KEY Chapter 9 Review for Test. You will work with a ... Question 2 page 278. Which type of rocks are produced by volcanic eruptions? ANS. Igneous rock...
KEY Chapter 9 Review for Test You will work with a partner to prepare for the test. Question 1 page 285 When/how do metamorphic rocks form? Key processes to remember to tell how metamorphic rocks are formed are heat and pressure, but not melting. It takes place millions of years. The process usually occurs thousands of meters below Earth’s surface where temperature and pressure are high. These rocks “morph”- Look different, recrystallize, and might be chemically changed.
Question 2 page 278 Which type of rocks are produced by volcanic eruptions? ANS. Igneous rock Volcanoes erupt and shoot lava and ash. Large cracks in the crust can open up and lava flow occurs. Exposure to air causes fast cooling in the formation of these rocks.
Question 3 page 272 Your teacher gives you two clear minerals. What quick test could you do in order to determine which is halite and which is calcite? ANS. Dilute HCl (hydrochloric acid) will fizz/react when it comes in contact with calcite and not the halite. The calcite will produce a double
image if looked through. mineral halite.
If it is salty it is the
Question 4 page 272 Would you expect to find a well-preserved dinosaur bone in a metamorphic rock like schist? Explain. ANS. No. The high heat, pressure, and chemical changes that form metamorphic rocks will likely destroy dinosaur bones. Question 5 p. 281-282 How are sedimentary rocks formed? ANS. Sand, pebbles, sediments are dropped and deposited by wind, ice, gravity or water. Sediments collect in layers as they are compacted (squeezed) and cemented together over thousands to millions of years. Some sedimentary rocks form when seaweed, geysers, hot springs, or salty lakes, loaded with dissolved minerals, evaporates. Organic sedimentary rock forms from the piling up and compressing of once living matter. Question 6 p. 272 How can you test the hardness of a mineral? Conduct a hardness test by finding out what minerals scratch the other. If can scratch another mineral, it is the hardest.
Question 7 pages 271-272 Identify 2 properties of minerals that you feel are most reliable an in identifying minerals and 2 properties that you feel are least reliable in identifying minerals. Justify (give reasons for) your answer. ANS. Hardness and streak are more useful than some other characteristics. You can conduct a hardness test to see which mineral scratches the other. Streak is more useful than looking at the color of the mineral because different minerals can be similar colors, and although minerals might be the same color, the streak they make might be different. Color can fool you. Question 8 p 287 What processes can change existing rocks into sediment? Existing rock can be changed through weathering and erosion. Question 9 p. 284-285 Which type of rock would you expect to find deep in earth’s crust? Why? Metamorphic rocks will likely be found deep within the earth’s crust. Pressure and temperature in the lower crust of the earth are high. Question 10 page 270 What is the difference between cleavage and fracture in minerals? ANS Minerals that breaks by splitting into pieces with smooth, regular planes, or thin sheets that reflect light is cleavage. ANS. Fracture minerals break into pieces with jagged or rough edges.
Question 11 P. 285 How can a metamorphic rock be changed into an igneous rock? ANS. High heat and cooling of the rock will change metamorphic rock into igneous rock. Question 12 p. 279 You are given a rock sample that formed from magma and has large crystals. What type of rock is it? How do you know? ANS. Intrusive Igneous rock The hot mass of rock material cooling slowly over millions of years. The cooling is so slow that magma have time to form large crystals. Question 13 Page 283 You are given a rock sample that has many fossils of sea organisms in it and fizzes when in contact with acid. What type of rock is it most likely? How do you know? ANS. Fossiliferous limestone is composed almost entirely of calcite and will produce a vigorous fizz with a drop of hydrochloric acid. Question 14 You are given a rock sample that formed from minerals that were heated and squeezed together. It has distinct bands of minerals in parallel layers. What type of rock is it most likely? How do you know? Ans. A rock sample that formed from minerals that were heated and squeezed together are metamorphic rocks. Because they have visible layers they are foliated metamorphic rocks .
