Advertisements
Advertisements
प्रश्न
Explain how, nitrogen , oxygen and argon gases are separated from air.
Advertisements
उत्तर
Nitrogen, oxygen and argon are separated from air by fractional distillation. Following are the steps followed to separate these gases from air:
- Air is first filtered to remove the dust particles, spores etc. Subsequently water vapours and carbon dioxide are removed.
- Air is subjected to high pressure and then cooled. This air is then allowed to expand in a chamber which causes further cooling of the air.
- This process is repeated to cool the air further. Ultimately, the air becomes so cold that it turns into a liquid.
- This liquid air is then fed into a fractionating column from its bottom end and is cooled slowly.
- Liquid nitrogen boils off first to nitrogen gas as the boiling point of nitrogen is lowest at -196°C.
- Liquid argon boils off at a boiling point of -186°C.
- Liquid oxygen boils off last as it has highest boiling point among all three (around -183°C).
Figure 84. Separation of the major gases of air.
APPEARS IN
संबंधित प्रश्न
Fill in the blank
All matter is made up of tiny particles called ______
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
What are the three groups into which all the elements can be divided ? Name two elements belonging to each group.
Iron powder and sulphur powder were mixed together and divided into two parts A and B. When part A was heated strongly over a burner, then a substance C was formed. The part B was, however, not heated at all. When dilute hydrochloric acid was added to substance C, then gas D was evolved and when dilute hydrochloric acid was added to part B then gas E was evolved.
- What type of substance is B ?
- What type of substance is C ?
- Name the gas (i) D, and (ii) E ?
- State one characteristic property of gas D.
- Write one test to identify gas E.
Define the emulsion. Give one example.
What is meant by the concentration of a solution ?
The solubility of ammonium chloride in water at various temperatures is given below :
| Temperature | : | 10°C | 20°C | 40°C | 60°C | 80°C |
| Solubility | : | 24 g | 37 g | 41 g | 55 g | 66 g |
What mass of ammonium chloride would be needed to make a saturated solution of ammonium chloride in fifty grams of water at 40°C ?
Name the process which can be used to recover salt from an aqueous salt solution.
Name the process you would use to separate a mixture of water and alcohol.
How is scrap iron separated from a heap of waste materials in factories?
With the help of a labelled diagram, describe the method of separating ammonium chloride from a mixture of ammonium chloride and common salt. Mention the difference in the properties of ammonium chloride and sodium chloride which has made this separation possible.
What's the solution?
We need to rub salt on a corncob, but only salt crystals are available.
Diffentiate between absorption and adsorption.
Stars including Sun are covered in ______.
You want to wear your favourite shirt to a party, but the problem is that it is still wet after a wash. What steps would you take to dry it faster?
Gases do not diffuse very easily.
Define the term matter.
Write a scientific reason.
Lemon sherbat has sweet, sour and salty taste and it can be poured in a glass.
Define the term matter.
