GEOCHEMISTRY Flashcards
1
Q
- Who first coined Geochemistry, where and when?
A
Christian Friedrich schonbein, 1838, Univ of Basel, SZ
2
Q
- Who is the Father of Geochemistry considered as the first Geochemist?
A
Frank Clarke
3
Q
- What was his book and when was it published?
A
Data of Geochemistry, 1908
4
Q
- This refers to the average concentration of Elements in the crust
A
Clarke of Concentration
5
Q
- Who is the father of modern geochemistry and crystal chemistry who correlated the mineral formation and structure to its chemical composition?
A
Victor Goldschmidt
6
Q
Classification of Minerals according to preferred Hosts
A
Lithophiles = Rock and Oxygen Loving
Chalcophiles = Ore Loving Sulfur Loving
Siderophiles = Iron Loving
Atmophile = Gas Loving
7
Q
- Study of the Chemistry of the universe
A
Cosmochemistry
8
Q
- Theoretical Age of the UNiverse
A
13.7 Ga
9
Q
- Who proposed big bang theory?
A
Belgian Priest, George Lemaitre
10
Q
Model of the evolution of the universe that postulates its origin from a hot dense mass that expanded rapidly and cooled
A
Big Bang
11
Q
- When was big bang proposed?
A
1920s (1927)
12
Q
- Evidences or Supporting observation of Big Bang?
A
1) REd Shift or the Expansion of the Universe
2) Abundance of light elements such H, He, Li, and
3) Pervasive Background Radiation or Cosmic Microwave Background (CMB) radiation
13
Q
- Who proposed Red Shift and when?
A
Edwin Hubble in 1929
14
Q
- Who obseved the Cosmic Microwave Radiation?
A
Arno Penzias and Robert Wilson in 1965
15
Q
- Where was CMD first observed?
A
Bell Telephone Laboratories
16
Q
- What 2 methods were used by scientists to date the universe?
A
1) Oldest Stars, and
2) Extrapolation though the rate of expansion of galaxies
17
Q
A segment of universe formation wherein the universe became neutral and Opaque
A
Dark Age
18
Q
End of Dark Age
A
Cosmic Ionization
19
Q
Nuclear Process which forms stars
A
Nuclear Fusion
20
Q
- This is the process of creation of elements
A
Nucleosynthesis
21
Q
- This refers to the creation of H, He, and Li during the first few moments of big bang and became the starting ingridients for all other elements?
A
Cosmological Nucleosynthesis
22
Q
- This refer to the creation of elements with atomic masses up to 26Fe through variety of nuclear reactions
A
Stellar Nucleosynthesis
23
Q
- How are elements with atomic masses greater than 26 created?
A
Through explosive burning during supernova
24
Q
- Sequence of burning during nucleosynthesis
A
H - He - C - O - Si- Fe
25
21. What is the constant H:He ratio which is largely dictated by Big Bang?
12.5
26
22. Why is Li, B, Be anomalously low in concentration?
Because they are unstable and are tend to be used and destroyed in the production of C12
27
23. What is Oddo Harkins Rule?
sawtooth pattern of elemental abundance in the universe in whic elements with even atomic numbers are more abundant than those with odd atomic numbers
28
24. This element has the highest binding energy per nucleon and is the most stable
Fe
29
25. This is the diagram used to classify stars
Hertzsprung-Russel Diagram
30
26. Which are the hottest stars?
White Dwarfs
31
27. Who proposed Nebular Hypothesis (2)?
Immanuel Kant and Pierre Simon de Laplace
32
28. How did scientist discover the age of the solar system?
Determining the age of the oldest rock
33
29. What is the oldest rock in the earth?
Rock 14321 found in Moon
34
30. Who and when was the rock discovered?
Alan Shepard, Apollo 11 Astronaut in Feb 6, 1971
35
31. How old is the rock and what dating technique was used?
4.011 Ga, Zircon Dating
36
32. What is the oldest Material on earth
Pre-Solar Grains of Murchison Meteorite which fell in Australia in 1969
37
33. Age of the oldest materials and what dating technique used?
7.5 Ga Neon21 Isotope
38
Oldest material formed on Earth and its age?
Jack Hills Zircon in a Quartzite/Metaconglomerate 4.4Ga
39
Where was this oldest material found?
