Quiz 2
Answer the following questions:
1. Atoms with the same atomic number but different mass numbers are called
A) molecules.
B) isotopes.
C) elements.
D) ions.
E) compounds.
2. In the illustration below, the part of the atom that has a negative charge is referred to as the
A)
B)
C)
D)
first electron energy level.
second electron energy level.
Both A and B are correct.
nucleus.
3. The mass number of an atom is
A) the number of protons and neutrons in the nucleus.
B) the number of protons in the nucleus.
C) the number of neutrons in the nucleus.
D) the number of electron energy levels.
E) the number of electrons in the outermost energy level.
4. One atom of a hypothetical element X has 27 neutrons while another has 29. This would
make the two atoms of the element
A) molecules.
B) compounds.
C) ions.
D) isotopes.
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5. What type of weak bond results from asymmetry in charge distribution?
A) covalent bond
B) metallic bond
C) ionic bond
D) Van der Waals bond
6. What type of bond forms the strongest chemical bonds and compounds that tend to be strong
with great hardness?
A) covalent bond
B) metallic bond
C) ionic bond
D) Van der Waals bond
7. The property of a mineral that relates how heavy it is for its size is referred to as
A) streak.
B) density.
C) hardness.
D) tenacity.
8. Which element is the most abundant in Earth's crust?
A) silicon
B) iron
C) calcium
D) oxygen
9. Which type of rocks have been altered by heat and pressure so that a new mineral assemblage
and rock fabric has developed?
A) Igneous rocks
B) Metamorphic rocks
C) Sedimentary rocks
D) None of the above answers are correct.
10. Granite and basal are what type of rocks?
A) Igneous rocks
B) Metamorphic rocks
C) Sedimentary rocks
D) None of the above answers are correct.
11. Which type of rocks are held together by naturally forming cement?
A) Igneous rocks
B) Metamorphic rocks
C) Sedimentary rocks
D) None of the above answers are correct.
Fill in the blank
12. An atom that has an excess positive or negative electrical charge caused by the loss or
addition of an electron is called a(n) ______.
ion.
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13. The mass number of an atom is the sum of the protons and ______.
neutrons
14. The four types of bonding that are important in minerals are ______, covalent, metallic, Van
der Waals.
ionic
15. The property of ______ is a mineral's resistance to scratching.
hardness
16. Some minerals break along specific directions of weakness in their crystal structures. This
property of a mineral to break in this predictable way is referred to as______.
cleavage
17. The _____ of a mineral is the color of the mineral when powdered, which is usually
accomplished in soft minerals by rubbing the sample against an unglazed porcelain plate.
streak
18. _____ and silicon are the two most common elements in Earth's crust.
Oxygen
19. The two most abundant mineral families of Earth's crust are the silicates and the _____.
oxides
20. Based on their origins, rocks can be divided into three distinct families: _______,
sedimentary and metamorphic.
igneous
Short Essay
21. There are 6 protons in the nucleus of a carbon atom. How many neutrons are there in carbon
12, carbon 13, and carbon 14, respectively?
Carbon 12- 6 neutrons
Carbon 13- 7 neutrons
Carbon 14- 8 neutrons
22. What is the difference between ionic and covalent bonding? Which type of bonding creates
compounds that tend to be relatively strong and hard?
Ionic bonding is when an atom transfers an electron to another, it has moderate strength
and hardness. Covalent bonding is the sharing of electrons these bonds are strong and
hard.
Covalent bonding create compounds which tend to be relatively strong and hard
(ex. diamond).
23. What is the difference between metallic and Van der Waals? Which type of bonding creates
compounds that tend to be relatively malleable and good conductors of electricity?
In metallic bonding the atoms of the metals are tightly packed where they can share
electrons among several atoms. The outermost electrons are loosely held which makes them
good conductors of electricity and heat.
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Van der Waals bonding is a weak bond that can easily be broken. One side of a neutral
molecule is slightly positive and the other side is slightly negative.
24. What are the four requirements necessary to classify a solid material as a mineral?
A mineral is a naturally formed, inorganic, solid, substance with a characteristic crystal
structure and a specific chemical composition.
25. Why is color an unreliable way to identify a mineral?
Color is an unreliable way to identify a mineral because many minerals may share the
same color and may look similar to one another judging on color only.
26. Two chemical elements make up 70 percent of Earth's crust by weight. What are the two
elements and what family of minerals do they form?
The two elements are silicon and oxygen. The family of minerals are silicate(silicon) and
oxide(oxygen).
27. What's the difference between a rock and a mineral?
Minerals are the building blocks of rocks where rocks are the sum of one or more minerals.
28. What are the three families of rocks? How does each of these families differ?
The three families of rocks are igneous, metamorphic, and sedimentary.
Igneous rocks are formed by cooling and solidification of molten rock.
Metamorphic rocks have been altered by exposure to high temperature, high pressure, or
both. These rocks may have been started as igneous or sedimentary.
Sedimentary rocks are formed under conditions of low pressure and low temperature near
the surface. These rocks consist largely of grains or clasts that were eroded from other
rocks.
29. The figure below illustrates bonding forming crystal structures of carbon. Indicate which
one is the structure of graphite and which diamond. Identify the types of bonding in each and
explain how the different bonding in the structures relates to the great difference in hardness
between the two minerals.
29. The figure below illustrates bonding forming crystal structures of carbon. Indicate which
one is the structure of graphite and which diamond. Identify the types of bonding in each and
explain how the different bonding in the structures relates to the great difference in hardness
between the two minerals.
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The figure on top shows covalent bonding which is the strongest chemical bonding. The
atoms are bonded in a tridimensional network that is very hard to break. The elements and
compounds with covalent bonds (such as diamond) tend to be strong and hard.
The figure on bottom shows that the layers of carbon atoms that have covalent bonds are
attached to each other by a Van der Waals bond which is a weak bond that is easily
broken. One side of a “neutral” molecule is slightly positive and the other side slightly
negative where this bond has asymmetrical chargea and distribution. Thus, of the weak
bonding this is why graphite is the softest mineral.
30. What holds rocks together?
In igneous and metamorphic rocks contain interlocked minerals.
The forces that hold the grains of sedimentary rocks are less obvious. Sedimentary rocks
form by compaction, during which the mineral grains in the sediment are squeezed and
compressed by the weight of overlying sediment. Water might deposit new minerals such as
calcite and quartz or iron oxide into open spaces that act as a cement.
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