Advertisements
Advertisements
प्रश्न
How would you confirm that a colourless liquid given to your is pure water ?
Advertisements
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.
APPEARS IN
संबंधित प्रश्न
Name the processes involved in two cases.
A kind of matter which can sublime is
What are the conditions for 'something' to be called 'matter'?
What is the scientific name of particles which make up mater?
Which of the following statements are true for pure substances ?
- pure substances contain only one kind of particles
- pure substances may be compounds or mixtures
- pure substances have the same composition throughout
- pure substances can be exemplified by all elements other than nickel
Which of the following does not have a fixed melting point/boiling point ?
Choose one term from the following which includes the other three :
aerosol, emulsion, colloid, sol
What is meant by the concentration of a solution ?
Which technique can be used to detect and identify traces of poison present in the stomach wash of a person ?
Write a method to separate a mixture of sand and potash alum.
Describe a method for separating a mixture of iron filings and sulphur powder other than that by using a magnet.
Explain how, impure copper sulphate can be purified by crystallisation.
How can you obtain pure water from a salt-water mixture (or salt-solution) ? Draw a neat and labelled diagram of the apparatus you would use to obtain pure water from a salt-water mixture (or salt-solution).
Which of the following mixture cannot be separated by using water as the solvent ?
Explain the meaning of the term matter with special reference to the term ‘substance’.
All the matter made of ______.
The most reactive metal is ______.
Complete the following table:
| S.No. | CELSIUS | KELVIN |
| 1. | 90°C | 363 K |
| 2. | ______ | 283 K |
| 3. | 63 °C | ______ |
| 4. | 250°C | ______ |
| 5. | ______ | 303 K |
Solids do not flow.
Define the term matter.
