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A Chemical Garden

Thomas Mann beautifully combines sensory observation and fantasy in his description of a chemical garden in the book Doctor Faustns which he wrote in his old age  [Pg.23]

1500-mL or 2000-mL beaker, watchglass to cover the beaker, safety glasses, protective gloves. [Pg.23]

The watcrglass solution is diluted with an equal amount of distilled w ater and about a liter of the resulting solution is poured into the beaker. The crystals of [Pg.23]

The waterglass solution reacts with the metal ions to form a scmipcrmcable membrane consisting of an almost insoluble precipitate of metal salts. Since the concentration of the dissolved metal salts is greater in the space between crystal and inemhiane l.lian in ilie surrounding soluiion water diffuses inio ihis space. The osmotic pressure thus increases and the membrane expands or bursts. The hole thus formed is immediately filled by the metal salt. The salt concentration is lowest at the highest point of the membrane, so that the latter normally bursts here and the plants grow upwards as in nature. [Pg.24]

On completion of the experiment the complete chemical garden is treated with dilute milk of lime, the pH being kept below 8. The mixture is then centrifuged (or simply decanted), separated from the precipitated mixture and the filtrate diluted and poured down the drain. The residue is placed in the plastic con-laiiier used lor collecting less toxic inorganic waste. [Pg.24]


A chemical garden. Vegetation created by a combination of inorganic salts... [Pg.150]

Analytical procedures can be classified in two ways first, in terms of the goal of the analysis, and second, in terms of the nature of the method used. In terms of the goal of the analysis, classification can be based on whether the analysis is qualitative or quantitative. Qualitative analysis is identification. In other words, it is an analysis carried out to determine only the identity of a pure analyte, the identity of an analyte in a matrix, or the identity of several or all components of a mixture. Stated another way, it is an analysis to determine what a material is or what the components of a mixture are. Such an analysis does not report the amount of the substance. If a chemical analysis is carried out and it is reported that there is mercury present in the water in a lake and the quantity of the mercury is not reported, then the analysis was a qualitative analysis. Quantitative analysis, on the other hand, is the analysis of a material for how much of one or more components is present. Such an analysis is undertaken when the identity of the components is already known and when it is important to also know the quantities of these components. It is the determination of the quantities of one or more components present per some quantity of the matrix. For example, the analysis of the soil in your garden that reports the potassium level as 342 parts per million (ppm) would be classified as a quantitative analysis. The major emphasis of this text is on quantitative analysis, although some qualitative applications will be discussed for some techniques. See Workplace Scene 1.1. [Pg.3]

From recent work, we do know that chemical signals from the seeds direct the ants selections. Although the story is still incomplete, an extraordinary finding has been that a chemical compound called MMS (methyl 6-methylsalicylate) is present in the seeds the ants choose. MMS is found in the seeds of the ten or twelve unconnected species from seven plant families that flourish in Peruvian ant gardens. The ants seem to find this compound irresistible. Offered inert particles coated with MMS, they become excited, pick up these decoy seeds, and occasionally carry them about. [Pg.41]

Alkaloids from many plants are considered to be used as biological fertilizers in ecological cultivation. This is very important especially in cases when more attention is given to these plants, which play not only a role in production but also in the cyclical maintenance of a field, garden or forest ecosystems . Plants containing alkaloids, for example lupines, have the ability to establish complexes with the soil and with the rhizosphere. The excretion of many chemicals from roots to soil occurs in this complex. Plant mediation with the soil environment is the result. The alkaloids play a major role in this plant-soil interaction system. [Pg.194]

A successful garden represents a broad spectrum of chemical processes. Photosynthesis provides the route by which diverse chemical transformations use sunlight, water, carbon dioxide, and inorganic chemical elements to produce life-sustaining organic molecules and oxygen (Equation 1). This solar-powered rearrangement of matter is the foundation of almost all ecosystems and is an important example of how chemistry applies to the study of life. [Pg.133]

A healthy garden represents a chemical laboratory in which a host of chemical processes are occurring in synchrony with our natural world. When the gardener has chosen adapted crop varieties, and has managed both soil and crops wisely, these chemical processes unfold in such a way that the garden harvests the sun s energy efficiently, and converts a portion into useful products, see also Agricultural Chemistry Herbicides Insecticides Pesticides. [Pg.139]

Humankind has continually developed and progressed over the centuries, and nowhere is this more evident than in recent modem history. The past few decades have demonstrated man s dependency on chemical and pharmaceutical products to achieve both material benefit and health. Indeed, the assimilation of chemicals into our daily activities (e.g., cleaning, washing, gardening, preparing of food and beverages) and maintenance has become commonplace. One may even state that today we are a chemical society ... [Pg.1]

Although substituting a mycoherbicide for a chemical herbicide seems to be a relatively recent innovation, ny modern pest controls began in Socrates garden. Smith and Secoy, researchers with Ag Canada, reported on several writings from the ancient Mediterranean period (25). ... [Pg.244]

Quite at the beginning of this chapter I mentioned "different kinds of plant taxonomists engaged in different kinds of research". I hope that indeed it became clear that under the roof of plant systematise there is a large diversity of activities and purposes. One may find a plant taxonomist at work behind a chemical apparatus, between piles of herbarium specimens, in a garden between flowers encased in gauze, in a cold culture room between bottles with seaweeds, in a tropical forest, as well as behind a scanning electron microscope or a computer. [Pg.13]

The reasons for the formation of the "hot" (>150°C) seams is not clear. Conjecture is that the biological exotherm from decomposition (composting) caused a chemical exotherm, perhaps from an oxidant in the pellets. The d-RDF was made from household waste and some few portions may have contained an oxidant, such as nitrates in garden fertilizer. [Pg.141]

Biological units (BU) do not exist in isolation. There are relations with a physical environment, with a chemical environment, and with other BU. These other BU may be at the same hierarchical level as the target BU, as between a vegetable plant and a weed in a garden, or as between two hepatic cells in the liver. They may also be at different hierarchical levels, as with an ape in a forest... [Pg.283]


See other pages where A Chemical Garden is mentioned: [Pg.23]    [Pg.355]    [Pg.241]    [Pg.241]    [Pg.441]    [Pg.23]    [Pg.355]    [Pg.241]    [Pg.241]    [Pg.441]    [Pg.38]    [Pg.52]    [Pg.179]    [Pg.94]    [Pg.93]    [Pg.46]    [Pg.14]    [Pg.88]    [Pg.82]    [Pg.90]    [Pg.3]    [Pg.15]    [Pg.236]    [Pg.138]    [Pg.192]    [Pg.65]    [Pg.1]    [Pg.213]    [Pg.7]    [Pg.21]    [Pg.3]    [Pg.276]    [Pg.422]    [Pg.634]    [Pg.193]    [Pg.182]    [Pg.499]    [Pg.214]    [Pg.37]    [Pg.13]   


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