Chemistry Experiments, Q, R¶

2. In this document, "concentrated acid", or any other substance, refers to the concentration supplied by chemical suppliers, e.g. concentrated hydrochloric acid is 36% w / w, unless otherwise specified.

3. For all experiments, unless otherwise instructed, use either:

3.1 a 5 mL of solution, or

3.2 a test-tube filled to the depth of a finger width, or

3.3 the powder on a little finger nail, or

3.4 a piece of solid chemical the size of half a dried pea, or

3.5 no more than one third of a test-tube of any solution.

4. Do not make gas jars full of gas for demonstration purposes.

Use test-tubes with stoppers to collect gases.

Quartz¶

Silica, SiO₂ source

Quartz: 35.14.0

Construct molecular models (quartz): 11.2.3

Silicon: 12.10.0

Voltage from mechanical stress to crystals, piezoelectricity: 32.1.2.1

Quassin¶

Quassin, C₂₂H₂₈O₆, nigakilactone D, a quassinoid febrifuge, vermicide, bitter tonic source

It occurs in Surinam Quassia wood, (Quassia amara).

Quercetin¶

Quercetin, C₁₅H₁₀O₇, [(C6-(C3-(C6], flavonol glycoside, a pentahydroxyflavone, polyphenolic flavonoid, the most active of the flavonoids. source

It is a yellow powder, antioxidant in many plants, a phytoestrogen, are used for vegetables in a good diet and food additive.

Many medicinal plants have high quercetin content, anti-inflammatory activity. by inhibiting release of histamine.

Quercetin, antioxidant activity, anticancer, inhibits fatty acid synthase phytochemical.

It causes the colouring found in the skins of apples and red onions.

Quercetin may protect against heart disease and cancer, prevents damage to LDL cholesterol, antioxidant, natural anti-histamine.

It is anti-inflammatory, anti-cancer, but unproved necessary addition to dietary supplements.

It occurs in berries, red grapes, citrus fruit, tomato, and in broccoli.

Do not take quercetin if taking prescribed medicines, are pregnant or breast feeding or have liver disease.

Quinacrine¶

Quinacrine, C₂₃H₃₀ClN₃O, Mepacrine, Atabrine, is an acridine derivative, bright yellow powder, odourless. source

It can be toxic, kills protozoa, antihelminthic, used to treat giardiasis.

During World War II in the pacific region it was widely used as antimalarial drug known as Atebrine.

It was unpopular with Australian troops fighting in Papua New Guinea, because it turned skin yellow it and was supposed to make men infertile.

Atebrine was generally replaced by chloroquine, C₁₈H₂₆ClN₃, but (Plasmodium falciparum) has since developed resistance to it. source

Quinidine¶

Quinidine, (C₂₀H₂₄N₂O₂), Quinoline Alkaloid source

Quinidine, Chinidin, Pitayine, Cin-quin, optical isomer of quinine, antimalarial, anti-arrhythmic in the heart, dampens the excitability of cardiac and skeletal muscles, decreases conduction velocity of nerve impulses.

It occurs in Chinchona tree bark.

Quinine¶

Quinine, (C₂₀H₂₄N₂O₂), Quinoline Alkaloid source

Quinine, Chinin, Chinine, Qualaquin, irritant, is an alkaloid from cinchona tree bark, antimalarial drug, active ingredient, mild antipyretic.

It is an aanalgesic, so it is used in common cold preparations to treat idiopathic leg cramps.

Nowadays, it is used as a bitter and flavouring agent in Schweppes Indian Tonic Water.

It occurs in cinchona tree extracts.

See: Quinine.

Quinoline¶

Quinoline, (C₉H₇N), Quinoline Alkaloid source

Quinoline, heterocyclic aromatic organic compound, colourless hygroscopic liquid, strong odour, if exposed to light yellow then brown.

It is slightly soluble in cold water, and is used as a flavouring ingredient.

It occurs in Mentha, cocoa, black tea, and in scotch whisky.

Quinoline yellow, (C₁₈H₁₁NO₂), mixture of dyes based on quinoline, quinophthalone, solvent yellow, erio chinoline yellow 4G source

E104, azo dye is based on quinoline, bright yellow colour, possible health risk is dermatitis, and is used in lipsticks.

