Flashcards
year 8 mid-term science test mlshs
Cards in this deck (56)
- 1How deep is the crust?The crust is 5-70km deep.
- 2Which is the thin part of the crust?The oceanic crust.
- 3Which is the thicker part of the crust?The continental crust.
- 4Which is the denser part of the crust?The oceanic crust.
- 5Which is the less dense part of the crust?The continental crust.
- 6What is the oceanic crust composed of?Mafic iron magnesium silicate igneous rocks, such as basalt
- 7What is the continental crust composed of?Felsic sodium potassium aluminium silicate rocks, such as granite
- 8Where is the oceanic crust located?Under oceans.
- 9How deep is the mantle?2,890km deep.
- 10What are the mantle's two parts, and what are they separated by?The upper and lower mantle, the transition zone.
- 11How deep is the transition zone?410 - 660km.
- 12What is the mantle composed of?The mantle is composed of silicate rocks that are rich in iron and magnesium (same as the crust).
- 13How deep is the outer core?2000km.
- 14Is the outer core liquid, solid or gas?Liquid.
- 15What is the outer core made of?Iron and nickel with trace amounts of other elements.
- 16How deep is the inner core?1300km deep.
- 17Is the inner core gas, solid or liquid?It is solid.
- 18What is the inner core made of?Iron, nickel and sulphur with other trace elements
- 19What are rocks made of?A vast range of different minerals.
- 20Do all rocks have similar structures?No. They are very inconsistent in their structure.
- 21What are rocks' three groups?Igneous rocks, sedimentary rocks and metamorphic rocks.
- 22Rank the three rock groups in order of prevalence.1. Igneous rocks
2. Metamorphic rocks
3. Sedimentary rocks - 23What are minerals?Solid substances that occur naturally.
- 24What are minerals made of?They can be made of a single element, or they can be made from compounds (multiple elements).
- 25What are the five criteria for categorising a substance as a mineral?1. naturally occurring.
2. solid.
3. inorganic.
4. organised internal structure.
5. fixed chemical structure. - 26What are elements?Elements are the basic unit of all matter and are the building blocks of our earth.
- 27How many naturally occurring elements are there?92
- 28What are the two most abundant elements in the crust?Oxygen and Silicon
- 29Summarise the difference between rocks, minerals and elements.Rocks are composed of minerals and minerals are composed of elements.
- 30What is used to determined hardness in minerals?The Mohs scale.
- 31What is the least hard mineral and the most hard mineral on the Mohs scale?Talc - least and Diamond - most.
- 32What does cleavage mean in the context of minerals?Cleavage means the way a mineral breaks when it is dropped, struck etc.
- 33What is lustre in the context of minerals?Lustre means the quality and intensity of light reflected from the surface of a mineral.
- 34Why can lustre sometimes be difficult to observe?Because it must be viewed first-hand, and cannot be demonstrated through photography/video.
- 35What does streak mean in minerals?Streak means the colour that a mineral leaves behind when it scratches a surface, usually an unglazed white porcelain plate.
- 36How should you describe colour in minerals?With primary/simple colours e.g. 'dull reddish-brown', 'pale greenish-blue'. Avoid colour variants such as beige, mauve etc. because these are largely subjective.
- 37What are the characteristics of igneous rocks?Crystal size, and texture.
- 38How are igneous rocks formed?They are formed from the solidification of magma and/or lava.
- 39What is the difference between lava and magma?Lava is molten rock on/above the earth's surface and magma is the opposite - molten rock below the earth's surface.
- 40How are igneous rocks classified?According to their mineral/chemical composition, as felsic, intermediate, mafic and ultramafic.
- 41What are the two types of igneous rocksintrusive (formed under the earth's surface) and extrusive (formed above the earth's surface)
- 42How does cooling rate affect crystal size?Instrusive minerals have larger crystals, because they are formed by magma underneath the earth's surface, which take much longer to form than extrusive rocks that form from magma ABOVE the earth's surface.
- 43What are some similarities between intrusive and extrusive igenous rocks?Both cool from magma
Are both rocks
Both have minerals/crystals - 44What are some differences between intrusive and extrusive igneous rocks?Intrusive rocks are formed by magma beneath the earth's surface and thus have larger crystals due to the slow cooling rate while extrusive rocks are formed by lava above the earth's surface and thus have smaller crystals due to the rapid cooling rate.
- 45What are the three types of sedimentary rocks?Clastic (formed from previous rocks' fragments), biological (formed from organic material) and chemical (formed from mineral crystals and other elements that have been dissolved out of water)
- 46How are sedimentary rocks formed?They are formed when sediment is deposited out of air, ice, wind, gravity or water.
- 47What is weathering, and what are its two types?Weathering is the process by which rocks break down, and its two types are physical and chemical.
- 48What are the types of physical weathering?The action of water, ice, wind and plants.
- 49What are the types of chemical weathering?The action of gases and the action of acids.
- 50What is erosion?Erosion is when smaller rocks are moved by natural factors, such as water, gravity and wind.
- 51What is the difference between weathering and erosion?Weathering occurs in place whereas erosion involves movement to a new location.
- 52What can sedimentary rocks be used for?Construction or building materials, ornaments or fuel
- 53How are metamorphic rocks formed?They are created by the physical or chemical alteration by heat and pressure of an existing igneous or sedimentary material into a denser form.
- 54How are metamorphic rocks classified?They are classified on the basis of texture and mineral compositions, etc
- 55There are two different types of metamorphic rocks: name them.foliated and non-foliated
- 56What are some uses of metamorphic rocks?Building materials, decorations and other household items such as toothpaste.