The word volcano originally comes from the name of the Roman god of fire, Vulcan.
Most people think of volcanoes as large shaped mountains. But there are other kinds of volcanoes – Wide Plateaus, fissure vents (Cracks where lava emerges), Bulging dome shapes.
Common volcanic gases include –
water vapor H2O
carbon dioxide CO2
sulfur dioxide SO2
Hydrogen fluoride HF
Hydrogen chloride HCL
Hydrogen sulfide H2S
Liquid rock is called magma when it is under the earth’s surface and lava after it comes out.
Did you know – 75% of the volcanoes on the Earth are found in an area in the Pacific Ocean known as the Ring of Fire. The biggest known volcano in our solar system is on Mars– called Olympus Mons. Its mouth is 600 kms wide with an elevation of 21 kms.
Pumice is a unique volcanic rock (igneous) that can float in water.
It can also be used as an abrasive and is sometimes used in beauty salons for removing dry skin.
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