Group 2B Elements and Zinc Properties

Group 2B: The Volatile Metals

• Includes zinc (Zn), cadmium (Cd), mercury (Hg), and copernicium (Cn)
• Also called zinc group
• Found in Earth's crust in varying proportions
• Group 2B is a transition metal
• Transition metals are defined by having an incomplete d subshell in their atoms or cations. This definition excludes zinc, cadmium, mercury, and likely Uub (ununbium).

Zinc (Zn)

• Silvery white metal with a bluish tint
• Found in zinc blende (zinc sulfide) and calamine (zinc silicate) ores
• Essential trace element, component of hundreds of enzymes
• Participates in insulin synthesis, storage, and release
• Protective coating in galvanized iron
• Used in batteries and dry cells

Galvanizing

• Process of coating iron with zinc to prevent rust
• Zinc is a stronger reducing agent than iron, so it oxidizes preferentially, protecting the iron.

Zinc (Zn) Pharmacological Actions

• Astringent
• Antiseptic
• Deodorant
• Antiperspirant

Calamine

• Also known as prepared calamine, lapis calaminaria, and artificial calamine
• Used to relieve itching, pain, and discomfort from minor skin irritations (e.g., poison ivy, poison oak, poison sumac)
• Also used to dry oozing and weeping
• Available without prescription

Zinc Acetate Zn(CH₃CO₂)₂

• Precipitating germicide
• Also known as a biocidal agent, antiseptic, or disinfectant
• Used to inactivate microorganisms on surfaces or instruments

Zinc Carbonate (ZnCO₃)

• Mechanical protectant, odorless, white, and sand-like solid
• Used in cosmetics, lotions, porcelains, pottery, rubber, as a feed additive, and as medication
• A promising cosmetic ingredient due to its fungicidal and antiseptic properties
• Used in bath products, makeup, personal hygiene products, shaving products, and oral care products

Zinc Chloride (ZnCl₂)

• Also called butter of zinc
• Component of Lucas Reagent, used to identify aliphatic alcohols
• Can be used to test for alcohols using the cross and Bevan's Reagent (a mixture of HCl and ZnCl₂).

Zinc Oxide (ZnO)

• Also known as flower of zinc, zinc white
• Topical protective agent, mild astringent, and antiseptic
• Used in calamine lotion and as a physical sunblock (e.g., Banana Boat sunscreen)
• White pigment used in watercolors and to impart opacity to other colors

Zinc Sulfate (ZnSO₄)

• White vitriol, a precipitating germicide
• Astringent, emetic, and weak antiseptic
• Used to treat zinc deficiency
• Adjunct to oral rehydration therapy in children (under 5 years) with acute and persistent diarrhea

Zinc Undecylenate

• Mild antiseptic and astringent
• Antimicrobial agent used to treat fungal infections like athlete's foot, dermatophilosis, and candidiasis
• Used topically in dosage forms and as a disinfectant in cosmetics

Zinc Pyrithione

• Anti-seborrheic, anti-dandruff agent (e.g., head and shoulders shampoo)
• Antibacterial, antimicrobial, and antifungal properties
• Used in treating seborrheic dermatitis (dandruff), scalp psoriasis, and acne

Zinc Toxicity: Metal Fume Fever

• Toxicity associated with zinc
• Caused by inhalation of zinc oxide (ZnO) fumes
• Symptoms include flu-like symptoms (fever, shaking chills, fatigue, etc)

Cadmium (Cd)

• Most cadmium usage in the United States is associated with zinc, lead, and copper production
• Relatively unreactive metal
• Used in plastics, batteries, coatings, and pigments
• Intermediate in properties to zinc (Zn) and mercury (Hg)
• Water-soluble compounds have astringent properties
• Used in rechargeable batteries
• Acts as an antagonist to copper (Cu) and iron (Fe) in the body

Cadmium Sulfate (CdSO₄)

• Topical astringent for eye infections
• White, crystalline, odorless solid
• Used as a reagent in vacuum tubes, fluorescent screens, electroplating baths, and as a fungicide

Cadmium Sulfide (CdS)

• Bright yellow pigment,
• Used as an anti-seborrheic in seborrheic dermatitis, but can induce photosensitization (e.g., Capsebon®)
• Used in plastics, solar cells, PDs, light-emitting diodes, and lasers

Cadmium Poisoning: Itai-Itai Disease

• First recognized in Japan in the 1960s
• Result of chronic cadmium poisoning from human activities related to industrialization
• Characterized by osteomalacia (bone softening) with severe bone pain
• Associated with renal tubular dysfunction

