Household chemistry

Understanding Chemical Reactivity Accidents. Household Chemistry Use and Misuse. 

Silicone polyethers are important nonionic surfactants that are also used in cosmetics and household chemistry. However, their most important application is the manufacture of polyurethane foams, both rigid and flexible ones. There are no substitutes for them and their role eonsists in the facilitation of mixing of foam components. They prevent from the formation of large bubbles, facilitate the control of fluidity of liquid mixture (that expands due to the bubble growth), and they enable accurate control of time and degree of foam opening. 

It would be difficult to over-estimate the extent to which the BET method has contributed to the development of those branches of physical chemistry such as heterogeneous catalysis, adsorption or particle size estimation, which involve finely divided or porous solids in all of these fields the BET surface area is a household phrase. But it is perhaps the very breadth of its scope which has led to a somewhat uncritical application of the method as a kind of infallible yardstick, and to a lack of appreciation of the nature of its basic assumptions or of the circumstances under which it may, or may not, be expected to yield a reliable result. This is particularly true of those solids which contain very fine pores and give rise to Langmuir-type isotherms, for the BET procedure may then give quite erroneous values for the surface area. If the pores are rather larger—tens to hundreds of Angstroms in width—the pore size distribution may be calculated from the adsorption isotherm of a vapour with the aid of the Kelvin equation, and within recent years a number of detailed procedures for carrying out the calculation have been put forward but all too often the limitations on the validity of the results, and the difficulty of interpretation in terms of the actual solid, tend to be insufficiently stressed or even entirely overlooked. And in the time-honoured method for the estimation of surface area from measurements of adsorption from solution, the complications introduced by... 

By this time, Muller had a wife and children. His wife, Friedel Riiegseg-ger, took charge of the household and raised their two sons and daughter so that Paul could concentrate on chemistry. Together, Paul and Friedel... 

Both ammonia and bleach are useful household products for cleaning stains, sanitizing surfaces, disinfecting, and deodorizing. However, the chemistry of these individual products dictates that you always heed the warning Caution Never mix bleach and ammonia cleansers ... 

Several articles in the area of microwave-assisted parallel synthesis have described irradiation of 96-well filter-bottom polypropylene plates in conventional household microwave ovens for high-throughput synthesis. While some authors have not reported any difficulties in relation to the use of such equipment (see Scheme 4.24) [77], others have experienced problems in connection with the thermal instability of the polypropylene material itself [89], and with respect to the creation of temperature gradients between individual wells upon microwave heating [89, 90]. Figure 4.5 shows the temperature gradients after irradiation of a conventional 96-well plate for 1 min in a domestic microwave oven. For the particular chemistry involved (Scheme 7.45), the 20 °C difference between the inner and outer wells was, however, not critical. 

The chemical industry is actually a set of related industries with many diverse functions and products. Certain raw materials are used to prepare key chemicals, monomers, and intermediates that may be sold independently or used directly in additional steps to give various polymers and end chemicals. These in turn can be formulated and fabricated into chemical products, which can sometimes be modified into finished products. There is a flow of materials and products from raw sources to finished formulations. Although the division is approximate, about 60% of the chemical industry manufactures industrial products that are further modified, whereas 40% of their products are sold directly to the consumer. Chemistry may not be a household word, but it should be. Actually, the older name for the Chemical Manufacturing sector is Chemicals and Allied Products, still used sometimes and a term that adequately describes the breadth of the industry. 

In 1903 M. and Mme. Curie, together with M. A.-H. Becquerel, were awarded the Nobel Prize in chemistry. The Curie household with its two bright little daughters was a most happy one, and the gifted parents looked forward to a lifetime of united efforts for science. That dream was not to be fulfilled. On April 19, 1906, as Pierre Curie was crossing a busy street in Paris, he was struck by a heavy vehicle and instantly killed (61). 

Because chemistry is such a broad field, it is difficult to give a concise job description of a chemist. In general, chemists study the composition, structure, and characteristics of matter in an attempt to improve substances and products discover new substances and products and improve and develop chemical processes. Chemists work in a multitude of industries including agriculture, medicine, pharmaceuticals, textiles, petrochemicals, mining, plastics, hazardous materials, electronics, adhesives, paints, household products, and cosmetics. 

Sulfur chemistry is important both in combustion and in the petrochemical industry. Most fossil fuels contain sulfur, and also biofuels and household waste have a sulfur content. As a consequence sulfur species are often present in combustion processes. Knowledge of gas-phase sulfur chemistry occurring in combustion has bearing on pollutant emissions and on system corrosion. Air pollution by SO2 still constitutes a major environmental concern and search for control techniques has motivated research also on high-temperature homogeneous sulfur chemistry. However, more recent work on sulfur chemistry has been concerned mainly with the effect of sulfur on other pollutant emissions, such as NO and CO, and with the SO3/SO2 ratio, which is important for the corrosive potential of the flue gas and for formation of sulfur containing aerosols. 

Hands-On Chemistry activities that allow students to experience chemistry outside a formal laboratory setting. These activities can be performed using common household ingredients and equipment. Most chapters have two or three Hands-On features, which lend themselves well to distance learning or to in-class activities. 

In the literature, first microwave-assisted experiments on organic synthesis employed multimode household microwave ovens [12,13]. More recently, the use of microwave reactors for chemical syntheses has become more advanced, and, at the moment, some chemical journals specializing in organic chemistry intend to refuse manuscripts in which experiments were carried out in a domestic microwave oven (even including ovens with... 

Indoor Chemistry Various terpenes and terpenoids are emitted from household products and building materials. Ozone that has entered from outdoors or has been generated indoors can react with these compounds, either in the gas phase or on the surface of materials. The resulting oxidation products will contribute to the production and growth of meaningful quantities of secondary organic aerosols (SOA). The formation and growth of SOA can be studied under controlled conditions in test chambers (see also Chapter 13). 

Compared with oil (and especially coal), natural gas as an energy carrier and raw material has several important advantages reduced environmental pollution in industry, households, and energy production, where coal has been extensively replaced by gas. There are also wide possibilities for gas to be used in chemistry. In the U.S.A. and many other countries, natural gas has become the prevalent energy... 

Chemistry is taught at various levels at the universities. Nurses are exposed to various anesthetics. Hair dressers, dry cleaners, farmers are working with numerous chemicals. Housewives are using a wide range of chemicals for household cleaning, for painting the house, etc. It is difficult to think about a profession which does not require, at one time or another, at least some exposure to chemicals. 

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