Science Olympiad - Division C - Forensics: Powders

Sodium Acetate (NaC2H3O2 or NaCH3CO2)

fine white powder; very soluble (quick); pH = 9; Conductivity: high; flame = yellow; used as additives in food, industry, concrete manufacture, heating pads and in buffer solutions. Medically, sodium acetate is an important component as an electrolyte replenisher when given intravenously.

Sodium Chloride (NaCl)

white crystal, uniform crystals; very soluble (quick); pH = 6 Conductivity: high; flame = yellow/orange; also called "table salt"; used as a food preservative and as a seasoning to enhance flavor. Sodium chloride is also used in manufacturing to make plastics and other products, and it is used to de-ice roads and sidewalks.

Sodium Hydrogen Carbonate (sodium bicarbonate) (NaHCO3)

pure white fine powder; soluble (average time to dissolve); pH = 8; Conductivity: high; HCl: vigorous reaction/gives off CO2; also called "baking soda"; used as a leavening agent in baking (makes baked goods rise), neutralizes odors, cleaning agent, whitening agent, and as an antacid to soothe heartburn.

Sodium Carbonate (Na2CO3)

white fine powder; soluble (long time to dissolve); pH = 9.5; Conductivity: high; HCl: vigorous reaction/gives off CO2; also called "soda ash"; primary uses are as water softener, food processing aid, pH modifier, chemical swimming pool chemical and electrolyte; also used in the glass industry, ceramics industry, soap industry, detergent industry, paper industry, and cardboard industries.

Lithium Chloride (LiCl)

pure white fine powder, clumpy; very soluble (quick); pH = 6; Conductivity: high; flame = deep pink/red; used to manufacture lithium metal, used in automotive parts as a brazing flux for aluminum, used as a desiccant to dry fluxes of air, used as one of the most well-known mood stabilizers with antisuicidal effects, is currently being utilized as an agent for acute mania and as a maintenance treatment in bipolar disorder (BD), another application is as a flame colorant for producing dark crimson flames in fireworks.

Potassium Chloride (KCl)

white crystal, clumpy; very soluble (quick); pH = 6; Conductivity: high; Flame = purple; also called "potash"; used as a fertilizer, in medicine, in scientific applications, domestic water softeners (as a substitute for sodium chloride salt), and in food processing.

Calcium nitrate (Ca(NO3)2)

yellowish/whitish round crystals; partially soluble; pH = 6; Conductivity: high; NaOH: turns a bluish/whitish milky color; main use is as a fertilizer in agriculture but is also used in explosives and pyrotechnics and in the wastewater treatment industry, concrete industry, and latex industry.

Calcium sulfate (CaSO4)

white/colorless powder; low solubility; pH = 6; Conductivity: low, Iodine test: no reaction; HCl test: fizzes (not bubbles)/turns milky white; also called "gypsum" or "plaster of Paris"; used in making drywall (construction), dentistry to make plaster molds, and food industry as a coagulant (tofu).

Calcium carbonate (CaCO3)

fine white powder; not soluble; pH = 6; Conductivity: low; HCl test: reacts w/ bubbles; also called "chalk", "limestone", or "marble"; Iodine test: no reaction; used as an effective dietary calcium supplement, antacid, phosphate binder, base material for medicinal tablets or as chalk. It also is found on many grocery store shelves in products such as baking powder, toothpaste, dry-mix dessert mixes, dough, and wine.

Cornstarch (polymer of the monomer C6H10O5)

fine white powder; barely soluble (if at all); pH = 6; Conductivity: none; Iodine test: turns blue-black; used as a thickening agent for gravies, marinades, sauces, soups, and casseroles.

Glucose (C6H12O6)

white crystals; soluble; pH = 7; Conductivity: none; NaOH test: no reaction; HCl test: no reaction; Flame = no change; Benedict's test: positive test (rusty orange color); also called "dextrose"; used for blood sugar regulation in diabetics, in commercially prepared food products are as a thickener, sweetener, and humectant (an ingredient that retains moisture and thus maintains a food's freshness) and also widely used in the manufacture of a variety of candy products.

Sucrose (C12H22O11)

white crystals; soluble; pH = 6-7; Conductivity: none; NaOH test: no reaction; HCl test: no reaction; Flame = no change; Benedict's test: negative test; used in foods and soft drinks as a sweetener, in syrup processing, in invert sugar, confectionery, preserves and jams, demulcent, medicinal products, and caramel, and also as a chemical carrier for detergents, emulsifiers, and other derivatives of saccharose.

Magnesium sulfate (MgSO4)

white granular crystals; very soluble; pH = 6; Conductivity: high; NaOH test: precipitate forms; also called "Epsom salt"; used for short-term relief of constipation. It is also used as a soaking solution to relieve minor sprains, bruises, muscle aches or discomfort, joint stiffness or soreness, and tired feet.

Boric acid (H3BO3)

glimmery white crystally grain; soluble; pH = 5.2; Conductivity: none; NaOH test: no reaction; HCl test: no reaction; Flame = green; used as a fireproofing agent for wood, as a preservative, and as an antiseptic. It is also used in the manufacture of glass, pottery, enamels, glazes, cosmetics, cements, porcelain, leather, carpets, hats, soaps, artificial gems, and in tanning, printing, dyeing, painting, and photography.

Ammonium Chloride (NH4Cl)

fine white crystal; slightly reflective; very soluble (quick); pH = 5.5; Conductivity: high; NaOH: gives off ammonia smell; Benedict's: deep indigo; Flame = faint green; used as a nitrogen supply in fertilizers and as an electrolyte in dry cells, and it is also extensively employed as a constituent of galvanizing, tinning, and soldering fluxes to remove oxide coatings from metals and thereby improve the adhesion of the solders.