EVERYDAY SCIENCE

Detailed explanation-1: -Extrusive Igneous Rocks: These are the rocks that form at erupting volcanoes and oozing fissures. The magma, called lava when molten rock erupts on the surface, cools and solidifies almost instantly when it is exposed to the relatively cool temperature of the atmosphere.

Detailed explanation-2: -Extrusive igneous rocks are also termed volcanic rocks-named for Vulcan, the Roman god of fire. Volcanic rocks have generally smaller crystal size and usually have a very-fine-grained or glassy groundmass that formed due to rapid cooling at the time of eruption.

Detailed explanation-3: -Basalt, tuff, pumice are examples of extrusive igneous rock.

Detailed explanation-4: -Answer: The molten lava comes out of volcanoes, reaches the earth’s surface and cools down rapidly to become a solid piece of rock. This is how extrusive rocks are formed. For example, basalt. When the molten lava solidifies deep inside the earth’s crust, the rocks so formed are called intrusive rocks.