Putting All Minerals in Perspective
Chemical Properties of Minerals I
PC NH O S
Carbohydratesand Fats
ProteinsNucleicAcids
Creating the molecules of life
So, why do we need more?
But…will these six elements give us life?
give us movement?
allow us to grow and develop?
generate energy?
maintain internal homeostasis?
build bones and teeth?
maintain fluid balance?
Will they….
stimulate muscles to contract?
propagate nerve impulses?
determine the color of fur and skin?
optimize our immune system?
What chemical elements do we associate with life?
Na K Ca Mg Cl
PC NH O S
Fe Zn Cu Mn Se
V Si As Mo I
Co
Ni Cr
Br F
Sn B ? 28?
Chemical Principles Underlying the Properties
of Minerals
First transition series
Macrominerals
Microminerals
3d
4d
5d
Noble Gases
Iodine(heaviest)
Non-metals
Properties of Minerals Relevant toFunction and Selection
5 major properties related to a particular mineral’sfunction and selection
1. Charge or valance state of the ion
2. Solubility in water
3. Redox property
4. Coordination geometry
5. Choice of ligand
Valance State of Macro- and Microminerals
Macro Micro
Sodium Na+ Iron Fe2+, Fe3+,Fe4+ Potassium K+ Zinc Zn2+
Magnesium Mg2+ Copper Cu+, Cu2+,Cu3+
Calcium Ca2+ Manganese Mn2+,Mn4+,Mn5+
Chlorine Cl- Cobalt Co+, Co2+, Co3+
Nickel Ni+, Ni2+
Molybdenum Mo4+, Mo5+,Mo6+
Iodine I-
Denotes most common oxidation states in solution at neutral pH
Solubility in Water
Rule: A mineral that is freely soluble in water can easily move through extracellular and intracellular fluids.
Rule: Paradoxically, charge on the molecule is not the only determinant of water solubility, atomic number must also be considered
Rule: Minerals capable of “hydrolyzing” water work against solubility
Solubility varies with charge and atomic number
Na+, K+ 10-1 M
Ion/complex
Mg2+, Ca2+ 10-3 M
Zn2+ 10-9 M
Cu2+
Fe3+
10-12M
10-17M
Macrominerals
Microminerals
pH 7.0 with chloride as counter ion
Metals as hydrolytic agents
Fe3+ + 3H2O Fe(OH)3 + 3H+
Insoluble hydroxide
Cu2+ + 2H2O Cu(OH)2 + 2H+
H+
Acid (low pH) favors solubility
Oxidation-Reduction (redox metals)
Rule: Metals with multiple valance states have the capacity to take and give electrons, thereby acting as oxidizing and reducing agents, respectively.
Corollary: Fixed valence metals cannot behave as redox agents
Cu2+ + Fe2+ Cu+ + Fe3+
Copper is reduced, iron is oxidized
Copper is oxidized, iron is reduced
Zn2+ + Fe2+ No reaction
Coordination Complexes
Rule: Metal ions, especially micro- adhere to a strict configuration in number of ligands and spatial orientation when forming complexes
Rule: Adherence to coordination requirements has a major impact on selection of a particular metal ion for a function and rejection of others to replace the selected one.
Rule: Metal ion antagonism and synergism is strongest when two metals have the same coordination properties
3d10
3d9
Cu+ (tetrahedral) d10 dsp3 4
Zn2+ (tetrahedral) d10 dsp3 4
Cd2+ (tetrahedral) d10 dsp3 4
Hg2+ (linear) d10 dsp 2
Cu2+ (sq. plan) d9 dsp2 4
Ag2+ (sq. plan) d9 dsp2 4
Fe2+ (octahedral) d5 d2sp2 6
Ion Orbital Config Coordination No.
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