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A science experiment on water molecules is presented. A list of materials is provided, along with preparation and safety considerations, specific procedures, and discussion topics. It is concluded that cohesive force is the attractive force of like molecules for each other and keeps them together until the molecules meet another material.

What! will the line stretch out to the crack of doom? When Lewis Carroll's Walrus suggested that the time had come ‘to talk of many things; of shoes and ships and sealing wax, of cabbages and kings’, the intention was to reel off an impressively incongruous list of items. In point of fact, however, he was merely reciting an inventory of materials all of which are at least partly composed of polymers. And the list was by no means exhaustive, for he could have gone on to add paper and paint, rubber and rope, fur and flax, and wood and wool, and so on. The polymer domain is a veritable pot-pourri which displays greater variety than is seen in any other class of substances. Of all materials used by Man, those based on polymer molecules have been around longest. Wood, for example, was pressed into service long before metals were being smelted, and wood is composed of cellulose, lignin and resins, all of which are natural organic polymers. Nevertheless, an adequate knowledge of polymer structure and properties has been acquired only during recent decades. The reason for the delay lies in the fact that these molecules are frequently very large and complex compared with anything encountered in metals and ceramics. Analysis of such huge aggregates of atoms, with molecular weights frequently running into the hundreds of thousands, has required the sophistication of modern instrumentation, and polymer science is still a relatively young discipline. [ABSTRACT FROM AUTHOR]

All things began in order, so shall they end, and so shall they begin again; according to the ordainer of order and mystical mathematics of the city of heaven. Until now, our discussion has concerned isolated atoms and clusters of very few atoms. Considering that a single cubic centimetre of a typical piece of condensed matter, a block of stainless steel for example, contains approximately 1023 atoms, we see that there is still a long way to go in the description of actual substances. We must now inquire how large numbers of atoms are arranged with respect to one another, so as to produce the great variety of known materials. It will transpire that the observed arrangements are dictated both by the forces between atoms and the prevailing physical conditions. Before going into such details, however, it will be useful to examine the simple geometrical aspects of the question. It is frequently adequate to regard atoms as being spherical. The two-dimensional equivalent of a sphere is a circle, so we can begin by considering the arrangement of circles on a piece of paper. The circles could be drawn at random positions, well spread out and with close encounters occurring only by occasional chance. This is a reasonable representation of the instantaneous situation in a simple monatomic gas. A variant of this drawing would replace the single circles by small groups of circles, and we would then have a molecular gas. [ABSTRACT FROM AUTHOR]

Chapter 4 of the book "Stop Faking It! Finally Understanding Science So You Can Teach It" is presented. It discusses the polar nature of some liquid molecules leads to adhesion, which is being described as the attraction of liquid for a different substance. It explores the change in speed of fluids which is governed by a given equation that applies to liquids than to gases.

A science experiment to measure surface tension of liquids is presented. A list of materials is provided, along with preparation and safety considerations, specific procedures, and discussion topics. It is concluded that water molecules squeeze together, forming a dense layer called surface tension when they contact air or other matter.

'tis, we musicians know, the C Major of this life. Paintings and museum reconstructions depicting the activities of medieval alchemists can easily give the wrong impression of the chemical knowledge of that period. Inanimate objects such as crystals are seen sharing shelves with the preserved bodies of small creatures, a common feature of the early laboratory. This could be taken to suggest that the scientists of those days had grasped the unity of chemistry: that in spite of great differences in their external appearance, Nature makes no distinction between chemical combinations in living and dead substances. Nothing could be farther from the truth. The universally held belief was that the matter contained in living organisms possessed an essential extra ingredient, a vital force, the mysterious origin of which was attributable to divine powers. This attitude was epitomized in the succinct classification to be found in the book Cours de Chyme, published by Nicholas Lemery in 1685. His division is still to be found in the standard first question of a popular parlour game: ‘animal, vegetable or mineral?’. By the end of the eighteenth century, the vital force theory was in rapid decline. Antoine Lavoisier, analyzing typical organic compounds, found them to contain inorganic substances such as hydrogen, oxygen, nitrogen, carbon, sulphur and phosphorus. The basic principles that govern chemical change, such as conservation of total mass, were being established during this period, and in 1844 Jöns Berzelius showed that they apply to all matter irrespective of whether it is inorganic or organic. [ABSTRACT FROM AUTHOR]

Chapter 5 of the book "Stop Faking It! Finally Understanding Science So You Can Teach It" is presented. It discusses the change in state of a substance, which is being described as a transfer of energy in the form of heat. It highlights the indication of temperature changes of a substance that can affect the speed of its molecules. It also explores the study of relative humidity and its computation on getting its amount.

A review is given of the gasification of carbonaceous materials by oxygen containing reactant molecules, with an emphasis on the attempt to unify the mechanistic description of the gasification process. This seems to hold for both the uncatalysed and the alkali-catalysed reaction at elevated temperatures, although clear exceptions exist. Especially transient kinetic experiments, employing labelled molecules, and the application of molecular orbital calculations hold promise for the further elucidation and description of reaction models. [ABSTRACT FROM AUTHOR]

Describes the parallelization of molecular mechanics program based on a sequential Formula Translation programming language to run on novel hardware. Methods in optimizing the structure of a molecule; Details on the energy minimization procedure; Overview of the parallel energy minimization algorithm.