1.
Which one of the following statements concerning minerals is NOT true?
Correct Answer
C. Organic
Explanation
The statement "organic" is not true when it comes to minerals. Minerals are inorganic substances that are naturally occurring, have a definite chemical structure, are solid, and are formed of atoms. "Organic" refers to compounds that contain carbon and are derived from living organisms, which does not apply to minerals.
2.
The property which is a measure of the resistance of a mineral to abrasion or scratching is ____________.
Correct Answer
A. Hardness
Explanation
Hardness is a measure of a mineral's resistance to abrasion or scratching. It determines how easily a mineral can be scratched by other materials. Minerals with a higher hardness will scratch minerals with a lower hardness. Cleavage refers to the way a mineral breaks along flat surfaces, crystal form refers to the geometric shape of a mineral's crystal structure, streak refers to the color of a mineral's powder, and fracture refers to the way a mineral breaks along irregular surfaces.
3.
The basic building block of the silicate minerals ____________.
Correct Answer
A. Contains one silicon atom and four oxygen atoms
Explanation
Silicate minerals are composed of silicon (Si) and oxygen (O) atoms. The basic building block of these minerals consists of one silicon atom bonded to four oxygen atoms. This arrangement forms a tetrahedral structure, with the silicon atom at the center and the four oxygen atoms surrounding it. This tetrahedral structure is the fundamental unit that repeats to form the silicate mineral. Therefore, the correct answer is "contains one silicon atom and four oxygen atoms."
4.
Which one of the following is NOT one of the eight most abundant elements in Earth's continental crust?
Correct Answer
A. Hydrogen
Explanation
Hydrogen is not one of the eight most abundant elements in Earth's continental crust. This is because hydrogen is a light element and tends to escape from the Earth's atmosphere due to its low molecular weight. Therefore, it is found in much smaller quantities compared to elements like aluminum, oxygen, calcium, and iron, which are more abundant in the continental crust.
5.
Most silicate minerals form from ____________.
Correct Answer
C. Molten rock
Explanation
Silicate minerals are formed from molten rock, also known as magma. When magma cools and solidifies, it forms different types of silicate minerals, such as quartz, feldspar, and mica. These minerals make up a large portion of the Earth's crust and are commonly found in igneous rocks. The cooling process allows the atoms and molecules in the molten rock to arrange themselves into a crystalline structure, giving rise to the formation of silicate minerals.
6.
Atoms of the same element possess the same number of ____________.
Correct Answer
B. Protons
Explanation
Atoms of the same element possess the same number of protons. Protons are positively charged particles found in the nucleus of an atom. The number of protons determines the atomic number of an element and distinguishes it from other elements. Therefore, all atoms of a particular element have the same number of protons, regardless of the number of neutrons or electrons they may have.
7.
The scale used by geologists to measure the hardness of a mineral is called the __________ scale.
Correct Answer
C. Mohs
Explanation
The correct answer is Mohs. The Mohs scale is a scale used by geologists to measure the hardness of minerals. It was developed by Friedrich Mohs in 1812 and is based on the ability of one mineral to scratch another. The scale ranges from 1 (the softest mineral, talc) to 10 (the hardest mineral, diamond).
8.
Oxygen comprises about _________ percent by weight of Earth's continental crust.
Correct Answer
A. 47
Explanation
Oxygen comprises about 47 percent by weight of Earth's continental crust. This means that almost half of the weight of the continental crust is made up of oxygen. Oxygen is a highly abundant element and is a major component of many minerals that make up the Earth's crust, such as silicates. This high percentage of oxygen in the continental crust is important for various geological processes and the overall composition of the Earth's surface.
9.
Igneous rocks that contain the last minerals to crystallize from magma and consist mainly of feldspars and quartz are said to have a ____________ composition.
Correct Answer
D. Granitic
Explanation
Igneous rocks that contain the last minerals to crystallize from magma and consist mainly of feldspars and quartz are said to have a granitic composition. This composition refers to rocks that are rich in silica and aluminum, which are the main components of feldspars and quartz. Granitic rocks tend to be light in color and have a coarse-grained texture. They are commonly found in continental crust and are associated with the formation of mountains.
10.
Fossils found in sedimentary rocks can be used to ____________.
Correct Answer
D. All of the above
Explanation
Fossils found in sedimentary rocks can be used to interpret past environments because they provide evidence of the types of organisms that lived in those environments. They can also indicate certain periods of time because different organisms existed during different geological periods. Additionally, fossils can be used to match rocks of the same age that are found at different places, as the presence of the same fossils in different locations suggests that the rocks were formed during the same time period. Therefore, the correct answer is all of the above.
11.
The surface process that slowly disintegrates and decomposes rock is called ____________.
