NCS Chemistry Notes- Rocks

About igneous, metamorphic and sedimentary rocks etc.

Sedimentary rocks…

Form over millions of years

Are crystals a rock? Are sedimentary, igneous and metamorphic?

No, crystals aren’t. But, sedimentary, igneous and metamorphic are.

What is the hardest type of rock?

Igneous

What rock contains bands of crystals?

Metamorphic

What rocks tend to be crumbly?

sedimentary

Basalt is what type of rock?

Igneous

Sedimentary rocks may contain fossils

Is limestone a metamorphic rock?

No!

Does magma cool down and crystalise in order to form sedimentary rocks?

No

metamorphic rocks are formed

by high temperature and pressure on existing rocks

are sedimentary rocks softer/harder than igneous rocks?

Sedimentary rocks are SOFTER than igneous rocks

At least ?% of any limestone rock is what substance?

At least 50% of any limestone rock is calcium carbonate

Slate is what type of rock

slate is a metamorphic rock

What are fossils?

They are the remains of dead plants and animals that have been buried for millions of years.

Fossils are most likely to be found in what type of rock?

Sedimentary rocks

Fossils are never found in what type of rock?

They are never found in igneous rocks.

Crystals that form slower are generally __ than crystals that form quicker?

Crystals that form slower are generally LARGER than crystal that forms quicker.larger

Limestone is what type of rock?

Limestone is a sedimentary rock

What is weathering?

Weathering is the process of breaking large rocks into smaller pieces of rocks.

What does physical weathering involve?

Temperature

What does freeze-thaw weathering involve?

Water

When water freezes, it…

expands.

Which is a type of rock that is not attacked by acid rain?

Granite

1. When molten rock cools it forms igneous rocks. Rocks formed slowly below the surface of the Earth are called intrusive igneous rocks. Those formed more quickly at Earth's surface in contact with the air or with water are called extrusive igneous rocks. At the Earth's surface rocks are weathered. Weathering breaks down big rocks into smaller pieces.

1. Sedimentary rocks are formed from layers of sediment laid down in lakes or seas. As more layers of sediment build up, water is gradually squeezed out of the sediments. Eventually the rock grains become cemented together to form sedimentary rocks. These rocks may contain fossils.

1. High temperatures and pressures can turn existing sedimentary or igneous rocks into metamorphic rocks. Examples of metamorphic rocks include schist, gneiss and slate.

1. Sedimentary rocks like limestone are often porous. Water substance can enter into the gaps between the grains in limestone. The substance forms ice when it freezes. Water can enter the gaps, and as it freezes, it expands (water expands when frozen). This process could eventually breaks up the rock.

1. Process of how granite can be changed into a sedimentary rock.

Granite is weathered.

The weathered rock pieces are transported by rivers.

The river flows more slowly as it reaches the sea.

The river deposits the sediment.

Layers of sediment build up.

The water is squeezed out of the sediment and the rock grains become cemented together.