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Question
Explain why, osmosis can be considered to be a special kind of diffusion. Classify the following into
(i) osmosis, and (ii) diffusion :
- swelling up of a raisin on keeping in water
- spreading of virus on sneezing
- earthworm dying on coming in contact with common salt
- shrinking of grapes kept in thick sugar syrup
- preserving of pickles in salt
- spreading of smell of cake being baked in the kitchen
- aquatic animals using oxygen dissolved in water during respiration
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Solution
Osmosis is considered to be a special kind of diffusion because it takes place only through a semi-permeable membrane, which allows only solvent particles to pass through it.
- Osmosis: a, c, d and e
- Diffusion: b, f and g.
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