Chapter Mock Test
Total Marks:40
Duration:45 min
Total Questions:20
Difficulty:Mixed
Test Structure
- —Section A: 10 MCQs (1 mark each)
- —Section B: 6 Short Answer (3 marks each)
- —Section C: 2 Long Answer (5 marks each)
Before taking the test
- —Know the three layers of the Earth: Crust (5-35 km), Mantle (2900 km depth), Core (3500 km radius)
- —Remember the key acronyms: SIAL (Silica + Alumina = continental crust), SIMA (Silica + Magnesium = oceanic crust), NIFE (Nickel + Iron = core)
- —Distinguish between Extrusive (surface, rapid cooling, fine grains, Basalt) and Intrusive (deep inside, slow cooling, large grains, Granite) igneous rocks
- —Understand sedimentary rocks: formed from compressed sediments in layers, can contain fossils (e.g., Sandstone)
- —Know metamorphic transformations: Clay becomes Slate, Limestone becomes Marble (under heat and pressure)
- —Master the rock cycle: Magma cools into Igneous, which weathers into Sedimentary, which transforms into Metamorphic, which melts back to Magma
- —Remember why igneous rocks are called primary rocks - they form first and all other rocks derive from them
- —Only sedimentary rocks can contain fossils - other rock types involve processes that destroy organic remains
- —The Deccan Plateau is made of basalt (extrusive igneous rock) - a commonly asked fact
- —Understand the onion analogy: Earth has concentric layers just like an onion has layers
Key Concepts to Remember
Earth's Layers
Crust (5-35 km, SIAL/SIMA) → Mantle (2900 km depth) → Core (3500 km radius, NIFE)
Rock Types
Igneous (from magma) → Sedimentary (from sediments + layers + fossils) → Metamorphic (heat + pressure)
Igneous Rock Types
Extrusive (surface, rapid, fine-grained = Basalt) vs Intrusive (deep, slow, coarse-grained = Granite)
Metamorphic Changes
Clay → Slate (heat + pressure) | Limestone → Marble (heat + pressure)