Mercury (Hg)

• Latin: Hydrargyrum
• Liquid metal at room temperature
• Easily forms amalgams with other metals (e.g., gold, silver, tin)
• Historically used in dental fillings
• Cinnabar (HgS) is the most common source of ore for refining elemental mercury; a brilliant red or scarlet pigment called vermilion
• Used to recover gold from its ores

Ammoniated Mercury

• Other name: Mercury amidochloride
• White precipitate
• Antiseptic

Nitromersol (C₂H₃HgNO₃)

• Antiseptic and disinfectant

Mercuric Chloride (HgCl₂)

• Corrosive sublimate
• Used as a disinfectant for utensils and surgical instruments (1:1000 dilution) before the use of certain procedures, including treatment of syphilis

Mercurous Chloride (Hg₂Cl₂)

• Also known as Calomel
• An antiseptic used by slow liberation of mercuric ion
• Historically a cathartic of choice

Yellow Mercuric Oxide (HgO)

• Yellow precipitate
• Used in merbromin (Mercurochrome®), thimerosal (Merthiolate®), and benzalkonium chloride (new Merthiolate®)

Organic Mercury Poisoning: Minamata Disease

• Neurological disease caused by methyl mercury poisoning
• Symptoms include ataxia, numbness, general muscle weakness, and damage to hearing and speech
• In severe cases: insanity, paralysis, coma, and death

Chronic Mercury Poisoning: Mad Hatter's Disease

• Also known as Erethism
• Caused by mercury exposure through the inhalation of mercury vapors
• Characterized by emotional, mental, and behavioral changes

Mercury Poisoning in Children: Acrodynia/Pink Disease

• Greek term meaning "painful extremities"
• Manifestation of chronic mercury poisoning
• Dermatological and systemic manifestations of exposure to various mercury forms in children

Antidote for Mercury Poisoning

• 1st line: Sodium formaldehyde sulfoxylate
• 2nd line: Dimercaprol and penicillamine (Cuprimine®)
• 3rd line: DMSA (dimercaptosuccinic acid) and succimer

Other Volatile Metal Toxins and Antidotes

• Elemental Hg: DMSA, penicillamine
• Inorganic Hg salts: Oral DMSA, BAL
• Organic Hg: DMSA (not BAL)
• Emergency ingestion (HgCl₂): Administer 1 egg white for every 250 mg of ingested HgCl₂

Group 2A: The Alkaline Earth Metals

• Includes beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), and radium (Ra)
• Magnesium is the second most abundant metallic element in the sea.

Magnesium (Mg)

• 6th most abundant element in Earth's crust
• Obtained via molten chloride electrolysis (Dow process)
• 2nd major intracellular cation
• Protects against corrosion as sacrificial anode
• Natural Ca2+ channel blocker

Magnesium Functions

• Needed for DNA repair
• Moderates cellular differentiation, proliferation, and tissue sensitivity to insulin
• Component of enzymes involved in ATP synthesis, energy release, muscle contraction, and protein synthesis
• Deficiency (hypomagnesemia) is associated with increased neuromuscular irritability

Magnesium Oxide (MgO)

• Mechanical protectant from air, odorless, white, and sand-like solid
• Used in cosmetics, lotions, porcelain, and pottery.

Magnesium Oxide Uses

• Antacid
• Mg deficiency treatment
• Universal antidote
• Zinc phosphate cellulose ingredient

Magnesium(OH)₂ Uses

• Laxative
• Antacid

Magnesium Tri-silicate Hydrated (Mg₂SiO₄•2H₂O)

• Suspending agent in chocolate
• Thickening agent in chocolate
• Laxative

Magnesium Sulfate (MgSO₄)

• Treatment for eclampsia
• Used parenterally to treat hypomagnesemia and torsade de pointes.

Magnesium Carbonate (MgCO₃)

• Antacid
• Laxative
• Toothpaste additive 

Magnesium Phosphate (Mg₃(PO₄)₂)

• Antacid
• Potential laxative
• Phosphate binder

Magnesium Salicylate

Anti-inflammatory agent

Magnesium Sulfate (MgSO₄)  

• Used in pre-eclamptic/eclampsia treatment,

Magnesium Trisilicate

• Non-systemic antacid 

Talc

• Mineral,
• Natural hydrated aluminum silicate,
• Inert absorbent, demulcent, dusting powder

Magnesium Perchlorate

• Drying agent (eliminates water from organic solutions)

Calcium (Ca)

• Major component of bone marrow
• Component of hydroxyapatite
• Important for blood clotting, enzyme activation, and acid-base balance
• Also essential in lactation, nerve function, muscle function, including heart muscle, and membrane permeability

Calcium Toxicity (Hypercalcemia):

• Constipation, renal stones, cardiac arrhythmias, cardiac arrest, and depressed brain function (e.g., lethargy or coma)
• Often associated with hyperparathyroidism or metastatic cancer.

