Advertisements
Advertisements
प्रश्न
What are stalgmites and stalactites? How are they formed?
Advertisements
उत्तर
In some limestone caves, conical pillar-like objects hang from the roof and some rise from the floor. These are formed by water containing dissolved calcium hydrogen carbonate continuously dropping from the cracks in the rocks. Release of pressure results in the conversion of some hydrogen carbonate to calcium carbonate.
Ca(HCO3)2 → CaCO3 + CO2 + H2O
This calcium carbonate little by little and slowly deposit on both roof and floor of the cave.
The conical pillar which grows downwards from the roof is called stalactite and the one which grows upward from the floor of the cave is called stalagmite.
These meet after a time. In a year, some grow less than even a centimetre, but some may be as tall as 100 cm.
CaCO3 + CO2 + H2O → Ca(HCO3)2
MgCO3 + CO2 + H2O → Mg(HCO3)2
If the water flows over beds of gypsum (CaSO4.2H2O), a little bit of gypsum gets dissolved in water and makes it hard.
APPEARS IN
संबंधित प्रश्न
What is metal activity series ?
Give one word for the following statement:
The harmful substances dissolved in water .
What is the effect of impurities present in the water on the melting point and boiling point of water?
What do you understand by soft water?
Name a ‘pure form’ and an,‘impure form’ of water in the natural state.
Fill in the blank:
Unpolluted water has _____ amount of dissolved oxygen.
What is meant by the term ‘offshore drilling’. State the main environmental effects of offshore drilling.
A jumbled word is given here. Write the correct form of the word.
CHARREGE
Why should we not throw used tea leaves into sink?
Think and suggest some ways to minimise waste and pollutants at their source, taking your home as an example.
