Final Exam / Lecture Exam 1

Question 1

1. A mineral:
   a. can be naturally occurring or man-made
   b. has a well defined composition or limited range of compositions
   c. has an ordered arrangement of atoms
   d. both b and c
   e. all of the above

Answer 1

D

Question 2

2. Ionic bonds:
   a. form when a proton is transferred from one atom to another
   b. form when an electron is transferred from one atom to another
   c. result from the electrical attraction between positively and negatively charged ions
   d. result from sharing of electrons between atoms
   e. both b and c are correct

Answer 2

E

Question 3

3. The chemical bonds found in silicates:
   a. are predominantly ionic in character
   b. are predominantly covalent in character
   c. have both ionic and covalent bond characteristics
   d. are predominantly probiotic in character

Answer 3

C

Question 4

4. Elements on the left side of the periodic table:
   a. have nearly empty outer election shells, so readily give up elections to become cations
   b. have nearly empty outer electron shelts, so readily give up elections to become anions
   c. have nearly full outer electron shells, so readily gain elactrons to become anions
   d. have nearly full outer electron shells, so readily gain electrons to become cations
   e. have completely filled outer eledtron shells so cannot gain or lose elections so are unreactive

Answer 4

A

Question 5

5. The 4th and 5th rows of the periodic table contain more elements than the 1st three rows because:
   a. the elements in the 4 and 5th rows have larger s - orbitals that hold more electrons
   b. the elements in the 4 and 5th rows have more p - orbitals so can hold more electrons
   c. the elements in the 4 and 5th rows are filling d - orbitals in addition to s - and p-
   Orbitals
   d. the elements in the 1st three rows only have larger d - orbitals that hold more electrons

Answer 5

C

Question 6

6. The Periodic Table is laid out in accordance with the number of electrons in the outer shell of the atom of each element. How many electrons occupy the outer shell of the group (column) 1 element?
   a. 1
   b. 7
   c. 8
   d. 18

Answer 6

A

Question 7

7. What is the usual valence state of an ionized group 1 atom?
   a. -1
   b. +1
   c. -7
   d. +8

Answer 7

B

Question 8

8. How many electrons occupy the outer shell of the group (column) 17 elements (second from the right) in periods (rows) 2 and 3?
   a. 1
   b. 7
   c. 8
   d. 18

Answer 8

B

Question 9

9. What is the usual valence state (electrical charge) of an ionized group 17 atom?
   a. -1
   b. +1
   C. -7
   d. +8

Answer 9

A

Question 10

10. Most of the iron in the Earth was originally produced:
    a. during the Big Bang
    b. during the first few seconds of a super nova explosion
    c. inside of Sun-like stars in the proton-proton reaction
    d. inside of stars more massive than the Sun in the alpha process

Answer 10

D

Question 11

11. The most common element in the Earth’s crust is:
    a. silicon
    b. oxygen
    c. iron
    d. carbon

Answer 11

B

Question 12

12. According to Goldschmidt’s classification, chalcophile elements will concentrate:
    a. in an iron-rich liquid
    b. in a sulfur-rich liquid
    c. in a silica-rich liquid
    d. as a gas

Answer 12

B

Question 13

13. Which of the following terms describes well-formed crystals?
    a. euhedral
    b. subhedral
    c. anhedral
    d. amorphous

Answer 13

A

Question 14

14. Graphite and diamond are ________ of carbon.
    a. pseudomorphs
    b. isomers
    c. polymorphs
    d. isotopes

Answer 14

C

Question 15

15. The rapid bonding of atoms at corners of growing crystals often results in the formation of:
    a. cleavage planes
    b. dendrites
    c. twins
    d. glass

Answer 15

B

Question 16

16. Most crystal nuclei formed during the initial stages of crystal growth:
    a. tend to grow larger because their high surface/volume ratio allows them to attract more ions
    b. tend not to grow larger because their high surface/volume ratio causes them to redissolve
    c. cannot grow larger once they reach a critical size
    d. are negatively charged and so grow by attracting larger anions

Answer 16

B

Question 17

17. Pericline, Baveno, Carlsbad, cyclic, penetration and polysynthetic are all words to describe:
    a. pseudomorphism
    b. polymorphism
    c. twinning
    d. feldspars

Answer 17

C

Question 18

18. Which type of point defect is characterized by the mislocation of an ion from its normal site to an interstitial site?
    a. Schottky
    b. Frenkel
    c. Impurity
    d. Edge dislocation