Other Calcium Products and Uses

• Calcium Carbonate: Antacid, osteoporosis prevention, used in preparing bandages, cast impressions
• Calcium Hydroxide: Antacid, laxative
• Calcium Sulfate: Aid in tableting, casts, supporting treatment, nutritional supplements, preparing bandages and cast impressions
• Calcium Phosphate: Antacid, phosphate binder in kidney failure.

Strontium

• Similar properties to calcium.
• Produces a crimson colored flame test 

Strontium Products and Uses

• Tooth desensitizing agent in toothpastes
• Strontium chloride (Sr 89 injection): used to diagnose osteogenesis imperfecta (brittle bone disease)
• Strontium bromide: sedative effects, bipolar disorder treatment
• Strontium lactate: osteoporosis treatment

Barium

• Used in X-ray imaging to visualize the digestive tract
• Radiopaque, does not dissolve in water used in contrast in X-rays and CT scans
• Used to help identify ulcers, tumors, and blockages

Radium

• Still used in targeted alpha-particle therapy to treat bone metastases in prostate cancer.
• Delivering localized radiation to destroy cancerous cells

Group 1B: The Coinage Metals

• Copper (Cu), silver (Ag), and gold (Au)

Copper (Cu)

• Reddish-colored metal
• Excellent electrical and thermal conductor, surpassed only by silver and gold
• Important in electrical wiring, resistant to corrosion
• Forms cuprous (Cu⁺) and cupric (Cu²⁺) salts.

Cuprous Ion (Cu⁺)

• Undergoes disproportionation : 2H₂O₂ → 2H₂O + O₂
• Insoluble precipitates (white, except Cu₂S-black, and Cu₂O-brick red)

Cupric Ion (Cu²⁺)

• Maximum oxidation state of copper
• Important component of hemocyanin and cytochrome oxidase
• Hemocyanin is found in crustaceans and is blue when oxygenated, and colorless when deoxygenated
• Found in cytochrome oxidase that assists in energy production (via electron transport system)

Copper (Cu) Alloys

• Metal alloys of copper, commonly bronze and brass.

Copper (Cu) Pharmacologic Actions

• Protein precipitant (heavy metal)
• Enhances iron utilization

Copper (Cu) Toxicity: Wilson's Disease

• Rare, autosomal recessive disorder
• Copper accumulation in the liver, brain, and cornea
• Manifests as Kayser-Fleischer ring in the cornea.

Copper (Cu) Toxicity Antidote

• D-Penicillamine (Cuprimine®): primary chelator used in copper toxicity

Copper (Cu) Deficiency: Menkes Disease

• Caused by mutations in the ATP7A gene, which regulates copper metabolism.
• Affects male infants
• Copper abnormally low in the liver and brain, but high in the kidneys and intestinal lining

Copper (Cu) Compounds and Uses:

• Copper acetoarsenite (Paris Green): Insecticide
• Cupric Sulfate (CuSO₄): Blue vitriol, antidote for phosphorus poisoning, emetic, used in swimming pools as algaecide and fungicide.

Silver (Ag)

• Latin: Argentum
• Common salts are insoluble or slightly soluble in water (except nitrate and fluoride)
• Oligodynamic action: precipitates proteins and chlorides in tissues
• Used in ophthalmology, as antiseptics (e.g., mild silver protein), and in topical formulations

Silver (Ag) Properties

• Soft, ductile, and malleable
• Fine silver (99.9% purity): too soft, often alloyed with other metals for strength and durability (e.g., Sterling silver)
• Silver nitrate (AgNO₃): used historically in ophthalmology to treat ophthalmia neonatorum, still used to cauterize tissues. Some compositions are used in disinfectants and in indelible inks

Silver Nitrate (AgNO₃)

• Lunar caustic, Lapis infernalis
• Component of indelible inks
• Used in ophthalmic solutions to treat warts and gonorrhea (ophthalmia neonatorum); replaced by other ointments
• Toughened silver nitrate compositions are made by adding 5% silver chloride to the silver nitrate.