Western Australia
40
34. What similar compositions do terrestrial plaents have?
high temp minerals, Fe-Mg Silicates Metallic Alloy
41
35. What similar compositions do Jovian Plaents have?
Low temp minerals, Methan, Ammonia and Water
42
36. This is the arrangement of condensation of minerals depending on the temperature and distance from the sun
Condensation Sequence
43
37. The line which marks that the temperature is cold enough for volatile compounds to condense into solid grains
Frost line
44
38. Relative abundance of Materials in the Solar Nebular
98% Light gases
1.4% H cmpds
0.4% Rocks and
0.2% Metals
45
39 Solar system composition by mass
Sun 99.85%,
0.10% Jupiter
0.04% other planets,
0.01% Comets
0% satellites, rings and asteroids, Meteroids and
dut 0.0000001%
46
40. Meteorite whch comes from differentiated planetisimals with Taenite as primary composition?
Magmatic Fe Meteories
47
41. Composed of Pallasites and Mesosiderites?
Stony Fe
48
42. Composed mostly of basaltic rocks from crusts and mantle of planetisimals
Achrondrite
49
43. Most abundant meteorite
Ordinary Chondrites
50
44. Meteorites composed of Magnesium Pyroxene
Enstatite Chondrites
51
45. These are the most primitive Chondrites
Carbonaceous Chrondrites
52
46. What does Carbonaceous Chronites represent?
Bulk Composition of the Sun
53
47. Difference between chemical and physical classifications of earth's layers?
The former depends mainly on composition while the latter depends on the rheology
54
48. Differentiate Oceanic and Continetal Crust based on Composition?
Oceanic is Basaltic (SiMg) in COmposition while Continental is Granitic to Granodioritc (SiAl)
55
49. Differentiate Oceanic and Continental Crust based on Ave. Thickness?
Oceaning is 6.5-7 km while Continental is 35km
56
50. Thickness range for Oceanic Crust
3-15 km
57
51. Thickness range for Continental crust
20-60km
58
52. DEnsities of Oceanic and Continental Crust respectively?
3.3g/cc and 2.7g/cc
59
53. Differentiate Lithosphere and Asthenosphere based on Rheology and COmposition?
Lithosphere is brittle and is composed of the whole Crust and the Upper Mantle while Asthenosphere is ductile and is composed of the Upper Mantle
60
54. The discontinuity between Curst and Mantle?
Mohorivicic
61
55. The discontinuity between Mantle and COre?
Gutenberg
62
56. The discontinuity between outer and inner core?
Lehmann
63
57. Bulk density of earth?
5.52 g/cc
64
58. Why do earthquakes have a maximum depth of 100km?
BEcause the lithosphere's rigid environment generates earthquakes and it exists only up to 100 lkm
65
59. What generates the magnetic field of the earth?
Convection of the liduid outer core and the rotation of the earth
66
60. Beta polymorph of Olivine?
Wadsleyite
67
61. Gamma polymorph of Olivine?
Ringwoodite
68
62. Why is there a discontinuity at 400km in the mantle?
Because Olivine has undergone phase transformation
69
63. Composition of the Lower Mantle?
Brdigmanite or Mg Pervoskite
70
64. Who and when was periodic table discovered?
Dmitri Mendeleev 1864
71
65. Nuclides of the same chemical ellement having diff atomic masses?
Isotopes
72
66. What is the name of the Group IA of the periodic table?
Alkali metals
73
67. What is the name of Group IIA?
Alkali Earth Metals
74
68. What is the name of Group IIIB to IIB?
Transition Metals
75
69. What is Group IIIA to VIIA
Non-Metals
76
70. What is Group VIIA?
Halogens
77
71. What is Group VIIIA?
Noble Gases
78
72. Bonds wherein electrons are shared?
Covalent
79
73. Bonds wherein Electrons are transferred?
Ionic
80
74. Elements which accepts Electrons and is negatively charge?
Anions which are mostly non Metal
81
75. Elements which donates electrons and is positively charged?
Cations which are mostly metal
82
76. Bonds in which positively charged nucleus are surrounded by a sea of electrons that are freely moving?
Metallic bond
83
77. Minerals with same chemical composition but have diff crystal structure?
Polymorph
84
78. Minerals with the same crystal structure but have diff chemical formula?
Isomorph
85
79. What is the difference between Calcite and Aragonite?
Calcite is Hexagonal, Araonite is Orthorhombic
86
80. What is the difference between Pyrite and Marcasite?
Pyrite is Isometric while Marcasite is Orthorhombic
87
81. This silica polymorph is used as an indicator of an ultra-high pressure environment or rocks
Coesite
88
82. This silca polymorph are usually found in impact craters and display birefringence uner the microscope?
Shock Quartz
89
83. Difference between Kyanite, Sillimanite and Andalusite?
Sillimanite and Andalusite are Orthorhomnbic and goes extinct under the microscope while Kyanite is Triclinic
90
84. Difference between Diamond and Graphite?
Diamond is Isometric while Graphite is HExagonal
91
85. Differentiate Sanidine, Orthoclase, and Microcline?
They are all k-felds but Sanidine and Orthoclase are Monoclinic while Microcline is triclinic. Sanidin forms in the highest T among the three while Microcline is the lowest. They are polymorphs based on order-disorder
92
86. Which of the Goldschmidt Classification of Elements are mostly found in the Core?
Siderophiles because these element have high density and sink into the core and readily dissolves in Iron
93
87. Which of the Goldschmidt Classification of Elements are mostly found in the Crust?
Lithophiles because these elements readily combine with oxygen
