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Question
What is diffusion? Give an example to illustrate it.
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Solution
Diffusion is the process of gradual mixing of two substances, kept in contact, by molecular motion.
Example:
If a jar of chlorine is opened in a large room, the odorous gas mixes with air and spreads to every part of the room. Although chlorine is heavier than air, it does not remain at the floor level but spreads throughout the room.
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