Silver Proteinates

• Mild silver protein (Argyrol): topical antiseptic
• Strong silver protein (Protargol): topical antiseptic for external use
• Colloidal silver protein (Collargol): general germicide

Gold (Au)

• Latin: Aurum
• King of metals (most expensive and precious).
• Most malleable metal
• Excellent conductor of electricity

Gold Toxicity: Gold Dermatitis

• British Anti-Lewisite (BAL), dimercaprol, is used to treat heavy metal poisoning (arsenic, gold, copper, and mercury)

Gold (Au) Dissolving Agents

• Aqua regia (3 HCl : 1 HNO₃)
• Selenic acid is a single acid to dissolve gold

Gold Compounds: Disease-Modifying Antirheumatic Drugs (DMARDs)

• aurothioglucose (IM): Treatment for adult and juvenile rheumatoid arthritis (RA)
• auranofin (oral): Decreases inflammation in arthritis, improves morning stiffness and pain/swelling, and may increase grip strength

Group 1A: Alkali Metals

Hydrogen (H₂)

• Diatomic gas at standard conditions; colorless, odorless, tasteless, non-toxic, highly combustible
• Most abundant chemical element in the universe (around 75%)
• Used in the Haber process to produce ammonia
• Inflammable air = hydrogen
• Lightest element

Hydrogen Isotopes (protium, deuterium, tritium)

• Protium is the most common, stable isotope
• Deuterium is a heavy isotope used as a solvent in NMR spectroscopy
• Tritium is a radioactive isotope used in some types of safety signs and in biochemical research

Water (H₂O)

• Universal solvent
• Maximum density at 4 °C
• Chemically stable.
• Readily acts as a ligand, acid/base, or oxidizing/reducing agent
• Room temperature: 25 °C
• Density: 0.994 g/cm³

Types of Water

• Water of crystallization, hydration, zeolite water, lattice water
• Natural/mineral water (containing dissolved minerals)
• Carbonated water (with CO₂ content) - Chalybeate (containing iron), Lithia (slightly radioactive), Saline (containing salts), Sulfur (containing sulfur), and Siliceous (containing silica compounds) water

Water Hardness

• Temporarily hard: contains primarily calcium and magnesium bicarbonate (removable by boiling)
• Permanently hard: contains primarily calcium and magnesium sulfate/chloride (removable by ion exchange resin)

Hydrogen Peroxide (H₂O₂)

• Used as a treatment for Vincent's gingivitis (severe form)
• Mouthwash, antiseptic
• Hair bleaching, cosmetic use 

Lithium (Li)

• Lightest of all metals,
• Highly reactive metal
• Stored under oil or coated with petrolatum
• Teratogenic effect (e.g., Ebstein's anomaly, affecting the tricuspid valve of the heart)

Sodium (Na)

• Major extracellular cation
• Stored under kerosene
• Used to optimize pharmaceutical formulations and promotes water retention.
• Aldehyde and ketones can be distinguished with Na2CO3 and Copper Sulfate.

Sodium Acetate (CH₃COONa)

• Diuretic, urinary, and systemic alkalizer

Sodium Bicarbonate (NaHCO₃)

• Baking soda
• Major extracellular anion
• Urinary/systemic alkalizer
• Carbonating agent

Sodium Bromide (NaBr)

• Treatment/prophylaxis for bipolar disorder
• Source of phosphorus in hypophosphatemia, used in hypercalcemia; urinary acidifier
• Necessary for activation of Methamelamine

Sodium Phosphate

• Dibasic/monobasic/tribasic salts used generally to clean glass equipment
• Treatment for hypercalcemia
• Used as a cathartic agent

Sodium Borate (Na₂B₄O₇•10H₂O)

• Borax: Use as an eyewash and buffer and water softener

Sodium Carbonate (Na₂CO₃)

• Anhydrous, decahydrate: used as a carbonating agent
• Table salt, rock salt, sea salt, solar salt

Sodium Citrate (Na₃C₆H₅O₇)

• In vitro: anticoagulant
• In vivo: systemic/urinary alkalizer, expectorant, laxative

Sodium Fluoride (NaF)

• Fluoride ion: highly corrosive; used in glass etching
• Causes painful, slow-healing burns, toxic.

Sodium Gluconate (NaC₆H₁₁O₇):

• Electrolyte replenisher (less irritating than chloride salts)

Sodium Nitrate (NaNO₃)

• Saltpeter: Tooth-desensitizing agent
• Use in some oxidizing agents

Sodium Perborate

• Mild disinfectant and deodorant

Sodium Sulfite (Na₂SO₃)

• Dihydrate: Used as an analytical reagent for Karl Fischer reagent

Sodium Thiosulfate (Na₂S₂O₃)

• Hypo-chlor: Photo-copier's hypo
• Good reducing agent, and antioxidant

Potassium (K)

• Major intracellular cation,
• Potassium salts are used in many medicinal and industrial applications.