Radium, Ra¶

Radium, Ra

Radium, Table of the Elements

Radium, RSC

Radium (Latin radius, 'spoke'), is an alkaline earth metal.

Radium is a radioactive alkaline earth metal, extracted from pitchblende, uraninite, used in cancer therapy, and as a radioactive resource.

Radiation dose from entry of radioactive materials into the body: 7.2.2

Atomic number: 88, Relative atomic mass: 226.025, RD: 5.0, MP: 700 oC, BP:1140 oC

Specific heat capacity: 121 J kg-1 K-1

Radon, Rn¶

Radon, Rn

Radon, Table of Elements

Radon, RSC

Radon, Rn (from Ra radioactive decay), in former health spas, Rn-222, Group 18, was te last noble gas found.

Radon is a non-metal noble colourless water-soluble gas at room temperature and pressure.

Rn2 is formed by decay of radium-226, usually under granite, where it may be a health habit to people living in granite houses.

Radon has few compounds and is used in radiotherapy.

Atomic number: 86, Relative atomic mass: (222), RD: 4.4 (211 K), MP: -71 oC, BP: -61.8 oC

Specific heat capacity = 92 J kg-1 K-1

Rapanone¶

Rapanone, C₁₉H₃₀O₄, is a quinone, benzoquinone, dihydroxy-1,4-benzoquinone, and is antihelmintic. source

It occurs in (Rapanea maximowiczii), Aegiceras, and in Oxalis.

Raphanin¶

Raphanin, C₆H₉NOS₂, sulphoraphene, toxic, antioxidant, antibacterial, and is used in Chinese medicine. source

It occurs in seed of Radish, (Raphanus raphanistrum subsp. sativus), Brassicaceae, and in root vegetables.

Rayon¶

Rayon, viscose, is made from cellulose products and wood.

Rayon polymer: 3.8.14

Rayon, burning test: 4.3.21

Organic builders in washing powders: 12.6.8

Prepare rayon: 3.3.8

Triboelectric series: 31.1.02 See: Negative polarity, 29. Rayon

Reactions of:¶

Rate of reaction, k: 17.1.11

Recycle¶

Recycle chemicals: 3.4.7 See: 1.3 Recycle

Plastics recycling code, recycling symbols: 3.4.0

Recycle copper: 12.7.8

7.9.31, Recycle heavy metals safety, (Experiments)

Recycle silver: 12.10.1, (See: 6.)

Redox¶

Redox reactions, reduction-oxidation reactions

Redox indicators, List of redox indicators: 1.21

Redox reactions: 12.2.9

Redox reactions, Disproportionation: 17.7.16

Reduce¶

Reduce, reducing, reductants, reduction

In an electrolytic cell, oxidation occurs at the positively charged anode and reduction occurs at the negatively charged cathode.

Reduce carbon dioxide with burning magnesium: 3.1.1

Reduce copper oxide with natural gas methane: 16.5.1.64

Reduce metal compounds: 10.10.0

Reduce metal compounds

Reduce nitrate to ammonia: See 4.1

Reducing agent, Reactions of metals as reducing agents: 12.14.0

Reducing agent, Separate metals by reduction of metal oxides: 10.10.0

Reducing agents, Oxidizing agents and reducing agents: 15.4.0

Reducing sugars, tests for breakdown of starch to reducing sugars: 9.3.6

Reductants (reducing agents): 15.3.3

Reductants, List of chemical reductants: 1.22

Reduction reactions, gain of electrons: 16.1.3

Tests for reducing sugars, Benedict's test for reducing sugars: 9.4.1

Tests for reducing sugars, Fehling's test for reducing sugars: 9.5.0

Rescinnamine Rescinnamine, (C35H42N2O9), Vinca Alkaloid, anti-hypertensive, tranquillizer, widely used in folk medicine¶

Rescinnamine Rescinnamine, (C₃₅H₄₂N₂O₉), Vinca Alkaloid, anti-hypertensive, tranquillizer, widely used in folk medicine source

It occurs in Poison devil's-pepper (Rauvolfia vomitoria).

