a colloidal system is called
(a) brownian movement (b) cataphoresis

(c) tyndall eff ect (d) electrophoresis
Q4. Emulsions lack stability which can be gained by adding
(a) water (b) emulsifi er
(c) soap (d) both (b) and (c)

Q5. Electrophoresis is
(a) movement of electrons

(b) movement under infl uence of electric fi eld
(c) movement of particles to poles in electric fi eld
(d) all of these
Answer key

1. (c), 2. (d), 3. (c), 4. (d), 5. (c)

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