Marktplatz für digitale Bildungsmedien
Kalkstein wird unter Tage abgebaut. Im Film wird gezeigt, wie er für die Weiterverarbeitung auf 1000 °C erhitzt wird und zu ätzendem Kalziumoxid reagiert. Mit Wasser wird er zu Löschkalk, mit Sand zu Mörtel. Nach der Verwendung verdunstet das Wasser, und aus dem Löschkalk wird wieder harter Kalkstein.
Kristalle kommen überall vor. Der Film erklärt, wie sie in der Natur durch geologische Prozesse über Jahrmillionen natürlich wachsen und im Labor schneller hergestellt werden können: Nicht mehr lösbares Salz aus übersättigten Lösungen kristallisiert aus. Auch das Gesetz der Winkelkonstanz wird erklärt.
Zwei Sequenzen geben einen Überblick über Basen und Laugen im Alltag. Eigenschaften von Basen werden demonstriert. Laborversuche zu Natrium- und Kaliumhydroxid und Kochsalzelektrolyse, Animationen zu Elektrodenvorgängen und Anwendungsbeispiele aus der Großtechnik runden das Medium ab.
Umkehrbare chemische Reaktionen können in geschlossenen Systemen gleichzeitig ablaufen. Der Film zeigt dies anhand von erhitztem Ammoniumchlorid bzw. Ammoniak und Chlorwasserstoff. Es wird erläutert, wie ein chemisches Gleichgewicht dabei zustande kommt und dass es sich nicht um ein statisches handelt.
Um Metalle zu gewinnen, müssen Redoxreaktionen durchgeführt werden. Der Film zeigt die Reaktivität der unterschiedlichen Metalle und gibt Beispiele mit der Gewinnung von Kupfer, Aluminium und Zink. Mit Formeln, Animationen, Filmaufnahmen, Bildern und Grafiken wird der Vorgang verdeutlicht.
Man kennt die Nummern mit dem "E" davor - Zusatzstoffe in Lebensmitteln. Doch was bedeuten sie? Der Film gibt einen Überblick über die wichtigsten Zusatzstoffe und regt dazu an, kritisch auf die Zutatenliste zu schauen, bevor man sich für ein Produkt entscheidet.
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.
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.
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.
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.
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.
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.
Iron occurs naturally as mineral iron core. Before it can be used in the industry, it must first be processed into iron or steel. The film explains how blast furnaces are constructed and what chemical processes take place inside them before steel or alloys are finally produced with the addition of other metals.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
It is the most abundant element on Earth and almost all living beings need it - oxygen. Under normal conditions, it is a colourless and odourless gas, occurring as a two-atom molecule. This video explains oxygen´s properties, shows its position in the periodic table, and demonstrates its high reactivity in several experiments.
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.
Viele Alltagsgegenstände bestehen aus Kunststoffen oder "Polymeren". Die drei häufigsten Kunststoffe Polyethylen, Polypropylen und Polyvinylchlorid werden auf diesem Medium vorgestellt. Eigenschaften verschiedener Polymere werden erklärt und ihre Molekülstrukturen in anschaulichen Animationen gezeigt.
The particle model helps us get an idea of the structure and properties of substances. Sugar, for instance, can appear as rock candy, granulated sugar or icing, and can even be fully dissolved in water - all without a change to its particles. This film visualizes the particle model using different experiments.
Copper is one of the metals humans have been using the longest. In nature, it can be found in its pure form as nuggets, and humans began using it 10,000 years ago. Copper can be worked easily when smelted and cast. Using various experiments, this film demonstrates copper´s properties and its reactions with other substances.
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.
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.