CUET · CHEMISTRY · PYQ PAPER 2023
Answer the question on the basis of passage given below :
A colloid is a heterogeneous system in which a substance is dispersed (dispersed phase) as fine particles in another substance called dispersion medium.
Their particle size is intermediate between that of pure solutions (less than 1 nm) and suspensions (greater than 1000 nm). They are known for interesting properties such as enormous surface area, Tyndall effect, Brownian motion etc.
They are widely used in industries and day to day life.
Some prominent uses of colloids are those in smoke precipitators, purification of water, medicines, cleansers etc.
Which of the following electrolyte exhibits maximum flocculating power in the coagulation of a positive metal hydroxide sol?
- A KCl
- B \(\text{K}_2\text{SO}_4\)
- C \(\text{K}_3\text{PO}_4\)
- D \(\text{K}_4\text{[Fe(CN)}_6\text{]}\)
Answer & Solution
Correct Answer
(D) \(\text{K}_4\text{[Fe(CN)}_6\text{]}\)
Step-by-step Solution
Detailed explanation
For a positive sol, flocculating power \( \propto \) |charge of anion|. Anions and their charges: \( \text{Cl}^- \) (-1), \( \text{SO}_4^{2-} \) (-2), \( \text{PO}_4^{3-} \) (-3), \( \text{[Fe(CN)}_6\text{]}^{4-} \) (-4). Maximum flocculating power is for…
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