Reserpine¶

Reserpine, (C₃₃H₄₀N₂O₉), Indole Alkaloid source

Reserpine, indole derivative alkaloid, monoterpenoid indole alkaloid, corynanthe type alkaloid, anti-hypertensive, antipsychotic

It was used to control high blood pressure, tranquillizer, but nowadays rarely used.

It occurs in Indian snakeroot (Rauvolfia sepentina).

Resins¶

Resin, (Latin: resina, Resinum 'from a pine')

Resins are hard, sticky, inflammable, usually aromatic substances, insoluble in water, usually collected by incisions into fir and pine trees.

They contained organic polymers and terpenoids, e.g. alpha-pinene, beta-pinene, limonene. terpinolene, caryophyllene and resin acids.

Synthetic resins, so-called, because they at first resembled natural resins, are used to make plastics are thermosetting or thermoplastic.

Rosin, colophony, gum rosin, colophonium, Greek pitch, is a solid amber residue made by the distillation of turpentine from pine stumps.

Rosin is used for adhesives, varnishes, violin bows, and contains diterpenes.

Rosins are used on the bows of violins and other stringed instruments.

Resin, ion exchange resin, anion exchange resin ("Permutit"), DOWNEX AGI-X8

Melamine-formaldehyde resins, (MF): 16.7.6.1 Cyanamides

Remove water hardness: 12.5.5

Resins and gums: 3.0.0

Resin Identification Code, Plastics recycling code: 3.4.0

Zeolite: 18.1.28

Water softening using ion exchange resin: 12.2.15

Resveratrol¶

Resveratrol, C₁₄H₁₂O₃, plant polyphenol, a stilbenoid, a glycoside, a resorcinol, polyphenolic phytoalexin, antioxidant. source

It is anti-diabetic, neuroprotective, antibacterial, antifungal.

It may be used to treat diabetes, atherosclerosis, aging.

It occurs in seeds of transgenic oilseed rape (Brassica napus), Japanese knotweed, red grapes skin, Polygonum, Picea, Pinus, and in (Eucalyptus wandoo) wood.

Retamine¶

Retamine, (C₁₅H₂₆N₂O), Quinolzidine Alkaloid source

Retamine, Hydroxysparteine, is hypotensive, and diuretic.

It occurs in Genista.

Retene¶

Retene, C₁₈H₁₈, methyl isopropyl phenanthrene, environmental hazard, polycyclic aromatic hydrocarbon, cytotoxic source

It occurs in tars from distillation of resinous woods, and in wood pulp effluent.

It indicates conifer forest fires.

Reticuline¶

Reticuline, (C₁₉₀H₂₃NO₄), Isoquinoline Alkaloid source

Reticuline, benzylisoquinoline alkaloid, coclanoline, alkaloid precursor, (precursor of morphine)

It occurs in Papaver, Cryptocarpa, and in Romneya.

Retronecine¶

Retronecine, (C₈H₁₃NO₂), Pyrolizidine Alkaloid, senecifolinene, pyrolizidine derivative, non-ester, may cause liver damage from excessive consumption. source

It occurs in (Borago officinalis), (Senecio vulgaris), (Tussilago farfara), (Heliotropium europaeum), (Echium plantagineum), and in (Crotalaria retusa).

Rhaponticin¶

Rhaponticin, C₂₁H₂₄O₉, rhapontin, ponticin, a stilbenoid, antifungal. source

It occurs in (Polygonum multiflorum), rhubarb, (Rheum rhabarbarum), and in Eucalyptus.

Rhein¶

Rhein, C₁₅H₈O₆, cassic acid, rhubarb yellow, rheic acid, glucorein (rhein-8-glucoside), yellow needles or powder, cathartic source

It occurs in Rhubarb, (Rheum rhabarbarum), Polygonaceae.

