In this experiment the  composition of air is investigated. Therefor soild copper is heated on air. Copper combines with the oxygen of air and forms copper oxide. If this reaction is performed in a closed apparatus and the air volume is measured before and after the experiment, the difference of the measured volume shows the oxygen content of the air.

Learning objectives

• Composition of air
• Oxidation reaction

This student experiment is investigating how and why a candle burns. This experiment explains clearly which processes occur during burning a candle. Many students know that wax is a relatively soft and malleable material (often consists of stearin or paraffin). But perhaps they are not aware that in a candle flame the wax does not burn, but from the liquid wax riseses  gases (above the wick) which burn. This observation can also be applied to other materials,  it is the rising vapours that burn, not the substances themselves.

Learning objectives

• Combustion reaction
• Candle flame

Benefits

• Easy teaching and efficient learning by using interactive experimentation IMPACT-Software
• Experiment is part of a complete solution set with experiments for all Inorganic Chemistry matched with international curriculum: all topics are covered

The Bunsen burner is based on the principle of adjustable gas combustion with air supply. By varying the quantity of air supplied, different burner temperatures can be achieved. Students investigate in this experiment the construction and mode of operation of a Bunsen burner.

Learning objectives

•  Principle of an Bunsen burner

Benefits

• Easy teaching and efficient learning by using interactive experimentation IMPACT-Software
• Experiment is part of a complete solution set with experiments for all Inorganic Chemistry matched with international curriculum: all topics are covered

Air (oxygen) is needed for many reactions, e.g. for combustions.  In  this  experiment students determine whether air as a whole is required for combustion. This experiment shows that in combustion reactions only a part of the air is consumed. This result means that air must be a mixture of substances.

Learning objectives

• Air is a mixture of substances
• Only a part of the air promotes combustion reactions

Benefits

• Easy teaching and efficient learning by using interactive experimentation IMPACT-Software
• Experiment is part of a complete solution set with experiments for all Inorganic Chemistry matched with international curriculum: all topics are covered

The combustion of compounds is also a chemical reaction with (components of) air. In this experiment students determine the importance of air for combustion processes and learn that the presence of air is required for combustion. It is demonstrated that even very highly flammable substances such as methylated spirits burn only in the presence of air.

Learning objectives

•  Air is required for combustion reaction
• Combustion reaction

Benefits

• Easy teaching and efficient learning by using interactive experimentation IMPACT-Software
• Experiment is part of a complete solution set with experiments for all Inorganic Chemistry matched with international curriculum: all topics are covered

Perfect for student experiments.

Function and Applications
Cobra SMARTsense is the ideal solution for inexpensive digitalization of science teaching. The sensors connect wirelessly (Bluetooth) or wired (USB) directly to the student’s digital end device (smartphone, tablet or desktop PC). Using the free and award-winning measureAPP measurement software for iOS, Android and Windows, measured values can be easily recorded and graphically displayed. If more evaluations are needed, the measureLAB measurement software for Windows and macOS can be used.

With the sensor, single drops can be counted and directly converted into a volume. If you connect a pH electrode, a titration can be carried out easily and precisely.

Benefits

• Simplicity – Get started right away with the Bluetooth-enabled end device and the free measureAPP
• Completeness – Over 40 sensors with more than 70 measured quantities for all subjects
• Endurance – Intelligent and efficient power management for up to 50 hours on one battery charge
• Variety – The free measureAPP provides perfect support and runs on all mobile platforms and end devices. For professionals, measureLAB is available.
• Performance – Up to 32,000 measured values per second guarantee precision and recordings with up to 17 measuring channels simulaneously are possible.
• Connectivity – Fast connection of sensors and data exchange via Bluetooth – for many sensors additionally possible via USB.

Equipment and Technical Data

• Dropcounter:
  • Range: 0 … ∞
  • Resolution:30 Imp/s
• pH:
  • Range: 0 … 14
  • Resolution: 0.01
• Samplerate: 50 Hz

The PH-Elektrode is sold seperately.

The sensor contains a USB-C rechargeable lithium polymer battery.

Different salts can be caused to react with each other while at the same time an exchange of cations or anions takes place.If during this process a salt precipitates out in the form  of an insoluble component, this can be taken as a test reaction.

Tasks

Prepare several salt solutions and study the processes taking place when the solutions are mixed.

