Question

Classify two types of igneous rocks on the basis of silica

Answer 1

Acid rocks have over 65% silica, intermediate rocks have 55-65% silica, and basic rocks have 45-55% silica.Igneous rock forms when magma(molten rock) cools and solidifies. Extrusive igneous rocks are those formed when magma reaches the surface (at which point it is called lava), cooling and solidifying quickly.