Rhenium, Re¶

Rhenium, Re

Rhenium, Table of the Elements

Rhenium, RSC

Rhenium (Latin: Rhenus 'Rhine river')

Rhodamine dyes Rhodamine B, C28H31ClN2O3¶

Rhodamine dyes Rhodamine B, C₂₈H₃₁ClN₂O₃ source

Rhodamine 6G, C₂₈H₃₁N₂O₃Cl source

Rhodamine 123, C₂₁H₁₇ClN₂O₃ source

Rhodamine B cation, Rhodamine B(1+), Rhodamine 610, C₂₈H₃₁N₂O₃⁺, cationic fluorescent dye, xanthene dye. source

Rhodinol¶

Rhodinol, C₁₀H₂₀O, monoterpene alcohol, floral fragrance source

It occurs in citronella oil, and in lemon grass.

Rhodium, Rh¶

Rhodium, Rh

Rhodium, Table of the Elements

Rhodium, RSC

Rhodium, Rh, (Greek rhodos 'rose', from pink colour of Rh compounds), white to blue-white, hard, ductile, malleable metal

It is used in jewellery and electroplating.

C₂₈H₃₁N₂O₃Cl. Rhodium trichloride source

Catalytic converter in a motor vehicle: 18.6.1

Rhodopin¶

Rhodopin, C₄₀H₅₈O, a carotenoid pigment, carotenol, tertiary alcohol source

It occurs in phototrophic bacteria and in Afifella.

Rhoeadine¶

Rhoeadine, (C₂₁H₂₁NO₆), rheadine, rhoeadan alkaloid, possibly antitumour, folk medicine, expectorant, sedative. source

It occurs in (Papaver rhoeas).

Isoquinoline Alkaloid

Rhombifoline¶

Rhombifoline, (C₁₅H₂₀N₂O), rhombifoline, butenylcytisine source

It occurs in Genista, Ammodendron, Thermopsis, and in (Laburnum anagyroides).

Quinolzidine Alkaloid

Riboflavin¶

Riboflavin, C₁₇H₂₀N₄O₆, (Latin flavus 'yellow')br Food additive E10, 1 Riboflavin, Riboflavin-5'-phosphate(vitamin B2), (In green vegetables, eggs, milk, liver), colour: orange to yellow), (in margarine). source

Cassava tubers and cocoa "beans" contain riboflavin.

Riboflavin, vitamin b2, Lactoflavin, Riboflavine, orange-yellow crystalline compound, a heat-stable and water-soluble flavin is a growth promoting factor.

It is the precursor of the coenzymes flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD), and is important for metabolism.

It is essential for healthy skin, nails, and hair, and it is used to treat vitamin b2 deficiency.

It occurs in babassu palm, burdock, pepper, (capsicum), Vitamin b2 complex vitamins in cereals, milk, eggs, malted barley, liver, kidney, heart, leafy vegetables.

It occurs freely in eye retina and urine.

E101 Riboflavin, Riboflavin-5'-phosphate, (vitamin b2), occurs in green vegetables, eggs, milk, liver), (colour: orange to yellow) (margarine).

Diet: 15.0, Bananas

Flavonoids, (Bioflavonoids)

Freezing, thawing and cold storage of meat: 19.2.5

Lost nutrients in food: 19.2.7

Pasteurization of milk: 19.2.10

Poultry composition: 12.4

Regular cows milk, fresh milk, full cream milk, whole milk: 16.2.1a

Test the cooking water of boiled vegetables: 19.2.12

Ricinine¶

Ricinine, (C₈H₈N₂O₂), Pyrrolidine and Piperidine Alkaloid source

Ricinine, Ricidine, Ritsinin, pyridine derivative, pyridine alkaloid, pyridone, nitrile, bitter white crystals.

It may cause toxic burning feeling in mouth and throat, nausea, vomiting, severe pain in stomach, diarrhoea, reactions, hepatic and renal damage, death.

It is used as alkaloid marker for poisonous lectin ricin, e.g. in urine, toxic alkaloid, insecticidal.

It occurs in (Ricinus communis), castor seeds and leaves.

Castor oil, ricinoleic acid: 16.3.6.4.

Riddelline¶

Riddelline, (C₁₈H₂₃NO₆), Pyrrolizidine Alkaloid source

Riddelline, is a diester of retronecine (C₈H₁₃NO₂), and a possible carcinogen. source

It occurs in (Senecio riddelli), (Senecio vulgaris), (Acobaea vulgaris), Crotalaria, and in Amsinckia.

