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This film is about the organic compounds we call alcohols. Alcohol is not a human invention - it occurs naturally wherever yeast spores find the right conditions to reproduce. The video shows the molecular structure of alcohols, the differences between them, explains their properties and uses and looks at their production.
The six alkaline earth metals - beryllium, magnesium, calcium, strontium, barium, and radium - rank among the most reactive elements, coming in second after alkaline metals. They don´t occur in their elemental state. This video shows the properties and reactions of alkaline earth metals in different experiments.
With a density of only around 2.7 g/cm^3, aluminium is one of the lightest metals. It is the third most abundant element in Earth's crust, is very soft, has a low melting point and excellent conductivity, making it one of the most versatile materials used in construction, packaging, and electrical engineering.
As an alternative to petroleum, the possibilities of biomass are now being explored. The film presents biomass gasification and energy generation from biomass, explains how they work and names the advantages, but also the disadvantages of the new processes, which have not been sufficiently researched for a long time.
The substances dealt with in chemistry almost never occur in pure form naturally. Even substances that we consider to be "pure" contain admixtures of other substances. Topics of this film are the different mixtures of solid, liquid and gaseous substances and their different types of heterogeneous and homogeneous mixtures.
Carbon can form multiple bonds with itself and other substances, making it one of the most versatile elements. This becomes particularly apparent in organic carbon compounds. Examples include the carbohydrate group but also petroleum, natural gas and coal, which are made up of the remains of plants and animals.
The global carbon cycle - the process by which carbon gets moved around between Earth´s atmosphere and biosphere - can be divided up into a geological and a biological carbon cycle. This video explains both of them and gives insight into the risks to Earth´s equilibrium brought on by burning fossil fuels.
Chemical equilibriums occur when reversible reactions take place in a closed system. Most chemical reactions are not only unidirectional, but are rather reversible. Chemical and dynamic equilibrium are demonstrated with various experiments. The equilibrium constant is explained and the law of mass action described.
Materials that by their mere presence can enable or speed up reactions that would either not even happen at all or take much longer to run without them are called catalysts. Catalysts are not involved in those reactions and come out untouched. They lower the activation energy and therefore speed up the reaction rate.
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 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.
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.
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.
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.
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.
Silver is considered to be the second most precious metal after gold. Silver is a brilliant white precious metal and with a density of 10.4 g/cm³, it is one of the heavy metals. Of all metals, it is the most reflective and absorbent of light. The film presents the properties of silver and how it reacts with other substances.
The simplest compounds in organic chemistry are the hydrocarbons. The film introduces the first alkanes (saturated hydrocarbons) and alkenes (unsaturated hydrocarbons) and explains their differences and properties. The substances can occur in many variants, which have correspondingly different properties.
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.
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.
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.
Synthetic fibers are made from petroleum and natural gas. This video takes a look at organic and synthetic molecule chains as well as thermoplastic and duroplastic materials, explains the difference between monomers and polymers and gives a brief overview over the history of synthetic fibers like Nylon.
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 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.
Topic of this film is the reaction of water with different substance groups, acidic and alkaline solutions. Substances that give off protons when they react with water are called acids, and substances that take up protons in a reaction with water are called bases. Gaseous acids and bases are often extremely soluble in water.
Due to its properties, the element zinc is an important working metal and in combination with other metals plays an important in metalworking. The film presents zinc´s properties and how it reacts with acids and bases. It also looks into the role of zinc in electrochemistry and in the human body´s metabolic processes.
Wasser ist der einzige Stoff, der auf der Erde natürlich in allen drei Aggregatzuständen vorkommt: flüssig, fest und gasförmig. In diesem Video geht es um die physikalischen Eigenschaften von festem Wasser - also Eis. Unter anderem geht es um die Dichteanomalie, Druckaufschmelzung und Kristallisationskerne.
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.
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.
Imagining modern life without plastics is almost impossible. We use them in construction, as food packaging, paints, or clothing. Polymerization is the reaction used in their manufacture. This video takes a closer look at how monomers are combined to form polymers and gives a brief overview over the history of plastics.
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.