Presentation on theme: "Atoms are the smallest components of nature"— Presentation transcript:
1 Atoms are the smallest components of nature with the properties of a given substance.Electrons (negative charge)Protons(positive charge)Neutrons(no charge)Suggested tips to give students:Protons are “positive”. Neutrons are “neutral”.
2 For any given element:Atomic Number is the number of protons in the nucleus. Mass Number is the number of neutrons and protons in nucleus.Suggested tips to give students:What is the Atomic Number of carbon? (6) What is the Mass Number of carbon? (12)
3 Variations in mass number create Isotopes Suggested tips to give students:Iso (equal) tope (place) = same place in Periodic Table of The Elements.Variations in mass number create Isotopes
4 Atoms bond to achieve a stable electron configuration Atoms bond to achieve a stable electron configuration. Most atoms bond to achieve 8 electrons in the outer shell - the so-called“Octet Rule”
5 Variations in electrical charge form Ions negative charge = Anion positive charge = Cation
6 Minerals are compounds of atoms bonded together … “to achieve a stable electron configuration” …IONIC BONDINGSuggested tips to give students:“Opposites attract”
7 COVALENT BONDING METALLIC BONDING … “to achieve a stable electron configuration” …Suggested tips to give students:“sharing”METALLIC BONDINGBonding between atoms within metals. All “free” electrons shared in an “electron sea”.
8 Igneous Minerals crystallize from cooling magma. Sedimentary Minerals crystallize from dissolved elements in water, or as a product of biological metabolism.Suggested tips to give students:Whole chapters devoted to each type coming up!Metamorphic Minerals recrystallize from existing minerals where conditions in the crust cause high heat and pressure.
9 Magma from three major tectonic settings Suggested tips to give students:Where Igneous Minerals are formed - source rock.
10 Oxygen and Silicon are the two most abundant elements in the crust. Suggested tips to give students:Oxygen and silicon content is high in minerals that crystallize from melted crustal rock. Minerals that come from the mantle are high in iron.
11 Silica - 4 oxygen atoms surround a single silicon atom, forming (SiO4)4- Each oxygen atom covalently shares 1 electron with the silicon atom, jointly filling its outermost shell.O2-2e8P6eSuggested tips to give students:Atoms in a liquid, either magma or water, arrange in an orderly fashion (due to electrical charges), progressively building crystals. Silica tetrahedron on left. Halite example on right.Si4+8e2e4e14P
13 Types of Silicate Structures Na+Ca 2+Al 3+Fe 2+ (3+)Mg 2+K +Suggested tips to give students:Whatever the ultimate crystal structure, by the time a mineral has completed crystallization, it is electrically neutral. Silicate structures are not neutral – still require cations.Metallic Cations
14 Metallic Cations Join Silicate Structures to Form Neutral Compounds. Cations of like size and charge substitute within silicate structures.This forms a wide variety of minerals.Most substituted Cation pairs are Na+/Ca2+,Al3+ /Si4+, and Fe2+/Mg2+.Olivine forms by Single Cation Substitution.Plagioclase Feldspar forms by Double Cation Substitution.(Mg2+, Fe2+)2Si4+O2-4
16 Olivine: single tetrahedron (SiO4)4- [Fe22+(Si4+O42-)4-] or [Mg22+(Si4+O42-)4-]–8 = 0 or –8=0Fayalite (Fe2SiO4)Forsterite (Mg2SiO4)Feldspar: 3-D framework (Si3O8)4-[Na1+Al3+Si34+O82-]or [Ca2+Al23+Si24+O82-]–16=0 or –16=0Albite NaAlSi3O8Anorthite CaAl2Si2O8
17 There are seven common rock-forming minerals. AmphiboleOlivinePyroxeneQuartzSuggested tips to give students:Group names are given to minerals with compositional variation within a particular range. Each mineral within a group has a specific composition. Common irregularities in crystallization or chemical impurities produce the variations.The Feldspar GroupOrthoclase and PlagioclaseBiotiteCalcite
18 As the Si and O build crystalline structures and the metallic cations play single and double substitution, the entire magma chamber grows into a solid mass of minerals….