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Renuzit

Renuzit is a brand of air fresheners produced by the Dial Corporation. The Renuzit brand once included a solvent-based spot remover and cleaner as well.

How air fresheners work

Air fresheners are basically perfume dispensers. In the 1950s, the most popular air freshener was Air Wick, consisting of a perfumed solution in a glass bottle with a large wick that could be raised in the open neck of the bottle. These were not altogether satisfactory, not only because of the hazard of knocking the bottle over and spilling the liquid, but because the wick tended to dry out on the surface.

Early aerosols dispensed perfume oils, leaving a heavy scent in the air.

Modern air fresheners

In the 1960s, consumers responded well to the modern Glade air fresheners introduced by [S. C. Johnson & Son]. Solid Glade was a perfumed vegetable gelatin. Aerosol Glade used an emulsion of perfumed oil and water, which gave the consumer a much more controllable scent that dispersed rapidly. Glade remains the market leader.

Renuzit’s aerosol product was a me-too product. Their solid air freshener, however, was packaged in an attractive extruded plastic cone. This may have worked against Renuzit sales. As the gelatin dries out, the light vacuum-formed shell of a Glade solid air freshener would lose most of its weight, and get discarded. It is not so obvious that the Renuzit freshener is depleted.

More recently, air fresheners have used heat-based convection and even small fans to disperse the fragrance.

Fragrance innovations

Traditionally, the best-selling air fresheners for all companies were heavy floral scents, and “Powder Room”, which aped the fragrance of Johnson & Johnson’s baby powder.

Renuzit introduced a popular fragrance in 1972 which they called Super Odor Killer. The fragrance in SOK was not readily identifiable, because SOK used a blend of perfumes left over when fragrance manufacturers produced a little too much for another company’s orders. This blend was not only good at masking a variety of odors, it could be used at slightly higher fragrance levels without overwhelming the user.

Renuzit was also the first to introduce an air freshener for they kitchen when they brought out “Country Kitchen” cinnamon fragrance in 1976. It proved to be highly popular and was soon copied by competitors.

Cleaner

Renuzit offered a cleaning solvent at one time, sold in 4-ounce steel dispenser cans similar to those used for multipurpose household oil, and in steel quart cans similar to those used for paint thinner. It was apparently a dry-cleaning fluid, possibly 1,1,1-trichloroethane. Manufacture of the product appears to have been discontinued in the early 1970s.

Company History

Renuzit was originally produced by Renuzit Products of Philadelphia. It isn’t clear when that company was founded. They were acquired by Drackett in the late 1960s or early 1970s. When Bristol-Myers sold the Drackett S. C. Johnson & Son in 1992, the Federal Trade Commission ordered Johnson to divest itself within a year of the Renuzit products and certain other products, and not purchase any other company making air fresheners for 10 years. They sold Renuzit to Dial. Johnson petitioned the FTC on September 28, 1995 to end the 10-year restriction, and 3 months later, the FTC agreed.

Urban legend

According to urban legend, the label on a 1995 can of Renuzit air freshener included a deliberately planted phallic image.

In March, 1995, Dial introduced a new label for the Fresh Cut Flowers fragrance of their aerosol air freshener. Within a couple of months, both Dial and retailers started receiving complaints about a phallus that appeared on the can. In fact, the image was that of a tulip stem, which was readily apparent when looking at the same image on the Renuzit LongLast Roomate air freshener.

Dial switched to another photo for subsequent production.

References

• “Clearing the Air About a Label” by Henry Gilgoff in the June 9, 1995 Newsday.

External links

• Official site
• FTC order

Reagent

For a description of a reagent in a chemical reaction, see reactant.

When purchasing or preparing chemicals, reagent describes chemical substances of sufficient purity for use in chemical analysis, chemical reactions or physical testing. Purity standards for reagents are set by organizations such as ASTM International. For instance, reagent-quality water must have very low levels of impurities like sodium and chloride ions, silica, and bacteria, as well as a very high electrical resistivity.

In a broader definition a reagent is any substance used in a chemical reaction. It usually implies a chemical that is added in order to bring about the chemical change.

For example hydrochloric acid is the chemical reagent that would cause calcium carbonate to release carbon dioxide. Similarly, but less obvious, hydrochloric acid is the chemical reagent that reacts with zinc to produce hydrogen even though in this case the hydrogen comes from the acid and not the metal.

To classify any of the chemicals involved in a chemical reaction as the “Reagent” is thus largely a matter of convention or perspective.

The term reagent is named after its discoverer, Victor Grignard see Grignard reagent

Reactivity–selectivity principle

In chemistry the reactivity–selectivity principle or RSP states that a more reactive chemical compound or reactive intermediate is less selective in chemical reactions. In this context selectivity represents the ratio of reaction rates.

This principle was generally accepted until the 1970s when too many exceptions started to appear. The principle is now considered obsolete ^[1].

A classic example of perceived RSP found in older organic textbooks concerns the free radical halogenation of simple alkanes. Whereas the relatively unreactive bromine reacts with 2-methylbutane predominantly to 2-bromo-2-methylbutane, the reaction with much more reactive chlorine results in a mixture of all four regioisomers.

Another example of RSP can be found in the selectivity of the reaction of certain carbocations with azides and water. The very stable triphenylmethyl carbocation derived from solvolysis of the corresponding triphenylmethylchloride reacts a 100 times faster with the azide anion than with water. When the carbocation is the very reactive tertiary adamantane carbocation (as judged from diminished rate of solvolysis) this difference is only a factor of 10.

Constant or inverse relationships are just as frequent. For example a group of 3- and 4-substituted pyridines in their reactivity quantified by their pKa show the same selectivity in their reactions with a group of alkylating reagents.