Correct Answer
B. Weathering
Explanation
Weathering is the correct answer because it refers to the surface process that gradually breaks down and decomposes rock over time. This process can occur through various mechanisms such as physical weathering (e.g. freeze-thaw cycles, abrasion), chemical weathering (e.g. oxidation, dissolution), and biological weathering (e.g. root growth, burrowing organisms). Weathering plays a crucial role in the formation of soil and the shaping of landscapes, ultimately leading to the creation of sedimentary rocks.
12.
Which one of the following is NOT an agent of metamorphism?
Correct Answer
C. Lithification
Explanation
Lithification is not an agent of metamorphism because it refers to the process of compacting and cementing of sediments to form sedimentary rocks, rather than the alteration of existing rocks through heat, pressure, or chemically active fluids. Metamorphism is primarily driven by these three agents, which cause changes in the mineral composition and texture of rocks, while lithification is a separate process involved in the formation of sedimentary rocks.
13.
The great majority of rocks exposed at Earth's surface are of which type?
Correct Answer
B. Sedimentary rocks
Explanation
The great majority of rocks exposed at Earth's surface are sedimentary rocks. This is because sedimentary rocks are formed through the accumulation and compaction of sediments such as sand, mud, and organic matter over time. These sediments are typically deposited in layers on the Earth's surface, and as more and more layers accumulate, they become compacted and cemented together to form sedimentary rocks. Igneous rocks, on the other hand, are formed from the solidification of molten material, and metamorphic rocks are formed from the transformation of pre-existing rocks under high pressure and temperature conditions. However, these types of rocks are not as common at the Earth's surface as sedimentary rocks.
14.
Molten material found inside Earth is called ____________.
Correct Answer
B. Magma
Explanation
Magma is the correct answer because it refers to the molten material found inside the Earth. Magma is a mixture of molten rock, minerals, and gases that is located beneath the Earth's surface. It is typically formed through the melting of rocks due to high temperatures and pressure. Magma can eventually reach the Earth's surface and be called lava once it erupts from a volcano.
15.
Why can two igneous rocks have the same minerals but different names?
Correct Answer
C. They may have different textures.
Explanation
Two igneous rocks can have the same minerals but different names because they may have different textures. Texture refers to the size, shape, and arrangement of the mineral grains within a rock. Different cooling rates or conditions during the formation of the rocks can result in different textures, even if they have the same mineral composition. Therefore, rocks with the same minerals but different textures can be given different names to reflect their distinct characteristics.
16.
The most important agent of chemical weathering is ____________.
Correct Answer
C. Water
Explanation
Water is the most important agent of chemical weathering because it can dissolve minerals and rocks, leading to their breakdown and alteration. Water can react with certain minerals, causing them to undergo chemical reactions and break down into different substances. Additionally, water can also facilitate the transportation of dissolved minerals, allowing them to be carried away from their original location. Overall, the abundance and properties of water make it a powerful force in the process of chemical weathering.
17.
The single most characteristic feature of sedimentary rocks are
Correct Answer
B. Strata
Explanation
Sedimentary rocks are formed through the accumulation and compaction of sediments over time. The most characteristic feature of these rocks is the presence of distinct layers or strata. These layers are formed as sediments settle and are deposited in different environments, such as rivers, lakes, or oceans. Each layer represents a different period of deposition and can provide valuable information about the Earth's history. Therefore, the presence of strata is a key characteristic that distinguishes sedimentary rocks from other types of rocks.
18.
Detrital sedimentary rocks are subdivided according to ____________.
Correct Answer
B. Particle size
Explanation
Detrital sedimentary rocks are subdivided according to particle size. This is because the size of the particles in these rocks can provide important information about the environment in which they were deposited. Larger particles, such as gravel and sand, are typically found in high-energy environments like rivers and beaches, while smaller particles, such as silt and clay, are often found in low-energy environments like lakes and swamps. By categorizing these rocks based on particle size, geologists can gain insights into the depositional history and conditions of the rock formation.
19.
Accumulation of silts and clays, and eventually the rocks siltstone and shale, is generally best associated with which one of the following environments?
Correct Answer
D. Quiet swamp water
Explanation
The accumulation of silts and clays, which eventually form rocks like siltstone and shale, is typically best associated with quiet swamp water. In this environment, the water is slow-moving or stagnant, allowing fine particles to settle and accumulate over time. The lack of strong currents prevents the sediments from being easily transported elsewhere, leading to their accumulation and eventual lithification into sedimentary rocks.
20.
Which one of the following is NOT a primary element found in magma?
Correct Answer
D. Carbon
Explanation
Carbon is not a primary element found in magma. Magma is primarily composed of silicon, oxygen, iron, and aluminum. Carbon is not typically found in magma because it has a higher tendency to form compounds with oxygen, such as carbon dioxide, rather than remaining in its elemental form.