Potassium Acetate (CH₃COOK)

• Use: systemic and urinary alkalizer

Potassium Bicarbonate (KHCO₃)

• Use: Carbonating agent

Potassium Bitartrate (KC₄H₅O₆)

• Cream of tartar, acid potassium tartrate
• Ingredient in baking powder

Potassium Carbonate (K₂CO₃)

• Potash, pearl ash, salt of tartar, salt of wormwood

Potassium Chloride (KCl)

• Potassium replenisher
• Used in Ringer's and Lactated Ringer's solutions

Potassium Citrate (K₃C₆H₅O₇)

• Systemic alkalizer, expectorant, diaphoretic, osmotic diuretic

Potassium Gluconate (KC₆H₁₁O₇)

• Electrolyte replenisher

Potassium Hydroxide (KOH)

• Caustic potash, potash lye: Delquescent, strong base used in medicine
• Use: saponifying agent, some soft soap formulations, good CO₂ absorber, some O₂ therapy/metabolic tests (e.g. soda lime)

Potassium Iodide (KI)

• Source of iodide in table salt to prevent goiter
• Treatment of hyperthyroidism, preparation for thyroid surgery
• Solubilizer for iodine
• Use in some disease treatments and diagnostic tools

Potassium Nitrate (KNO₃)

• Saltpeter: tooth-desensitizing agent, strong oxidizing agent, historical use as antithyroid agent

Potassium Permanganate (KMnO₄)

• Mineral chameleon (deep purple color)
• Strong oxidizing agent
• Used to treat bromhidrosis (body odor), mycosis (fungal), and poison ivy/oak dermatitis

Potassium Metabisulfite (K₂S₂O₅)

• Good reducing agent, antioxidant
• Buffering agent

Potassium Potassium Phosphate

• Used in hypercalcemia treatment

Potassium Sorbate

• Preservative and antimicrobial agent

Rubidium (Rb) and Cesium (Cs)

• Similar to potassium, used in cardiac imaging and density/gradient configuration

Ammonium (NH₄)

• Pseudo-alkali metal, similar to Group 1A
• Often preferred to alkali bases
• Ammonia (aq) is an important chemical in medicine.

Ammonium Carbonate ((NH₄)₂CO₃)

• Ammonia crystal, sal volatile, ammonia sesquicarbonate, Preston salt, hartshorn 

Ammonium Chloride (NH₄Cl)

• Sal ammoniac, salmiac, muriate of ammonia
• Use: osmotic diuretic, systemic acidifier, expectorant, urinary acidifier

Ammonium Alum (and Potassium Alum)

• Tawas: astringent and antiperspirant
• Strong ammonia solutions are used for chemical purposes, in making ammonia water, and in aromatic ammonia spirit.

Boron Family (Group 3A)

• Consists of boron (B), aluminum (Al), gallium (Ga), indium (In), and thallium (Tl)

Aluminum (Al)

• Most abundant metal in Earth's crust
• 3rd most abundant metal (after oxygen and silicon)
• Bauxite: common ore of aluminum
• Aluminum oxide (Al₂O₃) and hydroxides are amphoteric
• Toxicity by inhalation of aluminum oxide dust leads to Shaver's disease

Boron (B)

• Metalloid
• Diagonally related to silicon
• Shares comparable atomic radii and ionic radii
• Toxic

Boric Acid (H₃BO₃)

• Solid, soluble in water and alcohol.
• Three forms: scales, crystals, and powder
• Antimicrobial action

Other Boron Family uses and compounds

• Boric Acid (H₃BO₃): Preservative, eye wash, antiseptic
• Aluminum Subacetate Topical: Excipient, astringent
• Aluminum Silicates: Suspending agent (e.g., Bentonite magma)
• Aluminum Hydroxide Gel: Antacid, minor bruise swelling relief, and foot-sweat reducer
• Aluminum Silicates: (e.g., bentonite): internal use (antidiarrheal, intestinal adsorbent/demulcent), and dusting powder
• Aluminum Chloride: Astringent, antiseptic, antiperspirant
• Alum: (e.g., Ammonium alum, potassium alum): Use in astringents, antiperspirants, and some preparations. 

Explore the characteristics of Group 2B volatile metals, including zinc, cadmium, mercury, and copernicium. This quiz covers zinc's properties, its role in various applications, and its pharmacological actions. Test your knowledge on the essential functions and uses of zinc and other transition metals.