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प्रश्न
How would you confirm that a colourless liquid given to your is pure water ?
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उत्तर
You can boil it and if it starts boiling at 100⁰ C, it might be water. You can also check its reactivity with some metals such as sodium and potassium that react violently with water. The best way, to prove that it is pure water, is to do experiments to see if it has the same capabilities and chemical behaviour as water has.
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संबंधित प्रश्न
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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Name one solid, one liquid and one gaseous non-metal.
Name the property which allows metals to be hammered into thin sheets.
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Which of the following does not have a fixed melting point/boiling point ?
How will you differentiate between a suspension and a colloid ?
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Fill in the following blanks with suitable words :
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How will you separate camphor, common salt and iron nails from their mixture ?
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(b) Which method will you use to separate a mixture of B and C ?
(c) Name the liquids which would behave like (i) A (ii) B and (iii) C.
Liquids have ______.
Evaporation is always accompanied by ______ in temperature.
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