Answer 18

B

Question 19

19. Penetration twins:
    a. occur when two of the same mineral grow through each other
    b. represent one mineral with two domains that share a volume of atoms
    c. represent one mineral with two domains that share a common plane
    d. occur when two polymorphs grow together

Answer 19

B

Question 20

20. The modern classification system of minerals is based on:
    a. color
    b. type locality
    c. chemical composition
    d. luster

Answer 20

C

Question 21

21. Minerals will not crystallize from magmas that are above their melting points because:
    a. the atoms are moving too fast to form bonds
    b. the atoms are not ionized so cannot form ionic bonds
    c. the atoms are too widely separated from each other
    d. the atoms are in the wrong valence state to form ionic bonds

Answer 21

A

Question 22

22. Which of the following pairs of mineral compositions belong in the same mineral group?
    a. FeCO3 and FezSi04
    b. FeCOs and CaCO,
    c. CaCOs and CaSO4

Answer 22

B

Question 23

23. Which of the following silicate groups consists of silica tetrahedra in which all of the apical oxygens are shared with other tetrahedra?
    a. phyllosilicates (sheet silicates).
    b. tectosilicates (framework silicates)
    c. sorosilicates (paired tetrahedral silicates)
    d. orthosilicates (Island silicates)

Answer 23

B

Question 24

24. Olivine (Mg, Fe)2 SiO4 contains variable proportions of Mg and Fe. This is an example of
    a. a polymorph
    b. solid solution
    c. coupled substitution
    d. an impurity defect

Answer 24

B

Question 25

25. Plagioclase varies in composition from CaAl, Si, ° to NaAISi, O this is an example example of
    a. a polymorph
    b. coupled substitution
    c. an impurity defect
    d. A Frenkel defect

Answer 25

B

Question 26

26. Which mineral class comprises the greatest percentage of the Earth’s crust?
    a. silicates.
    b. oxides.
    c. sulfides.
    d. carbonates.

Answer 26

A

Question 27

28. A 2-fold axis of symmetry:
    a. Is equivalent to a mirror plane of symmetry in two dimensions
    b. represents a rotation of 180°
    c. is equivalent to an inversion center of symmetry in three dimensions
    d. all of the above

Answer 27

B

Question 28

29. The term “form” in crystallography refers to:
    a. a crystal’s morphology or shape
    b. a set of identically shaped crystal faces related by symmetry
    c. a group of crystal faces whose intersections are all parallel
    d. the impression one crystal makes on another during growth

Answer 28

B

Question 29

30. The symbol 2/m refers to:
    a. 2 inversion centers
    b. two mirror planes perpendicular to each other
    c. two 2-fold axes perpendicular to each other
    d. a 2-fold axis perpendicular to a single mirror plane

Answer 29

D

Question 30

31. A 4 (“bar 4”) rotoinversion axis:
    a. is equivalent to a 4-fold rotation axis with a perpendicular mirror plane
    b. is equivalent to a 4-fold rotation axis and an inversion center applied separately
    c. is equivalent to two 2-fold rotation axes perpendicular to each other
    d. is unique, having no equivalence with combinations of other symmetry operators

Answer 30

B

Question 31

32. Special angles in reference to rotation axes arranged in a circle:
    a. divide evenly into 360°
    b. are divisible by n
    c. are angles related to irrational numbers
    d. are not allowed by rotation axes

Answer 31

A

Question 32

33. What symmetry operator results from having two 2-fold rotation axes that are perpendicular to each other?
    a. a 4-fold rotation axis
    b. two 4-fold rotation axes
    c. a third 2-fold rotation axis
    d. a 3-fold rotation axis

Answer 32

C

Question 33

34. The notation 322 is:
    a. a point group consisting of one 3-fold rotation axis and two 2-fold rotation axes
    b. a point group consisting of one 3-fold rotation axis and three 2-fold rotation axes
    c. a 3-fold rotoinversion axis
    d. a 3- fold rotation axis with a perpendicular mirror plane

Answer 33

B

Question 34

35. How are point groups are related to crystal systems:
    a. each of the six point groups designates a different crystal system
    b. each of the 32 point groups belongs to one of six crystal systems
    c. each of the 32 crystal systems belongs to one of six point groups
    d. point groups are another term for space groups

Answer 34

B

Question 35

27. Which three-dimensional flat-sided shape has the greatest symmetry?
    a. sphere
    b. cube
    c. rhombohedron
    d. hexagonal trapezohedron

Answer 35

B