Ridentin¶

Ridentin, C₁₅H₂₀O₄, a germacrane sesquiterpenoid. cytotoxic, antitumour. source

It occurs in Artemisia.

Rishitin¶

Rishitin, sesquiterpene, C₁₄H₂₂O₂, polyol, terpenoid compound, antifungal, bacteriocidal, phytotoxic, phytoalexin. source

It is produced by tubers of (Solanum tuberosum) infected by Phytophthora fungi.

Rituximab¶

Rituximab, C₆₄₁₆H₉₈₇₄N₁₆₈₈O₁₉₈₇S₄₄, ia a monoclonal antibody medication. source

It is used to treat non-Hodgkin lymphoma, and other conditions, by slow injection into a vein.

It works against the CD20 antigen on the surface of normal and malignant immune system B lymphocytes, to trigger cell death.

Side effects may include easy bruising, decrease in the amount of urine or unusual tiredness.

CHOP, chemotherapy used or treatment of non-Hodgkin lymphoma.

Cyclophosphamide, is an alkylating agent.

Hydroxydaunorubicin, (doxorubicin, adriamycin), is an intercalating agent.

Oncovin (vincristine), prevents cells from duplicating by binding to the protein tubulin.

Prednisone or Prednisolone, are corticosteroid component of R-CHOP₂₁. source

Rochelle salt¶

Rochelle salt, KNaC₄H₄O₆.4H₂O, potassium sodium tartrate tetrahydrate, Seignette salt source

Seidlitz powder is a double salt of tartaric acid.

It has a saline cooling taste as a laxative, and the large deliquescent monoclinic crystals are piezoelectric and used in "crystal" phonograph pickups.

Rochelle salt: E337

Prepare Fehling's solution: 9.5.1

Tests for proteins, biuret test: 9.4.2

Piezoelectricity: Rochelle salt

Rocks¶

Rocks and minerals: 35.1.0

Minerals: 35.2.0

Igneous rocks: 35.2.1

Metamorphic rocks: 35.3.7

Sedimentary rocks: 35.4.5a

Roentgenium, Rg¶

Roentgenium, Rg

Roentgenium, Table of the Elements

Roentgenium, RSC

Roentgenium (William Roentgen, 1845-1923, Germany, discovered X-rays), radioactive, transuranic (atomic number > 92)

Rose bengal¶

Rose bengal, C₂₀H₄Cl₄I₄O₅, fluorochrome, histological dye, xanthene dye, organic potassium salt, is related to fluorescein, C₂₀H₁₂O₅. source

The sodium salt, C20H2(Cl4I4Na2O5, is used to treat eye disorders.

It is used as a stain and to treat cancers.

Rotundine¶

Rotundine, (C₂₁H₂₅NO₄), Tetrahydropalmatine, Berberine Alkaloid source

It is a selective dopamine D1 receptor agonist, analgesic, adrenergic agent, non-narcotic analgesic, antiprotozoal, anti-arrhythmic, sedative, tranquillizer.

It occurs in (Stephania sinica) and is widespread in China.

Rhodoxanthin¶

Rhodoxanthin, C₄₀H₅₀O₂, xanthophyll carotenoid, carotenoid pigment source

Food additive: E161f

Rhodoxanthin occurs in the yew tree, (Taxus baccata).

Rose oxide¶

Rose oxide, C₁₀H₁₈O, monoterpenoid, is a fragrance chemical. source

It occurs in roses oil, lychee, and in Gewurztraminer wines.

Rubidium, Rb¶

Rubidium, Rb

Rubidium, Table of the Elements

Rubidium, RSC

Rubidium, Rb, (Latin rubidus red), two red lines in spectrum), is a silver-white, very reactive, alkali metal.

It occurs in pegmatites, lepidolite and pollucite.

Ruthenium, Ru¶

Ruthenium, Ru

Ruthenium, Table of the Elements

Ruthenium, RSC

Ruthenium, Ru, (LatinRuthenia 'Russia'), silver-white, rare similar to platinum, catalyst, hardens alloys.

It is used in electrical contacts, platinum alloys, jewellery electroplating for "high-tech grey-black look".