The reason for the early success of RSP was that the experiments involved very reactive intermediates with reactivities close to kinetic diffusion control and as a result the more reactive intermediate appeared to react slower with the faster substrate.

General relationships between reactivity and selectivity in chemical reactions can successfully explained by the Hammond postulate.

External links

• Reactivity–selectivity principle Gold Book Link

References

1. ↑  Minireview The Reactivity-Selectivity Principle: An Imperishable Myth in Organic Chemistry Herbert Mayr, Armin R. Ofial Angewandte Chemie International Edition Volume 45, Issue 12 , Pages 1844 - 1854 Abstract

Rare-earth mineral

A rare-earth mineral is a mineral whose principal element is a rare earth element. Yttrium is found in almost all rare earth minerals.

See also

• List of minerals

Raffinate

In solvent extraction, a raffinate is a liquid stream that remains after the extraction with the immiscible liquid to remove solutes from the original liquor. From French raffinere, to refine.

Radioisotopic labelling

Radioisotopic labeling is a technique for tracking the passage of a sample of substance through a system. The substance is “labelled” by including radionuclides in its chemical composition. When these decay, their presence can be determined by detecting the radiation they emit. Radioisotopic labelling is a special case of isotopic labeling.

For these purposes, a particularly useful type of radioactive decay is positron emission. When a positron collides with an electron, it releases two high-energy photons traveling in opposite directions. If the positron is produced within a solid object, it is likely to do this before travelling more than a millimetre. If both of these photons can be detected, the location of the decay event can be determined very precisely.

Strictly speaking, radiosotopic labelling includes only cases where radioactivity is artificially introduced by experimenters, but some natural phenomena allow similar analysis to be performed. In particular, radiometric dating uses a closely related principle.

This chemistry article is a stub. You can help Wikipedia by expanding it.

Radiochemistry

Radiochemistry deals with the use of radioactivity to study ordinary chemical reactions. All unstable isotopes elements decay and emanate some form of radiation (these are called radio isotopes).The radiation emitted can be one of three types, called alpha, beta, or gamma radiation. These three types of radiation can distinguished by their difference in penetrating power. Alpha-Can be stopped quite easily by a few centimetres if air or a piece of paper. Beta-Can be cut off by an aluminium sheet just a few millimetres thick. Gamma-This is the most penetrating and dangerous of the three, gamma radiation requires an appreciable amount of lead(Pb) to reduce its intensity.

Radiochemistry is the field of science that analyses those reactions based on radioactive emanations. Radiochemistry also includes the production of radionuclides and their compounds by processing irradiated or naturally occurring materials that have ostensible radioactive attributes.

Radiochemistry is more closely linked to nuclear chemistry, with the application of chemical techniques to nuclear studies and the application of radioactivity to the investigation of chemical and biochemical problems being a theatre of research paramount to it.

There are many natural occurring substances that contain radioactive elements in sufficient quantity, well known examples of these elements are uranium(U), radium(Ra) and thorium(Th).

This chemistry article is a stub. You can help Wikipedia by expanding it.

Q10 (temperature coefficient)

The Q₁₀ temperature coefficient is a measure of the rate of change of a biological or chemical system as a consequence of increasing the temperature by 10°C. There are many examples where the Q₁₀ is used, one being the calculation of the nerve conduction velocity and another being calculating the contraction velocity of muscle fibres. It can also be applied to chemical reactions and many other systems.

The Q₁₀ is calculated as:

where

R is the rate

T is the temperature in degrees Celsius.

Q₁₀ is a unitless quantity, as it is the factor by which a rate changes, and it a useful way to express the temperature dependence of a process.

PubChem

PubChem is a database of chemical molecules . The system is maintained by the National Center for Biotechnology Information (NCBI) which belongs to the United States National Institutes of Health (NIH). PubChem can be accessed for free through a web user interface. PubChem contains mostly small molecules with a molecular mass below 500. The American Chemical Society have tried to get the U.S. Congress to restrict the operation of PubChem, because they claim it competes with their Chemical Abstracts Service.[1].

Databases

PubChem consists of three primary databases:

• Compounds, 5.2 million entries, contains pure and characterized chemical compounds.
• Substances, 7.7 million entries, contains also mixtures, extracts, complexes and uncharacterized substances.
• BioAssay, bioactivity results from 176 high throughput screening programs with several million values.

Searching

Searching the databases is possible for a broad range of properties including chemical structure, name fragments, chemical formula, molecular weight, XLogP, and hydrogen bond donor and acceptor count.

PubChem contains an own online molecule editor with SMILES/SMARTS and InChI support that allows the import and export of all common chemical file formats to search for structures and fragments.

Each hit provides information about synonyms, chemical properties, chemical structure including SMILES and InChI strings, bioactivity, and links to structurally related compounds and other NCBI databases like PubMed.

In the text search form the database fields can be searched by adding the field name in square brackets to the search term. A numeric range is represented by two numbers separated by a colon. The search terms and field names are case-insensitive. Parentheses and the logical operators AND, OR, and NOT can be used. AND is assumed if no operator is used.

Example (Lipinski’s Rule of Five):

0:500[mw] 0:5[hbdc] 0:10[hbac] -5:5[logp]

Database fields

See also

• Chemical database
• National Center for Biotechnology Information (NCBI)
• Entrez
• PubMed
• GenBank
• Chemistry resources

External links

• PubChem homepage
• PubChem searchpage
• PubChem FAQ
• PubChem Help

Product (chemistry)

For other uses, see Product.

A product is a substance found at the end of a chemical reaction.

While the end product of some chemical reactions may be the result of a relatively rapid reaction (nanoseconds to seconds), chemical equilibria in complex systems may require years or even centuries to be established. For example, equilibria in groundwater systems with multiple components are achieved on timescales of milennia, if ever.