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Question
What is a colloid ? Give two examples of colloids (or colloidal solutions)
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Solution
Colloidal solution is a heterogeneous mixture, wherein the particle size of the substance is intermediate of true solution and suspension, i.e., between 1 nm to 100 nm. Like true solutions, colloidal particles are small enough and cannot be seen through naked eye. They easily pass through the filter paper. However, these particles are big enough to be blocked by parchment paper or animal membrane.
Example: Starch solution, ink
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