Question

Multiple choice questions (i) Which one of the following minerals is formed by decomposition of rocks, leaving a residual mass of weathered material? (a) coal (b) bauxite (c) gold (d) zinc (ii) Koderma, in Jharkhand is the leading producer of which one of the following minerals? (a) bauxite (b) mica (c) iron ore (d) copper (iii) Minerals are deposited and accumulated in the stratas of which of the following rocks? (a) sedimentary rocks (b) metamorphic rocks (c) igneous rocks (d) none of the above (iv) Which one of the following minerals is contained in the Monazite sand? (a) oil (b) uranium (c) thorium (d) coal

Answer 1

Answer:

1.b)bauxite.2.(b)mica.3(a)sedimentary rocks.4(c)thorium

Answer 2

(i) (b) bauxite: bauxite is the major source of aluminium. The aluminium that we use in our daily life is extracted from bauxite which contains around 35 to 40% of aluminium. Australia is the biggest producer of bauxite in the world.

(ii) (b) mica: mica is a shimmery substance found in abundance in Jharkhand region of India. It is widely used for its shimmery properties in makeup products.

(iii) (a) sedimentary rocks: These rocks are formed by deposition of layers of sediments and that is the reason why these rocks often are found with distinctive layers.

(iv) (c) thorium: monazite sand is the most important ore for obtaining thorium. This sand has an abundance of helium in it due to alpha decay of thorium.