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Hand Boiler
A hand boiler or (less commonly) love meter is a glass sculpture used as an experimental tool to demonstrate vapour-liquid equilibrium, or as a collector's item to whimsically "measure love." It consists of a lower bulb containing a volatile liquid and a mixture of gases that is connected usually by a twisting glass tube that connects to an upper or "receiving" glass bulb. Mechanics A hand boiler functions similar to the "drinking bird" toy: The upper and lower bulbs of the device are at different temperatures, and therefore the vapor pressure in the two bulbs is different. Since the lower bulb is warmer, the vapor pressure in it is higher. The difference in vapor pressure forces the liquid from the lower bulb to the upper bulb. Thus: \Delta h = \frac where: \Delta h = the height of the column of fluid above the fluid's level in the lower bulb \Delta p = the difference in vapor pressure between the two bulbs (which can be determined via the Antoine equation) \rho = the dens ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glass Sculpture
Glass is a non-crystalline, often transparent, amorphous solid that has widespread practical, technological, and decorative use in, for example, window panes, tableware, and optics. Glass is most often formed by rapid cooling (quenching) of the molten form; some glasses such as volcanic glass are naturally occurring. The most familiar, and historically the oldest, types of manufactured glass are "silicate glasses" based on the chemical compound silica (silicon dioxide, or quartz), the primary constituent of sand. Soda–lime glass, containing around 70% silica, accounts for around 90% of manufactured glass. The term ''glass'', in popular usage, is often used to refer only to this type of material, although silica-free glasses often have desirable properties for applications in modern communications technology. Some objects, such as drinking glasses and eyeglasses, are so commonly made of silicate-based glass that they are simply called by the name of the material. Despite bei ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Condenses
Condensation is the change of the state of matter from the gas phase into the liquid phase, and is the reverse of vaporization. The word most often refers to the water cycle. It can also be defined as the change in the state of water vapor to liquid water when in contact with a liquid or solid surface or cloud condensation nuclei within the atmosphere. When the transition happens from the gaseous phase into the solid phase directly, the change is called deposition. Initiation Condensation is initiated by the formation of atomic/molecular clusters of that species within its gaseous volume—like rain drop or snow flake formation within clouds—or at the contact between such gaseous phase and a liquid or solid surface. In clouds, this can be catalyzed by water-nucleating proteins, produced by atmospheric microbes, which are capable of binding gaseous or liquid water molecules. Reversibility scenarios A few distinct reversibility scenarios emerge here with respect to the na ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Science Demonstrations
A scientific demonstration is a procedure carried out for the purposes of demonstrating scientific principles, rather than for hypothesis testing or knowledge gathering (although they may originally have been carried out for these purposes). Most scientific demonstrations are simple laboratory demonstrations intended to demonstrate physical principles, often in a surprising or entertaining way. They are carried out in schools and universities, and sometimes in public demonstrations in popular science lectures and TV programs aimed at the general public. Many scientific demonstrations are chosen for their combination of educational merit and entertainment value, which is often provided by dramatic phenomena such as explosions. Public scientific demonstrations were a common occurrence in the Age of Enlightenment, and have long been a feature of the British Royal Institution Christmas Lectures, which date back to 1825. In the television era, scientific demonstrations have featured i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemistry Education
Chemistry education (or chemical education) is the study of teaching and learning chemistry. It is one subset of STEM education or discipline-based education research (DBER). Topics in chemistry education include understanding how students learn chemistry and determining the most efficient methods to teach chemistry. There is a constant need to improve chemistry curricula and learning outcomes based on findings of chemistry education research (CER). Chemistry education can be improved by changing teaching methods and providing appropriate training to chemistry instructors, within many modes, including classroom lectures, demonstrations, and laboratory activities. Importance Chemistry education is important because the field of chemistry is fundamental to our world. The universe is subject to the laws of chemistry, while human beings depend on the orderly progress of chemical reactions within their bodies. Described as the central science, chemistry connects physical sciences wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Equilibrium Chemistry
Equilibrium chemistry is concerned with systems in chemical equilibrium. The unifying principle is that the free energy of a system at equilibrium is the minimum possible, so that the slope of the free energy with respect to the reaction coordinate is zero. This principle, applied to mixtures at equilibrium provides a definition of an equilibrium constant. Applications include acid–base, host–guest, metal–complex, solubility, partition, chromatography and redox equilibria. Thermodynamic equilibrium A chemical system is said to be in equilibrium when the quantities of the chemical entities involved do not and ''cannot'' change in time without the application of an external influence. In this sense a system in chemical equilibrium is in a stable state. The system at chemical equilibrium will be at a constant temperature, pressure or volume and a composition. It will be insulated from exchange of heat with the surroundings, that is, it is a closed system. A change of te ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Physics Education
Physics education refers to the methods currently used to teach physics. Physics Education Research refers to an area of pedagogical research that seeks to improve those methods. Historically, physics has been taught at the high school and college level primarily by the lecture method together with laboratory exercises aimed at verifying concepts taught in the lectures. These concepts are better understood when lectures are accompanied with demonstration, hand-on experiments, and questions that require students to ponder what will happen in an experiment and why. Students who participate in active learning for example with hands-on experiments learn through self-discovery. By trial and error they learn to change their preconceptions about phenomena in physics and discover the underlying concepts. Ancient Greece Aristotle wrote what is considered now as the first textbook of physics. Aristotle's ideas were taught unchanged until the Late Middle Ages, when scientists started making ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vapor–liquid Equilibrium
In thermodynamics and chemical engineering, the vapor–liquid equilibrium (VLE) describes the distribution of a chemical species between the vapor phase and a liquid phase. The concentration of a vapor in contact with its liquid, especially at equilibrium, is often expressed in terms of vapor pressure, which will be a partial pressure (a part of the total gas pressure) if any other gas(es) are present with the vapor. The equilibrium vapor pressure of a liquid is in general strongly dependent on temperature. At vapor–liquid equilibrium, a liquid with individual components in certain concentrations will have an equilibrium vapor in which the concentrations or partial pressures of the vapor components have certain values depending on all of the liquid component concentrations and the temperature. The converse is also true: if a vapor with components at certain concentrations or partial pressures is in vapor–liquid equilibrium with its liquid, then the component concentration ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gas Laws
The gas laws were developed at the end of the 18th century, when scientists began to realize that relationships between pressure, volume and temperature of a sample of gas could be obtained which would hold to approximation for all gases. Boyle's law In 1662 Robert Boyle studied the relationship between volume and pressure of a gas of fixed amount at constant temperature. He observed that volume of a given mass of a gas is inversely proportional to its pressure at a constant temperature. Boyle's law, published in 1662, states that, at constant temperature, the product of the pressure and volume of a given mass of an ideal gas in a closed system is always constant. It can be verified experimentally using a pressure gauge and a variable volume container. It can also be derived from the kinetic theory of gases: if a container, with a fixed number of molecules inside, is reduced in volume, more molecules will strike a given area of the sides of the container per unit time, causing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drinking Bird
Drinking birds, also known as insatiable birdies, dunking birds, drinky birds, water birds, dipping birds, and “Sippy Chickens” are toy heat engines that mimic the motions of a bird drinking from a water source. They are sometimes incorrectly considered examples of a perpetual motion device. Construction and materials A drinking bird consists of two glass bulbs joined by a glass tube (the bird's neck). The tube extends nearly all the way into the bottom bulb, and attaches to the top bulb but does not extend into it. The space inside the bird contains a fluid, usually colored to make the liquid more visible. The dye might fade when exposed to light, with the rate depending on the dye/color. The fluid is typically dichloromethane (DCM), also known as methylene chloride. Earlier versions contained trichlorofluoromethane. Miles V. Sullivan's 1945 patent suggested ether, alcohol, carbon tetrachloride, or chloroform. Air is removed from the apparatus during manufacture, so the spa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Charles's Law
Charles's law (also known as the law of volumes) is an experimental gas law that describes how gases tend to expand when heated. A modern statement of Charles's law is: When the pressure on a sample of a dry gas is held constant, the Kelvin temperature and the volume will be in direct proportion. This relationship of direct proportion can be written as: :V \propto T So this means: :\frac = k, \quad \text \quad V=k T where: * is the volume of the gas, * is the temperature of the gas (measured in kelvins), and * is a non-zero constant. This law describes how a gas expands as the temperature increases; conversely, a decrease in temperature will lead to a decrease in volume. For comparing the same substance under two different sets of conditions, the law can be written as: \frac=\frac The equation shows that, as absolute temperature increases, the volume of the gas also increases in proportion. History The law was named after scientist Jacques Charles, who formulated ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Benjamin Franklin
Benjamin Franklin ( April 17, 1790) was an American polymath who was active as a writer, scientist, inventor, statesman, diplomat, printer, publisher, and political philosopher. Encyclopædia Britannica, Wood, 2021 Among the leading intellectuals of his time, Franklin was one of the Founding Fathers of the United States, a drafter and signer of the United States Declaration of Independence, and the first United States Postmaster General. As a scientist, he was a major figure in the American Enlightenment and the history of physics for his studies of electricity, and for charting and naming the current still known as the Gulf Stream. As an inventor, he is known for the lightning rod, bifocals, and the Franklin stove, among others. He founded many civic organizations, including the Library Company, Philadelphia's first fire department, and the University of Pennsylvania. Isaacson, 2004, p. Franklin earned the title of "The First American" for his early and indefa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pigment
A pigment is a colored material that is completely or nearly insoluble in water. In contrast, dyes are typically soluble, at least at some stage in their use. Generally dyes are often organic compounds whereas pigments are often inorganic compounds. Pigments of prehistoric and historic value include ochre, charcoal, and lapis lazuli. Economic impact In 2006, around 7.4 million tons of inorganic, organic, and special pigments were marketed worldwide. Estimated at around US$14.86 billion in 2018 and will rise at over 4.9% CAGR from 2019 to 2026. The global demand for pigments was roughly US$20.5 billion in 2009. According to an April 2018 report by ''Bloomberg Businessweek'', the estimated value of the pigment industry globally is $30 billion. The value of titanium dioxide – used to enhance the white brightness of many products – was placed at $13.2 billion per year, while the color Ferrari red is valued at $300 million each year. Physical principles ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
