Pericyclic Analogies
Transition State Structures
Proton Affinities
Electrocyclic and Sigmatropic Rearrangements
http://blueline.ucdavis.edu/2ndTier/3rdTier/PeriAnalogies.html
https://en.wikipedia.org/wiki/Sigmatropic_reaction
https://en.wikipedia.org/wiki/Pericyclic_reaction
https://en.wikipedia.org/wiki/2,3-sigmatropic_rearrangement
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Molecular Hydrogen
Hydrogen Atom Shift
Hydride Shifts
Proton Affinities
Transition Metals
Transition State
Structures Rearrangements
Electrocyclic
Sigmatropic
Pericyclic
Reaction Ring
Double Bonds
Heterocyclic
Heterolytic
Homolytic
Cleavage
Hydrogen Atom Transfer
(HAT) Pathways
Methyl Donors (𝐶𝐻3)
Methylation
Cycloaddition
Photoredox Catalysis
Vitamin D3
Cholecalciferol
Dehydrocholesterol
Carbon 19 9
UVB
Heat Light
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Molecular Hydrogen
H2 Gas
Magnesium
Hydrochloric Acid
HCL Betaine
Molecular hydrogen: a preventive and therapeutic medical gas for various diseases
https://pmc.ncbi.nlm.nih.gov/articles/PMC5731988/
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Single-Displacement Reaction
List of common metals that displace hydrogen from acids (arranged in order of reactivity)
Reactive Metals:
Lithium (Li) - Highly reactive
Potassium (K)
Barium (Ba)
Calcium (Ca)
Sodium (Na)
Magnesium (Mg)
Aluminum (Al)
Manganese (Mn)
Zinc (Zn) - Commonly used in lab
Chromium (Cr)
Iron (Fe)
Cadmium (Cd)
Cobalt (Co)
Nickel (Ni)
Tin (Sn)
Lead (Pb) - Slow reaction
Metals such as Copper, Mercury, Silver, Platinum, and Gold are below hydrogen in the activity series and cannot displace hydrogen from dilute acids.
Magnesium hydride is not typically used as an electrode material in standard water electrolysis for purification. Instead, it is used in a hydrolysis reaction with water to produce hydrogen gas and magnesium hydroxide, which can be part of a water treatment system. The resultant magnesium hydroxide can then be used in water purification to treat acidic wastewater and remove heavy metals.
Role in Water Purification
The primary use of magnesium compounds in water treatment is related to the resulting magnesium hydroxide byproduct of the hydrolysis reaction:
pH Adjustment: Magnesium hydroxide is a weak alkali used to neutralize acidic wastewater.
Contaminant Removal: It helps precipitate heavy metals (e.g., copper, lead, cadmium) as insoluble hydroxides, which can then be removed.
Flocculation: The particles help clump together suspended solids, making them easier to filter out.
Electrolysis Context
In a conventional water electrolysis system, electrodes are used to split water molecules.
Cathode: Hydrogen gas is produced at the cathode (negatively charged electrode).
Anode: Oxygen gas is produced at the anode (positively charged electrode).
If metallic magnesium or magnesium-based materials are used as anodes in an aqueous electrolyte, they suffer from surface passivation due to the formation of an
layer, which is highly insoluble and impedes the electrochemical reaction.