Explain what is observed (i) When a b | Class 12 Chemistry Chapter Surface Chemistry, Surface Chemistry NCERT Solutions

Question:

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?

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) When NaCl is added to ferric oxide sol, it dissociates to give Na+ and Cl-­ ions. 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. The dispersion medium carries an equal and opposite charge. This makes the whole system neutral. Under the influence of an electric current, the colloidal particles move towards the oppositely charged electrode. When they come in contact with the electrode, they lose their charge and coagulate.


Study Tips for Answering NCERT Questions:

NCERT questions are designed to test your understanding of the concepts and theories discussed in the chapter. Here are some tips to help you answer NCERT questions effectively:

  • Read the question carefully and focus on the core concept being asked.
  • Reference examples and data from the chapter when answering questions about Surface Chemistry.
  • Review previous year question papers to get an idea of how such questions may be framed in exams.
  • Practice answering questions within the time limit to improve your speed and accuracy.
  • Discuss your answers with your teachers or peers to get feedback and improve your understanding.

Comments

  • Ballu Bumper
  • 2019-09-14 17:16:29

Nice one


  • Gyan Ranjan
  • 2019-09-14 17:16:00

Nice one


  • manas
  • 2019-09-13 13:01:38

Answers should be short.


  • Aman singh
  • 2019-05-23 15:38:06

Awesome


  • Ankit
  • 2019-05-21 10:28:44

NYC answers


  • Ggbiy
  • 2019-03-11 12:36:09

Thank u


  • Swasti Mishra
  • 2019-03-10 09:24:47

Superb answer👍


  • Vivek
  • 2018-08-19 06:47:11

Kya aapka app nhi hai agar hai to pls mere no pe send Kare 7982939250


Comment(s) on this Question

Welcome to the NCERT Solutions for Class 12 Chemistry - Chapter . This page offers a step-by-step solution to the specific question from Excercise 2 , Question 15: Explain what is observed (i) When a beam of light is passed through a colloidal sol. (ii) An e....