From which of the following types of rocks is Pumice derived?

Options :
  1. Aquifer rocks
  2. Volcanic rocks
  3. Coral rocks
  4. Sedimentary rocks

Answer and Explanation :-

Answer: Option 2


Pumice, called pumicite in its powdered or dust form, is a volcanic rock that consists of highly vesicular rough textured volcanic glass, which may or may not contain crystals. It is typically light coloured. Pumice is created when super-heated, highly pressurized rock is violently ejected from a volcano. The unusual foamy configuration of pumice happens because of simultaneous rapid cooling and rapid depressurization. The depressurization creates bubbles by lowering the solubility of gases (including water and CO2) that are dissolved in the lava, causing the gases to rapidly exsolve (like the bubbles of CO2 that appear when a carbonated drink is opened). The simultaneous cooling and depressurization freezes the bubbles in the matrix.

How do you rate this queston?  Very Easy  Easy  Average  Above Average  Tough

Previous Question : Which of the following chemical compounds are known as Quartz crystals, normally used in quartz cloc...

Next Question : Which of the following materials is used in nuclear reactors as a coolant?

Click here for free online test on General Science


 (Getemail alerts when others member replies)

If you don't know that God loves you, he does. He loves his creation. And you're his creation.
-Lacey Mosley