Benefits

• Easy teaching and efficient learning by using interactive experimentation IMPACT-Software
• Experiment is part of a complete solution set with experiments for the topic acids, alkalis and salts matched with international curriculum: all topics are covered

Carboxylic acids are potential electrolytes which exist in a weakly dissociated condition in aqueous solutions. The location of the dissociation equilibrium is quantitatively described by the Ka or pKa value which can be determined with potentiometric measurements.

Benefits

• Simplified implementation: all pre-settings already prepared
• Drop counter optimizes the experimental procedure

Tasks

1. Measure the alteration of the pH value during a titration of approximately 0.1 molar aqueous solutions of formic acid, acetic acid, monochloroacetic acid, propionic acid, butyric acid and lactic acid with a 0.1 molar sodium hydroxide solution at constant temperature using Cobra SMARTsense-system.
2. From the neutralisation curves read the pKa values of the acids and compare them.

Learning objectives

• True and potential electrolytes
• Strong and weak acids
• Law of mass action
• Henderson-Hasselbalch equation
• Dissociation constant and pKa value
• Substituent effects
• Potentiometry

Necessary accessories

• Precision balance 620g/0.001g

Software included. Computer not provided.

Approaching a very sharp metal tip to an electrically conductive sample by applying a electrical field leads to a current between tip and sample without any mechanical contact. This so-called tunneling current is used to investigate the electronic topography on the sub nanometer scale of a fresh prepared graphite (HOPG) surface. By scanning the tip line by line across the surface graphite atoms and the hexagonal structure are imaged.

Benefits

• Observe atoms within minutes
• Custom-designed for use in teaching labs
• Microscope consists of one compact, portable instrument, no additional instruments required
• Vibration-isolated for better and reproducible results
• Can be used both for imaging of atomic resolution and for spectroscopy
• Additional experiment with gold sample can be performed
• With interactive teaching and learning software

Tasks

1. Prepare a Pt-Ir tip and the graphite (HOPG) sample and approach the tip to the sample.
2. Investigate the topography of clean terraces and the step height between neighboring terraces in constant-current mode.
3. Image the arrangement of graphite atoms on a clean terrace by optimizing tunneling and scanning parameters. Interpret  the structure by analyzing angles and distances between atoms and atomic rows and by using the 2D and 3D graphite model.
4. Measure and compare images in the constant-height and constant-current modes.

Learning objectives

• Tunneling effect
• Hexagonal structures
• Scanning Tunneling Microscopy (STM)
• Imaging on the sub nanometer scale
• Piezo-electric devices
• Local Density Of States (LDOS)
• Constant-Height-Mode
• Constant-Current-Mode

Software included. Computer not provided.

40 selected raw materials for producing metals; particularly rich-content ores have been selected as display pieces. The corresponding description contains details of the most important ore deposits worldwide. They give additional information about their use and origin, as well as the special position of the ores within the minerals.

The set contains the following ores:

• Aluminum Ore: Bauxite
• Magnesium ores: Manesit, Dolomite
• Beryllium Ore: Beryl
• CE-ore: Bastnaesite
• Uranium-ore: Carnotite
• Calcium-ore: Calcite
• Strontium ore: Strontianite
• Barium ore: Barite
• Lithium Ore: Amblygonite
• Sodium-ore: Halit
• Potassium ore: Sylvite
• Rudidium, cesium ore: Carnallite
• Boron ore: Ulexite
• Iron ore: Mangetit, Hematite
• Manganese ore: Limonite, Siderite, Pyrolusite, Mangannomelan
• Nickel ore: Nickeline
• Cobalt ore: Skutterudite
• Chrome Ore: Dhromite
• Vanadium Ore: Descloizite
• Titanium ore: Zemenit
• Molybdenum ore: Molybdenite
• Tungsten ores: Wolframite, Scheelite
• Zirconium ore: Zircon
• Copper Ores: Chalcocite, Chalcopyrite
• Lead Ores: Bornite, Tetrahedrite
• Zinc Ore: Galanit
• Tin-ore: Sphalerite, Smithsonite
• Mercury-ore: Cassiterite
• Antimony ore: Cinnabar
• Silicon ores: Stibnite, Quartz

Equipment and technical data

• Set of 40 pieces
• Format of the pieces 45×60 mm, in a wooden box with lid
• Dimensions 260×495 mm