Explain what is observed (i) when a beam of light is passed through a colloidal sol. (ii) an electrolyte, NaCl is added to hydrated ferric oxide sol. (iii) electric current is passed through a colloidal sol?
Answers
The answers are following –
(i) when a beam of light is passed through a colloidal sol, then the scattering of light can be observed. It is called as Tyndall effect.
(ii) When NaCl is added to the ferric oxide sol, it dissociates into CL- and Na+ ions. As the particles of the ferric oxide solution are positively charged, they are coagulated in presence of the Cl- ions.
(iii) If an electric current is passed through a colloidal sol, the particles get charged either positively or negatively.
Answer:
(i)When a beam of light is passed through a colloidal solution, then scattering of light is observed. This is known as the Tyndall effect. This scattering of light illuminates the path of the beam in the colloidal solution.
(ii) An electrolyte, NaCl is added to hydrated ferric oxide sol. ... Particles of ferric oxide sol are positively charged. Thus, they get coagulated in the presence of negatively charged Cl- ions.
(iii) The colloidal particles are charged and carry either a positive or negative charge.
Explanation: