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This film is about the technical limestone cycle. Limestone is mined and processed industrially. Carbon dioxide bound in limestone is dissolved and forms calcium oxide. When water is added, calcium carbonate forms in an exothermal reaction. It reacts with carbon dioxide in the air, forming calcium carbonate again.
The natural limestone cycle: Carbonated water flows over limestone, the calcium carbonate reacts with the carbonic acid and forms calcium hydrogen carbonate. When this water evaporites, the mixture of dissolved carbon dioxide, carbonic acid and calcium hydrogen carbonate turns back into calcium carbonate and carbon dioxide.
White deposits on water taps and scale in kettles are the result of hard water. Water hardness is a measure of the concentration of calcium and magnesium ions in water.
This film shows how water hardness is measured and which consequences the hardness of water has. Also methods for softening water are shown.
This video takes a closer look at iodine, an element in the halogen family. At room temperature, iodine has a metallic sheen and sublimes to a purple vapour as soon as it is just lightly heated up, earning it its name ("ioiedis" means "violet" in Greek). Iodine is essential for making thyroid hormones.
Die Oberfläche der Erde ist zu rund zwei Dritteln von Wasser bedeckt. Kein anderer Stoff kommt natürlich auf der Erde flüssig, fest und gasförmig vor. In diesem Video geht es um die physikalischen Eigenschaften von flüssigem Wasser. Beleuchtet werden unter anderem die Kohäsion, sowie der Siedepunkt und der Gefrierpunkt von Wasser.
Wasser ist der einzige Stoff, der auf der Erde natürlich in allen drei Aggregatzuständen vorkommt. In diesem Video geht es um die physikalischen Eigenschaften von gasförmigem Wasser. Neben der Verdampfung und dem Sieden behandelt der Film auch Verdunstung, Kondensation und den sogenannten Sättigungsdampfdruck.
The film gives an overview of the material properties of thermal and electrical conductivity. Examples and experiments are used to explain how well heat and electricity are passed on through various solid and liquid substances. In this context, the video explains the concept of electrical resistance.
To find out whether a liquid is acidic or alkaline, indicators are used to measure pH levels. The pH scale ranges from 0 (extremely acidic) to 14 (extremely alkaline). Pure water sits in the middle of the scale with a pH of 7. Using various experiments, this film shows how to measure the pH levels of aqueous solutions.
Nitrogen from the Earth´s atmosphere is converted by bacteria and then processed by plants. Humans and animals ingest these nitrogen compounds in their food. The nitrogen is returned to the soil in animal excrement that contains urea and in rotting plants. This film shows the nitrogen cycle and the Haber-Bosch process.
The atmospheric greenhouse effect - a warming of the Earth´s surface by heat trapped by the sun - is what made our planet habitable in the first place. This video explains in detail how this effect works and identifies the differences between the natural and the threatening man-made greenhouse effect.
For a fire to occur, three conditions must be met: There must be combustible material, enough oxygen, and a sufficiently high initial temperature to provide the necessary activation energy. The video shows how firefighters deal with this so-called "burning triangle" and gives an overview over the best extinguishing methods.
Topics of this film are fats and fatty oils. Chemists call them lipids, and they are a key component of our diet. If the substance is solid or semi-solid at room temperature we call it fat, if it is fluid we call it oil. Its correct technical name is "fatty oil" because - from a chemical point of view - there are other oils.
Exothermic chemical reactions give off more energy than they themselves need for their process. The film explains combustion, which is the most important exothermic reaction - we use it to produce heat for example. It is the most commonly used chemical reaction, and it is also the oldest one known to mankind.
Endothermic reactions consume more energy than they release, whereas the opposite is true for exothermic reactions. Therefore, there are many applications for the latter. The film presents various forms of exothermic reaction and shows how, for example, combustion, thermite reactions and explosions can be used beneficially.
Electroplating, colloquially known as galvanising, is the electrochemical deposition of metal layers on so-called substrates - for example, coating a piece of metal with a usually very thin layer of a more noble metal. The process is named after the man who discovered it, the Italian doctor Luigi Galvani.
With fossil fuels dwindling, finding alternatives to them becomes increasingly important. One way to meet our energy needs without oil and gas is solar power. This film explains how sunlight can be converted into useable energy, what problems there still are with solar power, and takes looks at the history of its discovery.
We see crystals everywhere in nature. They fascinate us with their shape and repetition - but how are they formed? This video looks at the various types of crystals, shows their formation in experiments and explains important terms and concepts such as the crystal lattice, quasi crystals and the law of constant angles.
In neutralization reactions, the pH values of acids and bases cancel each other out. The film shows this using the reaction of hydrochloric acid and caustic soda as an example. The products are described, the titration procedure and the use of neutralization reactions in everyday life are demonstrated.
Oxidation is a chemical reaction. It runs when a candle is burning or a rocket is launched. An old rusted iron fence is actually the result of oxidation. And oxidation reactions even take place in our bodies. In this video, the characteristics of chemical reactions are explained and illustrated through different examples.
Each element has a name. The subject of this film is how the naming is done. The names consist of the names of the elements in combination with a multiplication affix and a suffix. This film explains the nomenclature (i.e., the naming system) of inorganic compounds in an entertaining and step-by-step manner.
A water molecule, one of the most important solvents, is made up of two hydrogen and one oxygen atom. Due to the position of the atoms, the electrical charge in the molecule is asymmetrical. The hydrogen molecule has an electrical plus and negative pole. The film shows what water´s property as a solvent is all about.
We encounter sodium in various forms in many places in everyday life, including the kitchen. The film introduces sodium and sodium hydroxide, points out their differences, and demonstrates their material properties by means of experiments. The very different uses of the reactive element are also shown.
This film is about the separation methods that can be used to split mixtures into their different components. It explains the separation methods decantation, sedimentation, sink-float separation, centrifugation, picking, filtration, evaporation, distillation, adsorption, extraction, chromatography, and combinations thereof.
There are different groups of substances to which substances are assigned according to their characteristic properties. The film shows what these properties are, namely the state of aggregation, the melting or boiling temperature, metallic sheen, hardness, density, solubility and finally conductivity.
Sulfur was already used 5000 years before Christ to bleach textiles and as a disinfectant. As one of the most reactive elements, sulfur consists of atoms arranged in a ring. The video introduces the different forms of sulfur and shows in several experiments how it behaves and reacts with other elements.
For a long time, it was considered certain that organic substances could not be produced from inorganic ones. The mixture of potassium cyanate and ammonium sulphate, which produces organic urea, disproved this thesis. The film shows the experiment including the proof and explains the many uses of urea.
Titration is used for the exact measurement of amounts and is a part of quantitative analytical chemistry. The most important instrument in titration is the burette, a glass tube with a scale. With its help, the concentration of a sample solution can be determined by adding a precise amount of a known standard solution.
A redox reaction happens when oxidation and reduction take place simultaneously. Redox reactions are necessary to extract metals like iron or copper. This video explains what oxidizing agents and reducing agents are, why some metals don´t easily react with oxygen, and uses experiments to demonstrate redox reactions.
Chemical reactions take different forms: It pops or bubbles, but sometimes a reaction is barely visible. The film shows the common features of chemical reactions: Starting material and product, exothermic and endothermic reactions as well as the most important influencing variables of chemical reactions.
Metals that quickly release electrons, electron donors, are called non-precious. Electron acceptors, i.e., metals that release only very few or no electrons at all, are precious. Metals can be put into an order, the electrochemical series, according to the readiness with which they release electrons.