Ruthenium (III chloride, Ruthenium (III) chloride hydrate, Ruthenium carbonyl

Rutherfordium, Rf¶

Rutherfordium, Rf

Rutherfordium, Table of the Elements

Rutherfordium, RSC

Rutherfordium (Earnest Rutherford, 1971-1937, New Zealand, later UK)

Rutherfordium is radioactive, transuranic (atomic number > 92).

Rubixanthin¶

Rubixanthin, C₄₀H₅₆O, xanthophyll carotenoid, xanthophyll pigment, Natural Yellow 27, red-orange pigment, former food colourant (E161d). source

It occurs in Rose hips (Rosa canina) and Apricot (Prunus armeniaca), Rosaceae.

Rutaecarpine¶

Rutaecarpine, (C₁₈H₁₃N₃O), rhetine, a pyridopyrimidine, inhibits platelet aggregation, hypotensive, vasoldilator, with strong bitter taste, is in Chinese medicine. source

It occurs in (Tetradium ruticarpum), (Evodia rutaecarpa), and in (Hortia arborea).

Indole Alkaloid

Rutin¶

Rutin, C₂₇H₃₂O₁₆, sophorin, a tetrahydroxyflavone, Rutin, sophorin, bioflavonoid is a yellow or greenish-yellow, needle-shaped crystals. source

Antioxidant, strengthens capillaries to prevent bruising or bleeding, anti-inflammatory.

It prevents fat deposits in the arteries, reduces cytotoxicity of oxidized LDL-cholesterol, utilizes vitamin C to maintain collagen.

It occurs in many plants, fruits and vegetables, buckwheat, Carpobrotus, (Sophora japonica), (Ruta graveolens), Citrus, olive, lovage, dock, dill, and in fennel.

Do not take rutin if pregnant or breastfeeding.

Rutin hydrate, C₂₇H₃₀O₁₆.xH2O, polyphenolic flavonoid, antioxidant, a NO scavenger, free radical scavenger, is protection against carcinogenesis. source

Strontium¶

Strontium Table of the Elements

Strontium RSC

Strontium, Sr (former Strontia region, Scotland, where Strontium first found), alkaline earth metal, AAS solution.

Toxic if ingested, surface layer corrosive to skin and eyes.

Strontium with water forms hydrogen gas that may explode if mixed with air.

Strontium, do not mix with sulfur or phosphorus, because of dangerous exothermic reaction.

Strontium, Sr, silver white metallic element, in minerals celestine (SrSO₄), strontianite (SrCO₃), and spring water, similar properties to calcium. source

Strontium salts used for crimson flame in fireworks, after nuclear explosion fallout contains 90Sr that can be absorbed in human bone.

Strontium chloride in toothpaste for sensitive teeth, e.g. "Sensodyne".

Strontium is harder to cut than sodium, use calcium as cheaper alternative.

For schools, purchase only small quantity of strontium and store in tightly-sealed container, give students only few grains per activity.

Atomic number: 38, Relative atomic mass: 87.62, RD 2.54, MP = 800 oC, BP = 1300 oC.

Specific heat capacity: 0.3 J kg-1 K-1.

Strontium minerals

Strontium toxicity: 4.15

Tests for strontium: 12.11.3.28

Strontium compounds

Reactions of strontium compounds: 12.12.0

Strontianite, SrCO₃, strontium carbonate source

Strontium carbonate, SrCO₃, in strontianite mineral, harmful if ingested, skin irritant source

Strontium carbonate, Low cost: from pottery supplies stores

Strontium (II) chloride, SrCl₂, strontium dichloride (detected with flame test), harmful if ingested source

Strontium chloride hexahydrate, SrCl₂.6H₂O, For 0.1 M solution, 26.7 g in 1 L water source

Strontium chloride (powder)

Strontium fluoride

Strontium hydroxide, harmful if ingested, skin irritant, corrosive

Strontium nitrate, Sr(NO₃)₂, AAS Solution, harmful if ingested, explosive mixtures with combustibles of organic compounds source

Strontium sulfate, SrSO₄, celestine source

This page was generated automatically from the original page on John Elfick's School Science Lessons website. If something looks wrong, please check the original.