Microschaalexperimenten

Information on Microscale Experiments in the Netherlands
Nederlandse versie van deze pagina

  • Chemistry lab more important than ever
  • Student labs
  • Microscale experiments
  • From macro to micro
  • The glassware
  • The teaching material
  • Project membership
  • Costs
  • Summary of Advantages
  • Need More information?

    • Chemistry lab more important than ever

    In the new so-called Second Phase of secondary education, an increased importance is placed on practical skills and independence of the students. In Chemistry, for example, students will need to prepare a final examination file which includes their lab work, practical tasks as well as a profile paper including independent research.

    Student labs

    Changing demonstration experiments into student labs can help develop practical skills and teach students independence. However, few teachers will let their students carry out organic chemistry experiments independently. Often, the risks are considered too high, the experiments will take longer than the class time permits, or there is a shortage of lab glassware. As a result, this part of chemistry, while so important to society, remains out of the reach of students. As a consequence, final exams are limited to the analysis of aqueous solutions

    Microscale experiments

    Worldwide, a so-called microscale movement is taking place. The idea is simple: convert existing experiments to microscale and save on chemicals. This will save costs, it will be safer for the students and it will cause much less waste. Moreover, processes will take place much faster so that even the slower organic syntheses will become available as student experiments. Demonstration experiments can become student lab experiments without causing an increase in the amount of chemicals used.

    These microscale experiments are becoming increasingly popular in the student labs. Teachers are developing their own microscale experiments and manufacturers are introducing new microscale glassware.

    From macro to micro

    In a joint effort, the University of Amsterdam and the Chemistry Communication Center Foundation (C3 Foundation) are introducing microscale experiments in secondary education. Starting point are the vwo and havo levels (upper levels, pre-university and higher general secondary education), while vbo and mavo (vocational education) will follow in a later phase.

    The Government and the Chemical Industry are financially supporting this national project. Sets consisting of microscale glassware and student booklets are offered to the schools at a reasonable price. The educational material is consistent with the leading textbooks. The material enables students to carry out organic chemistry experiments on their own in a safe and clean way. Also, teachers and their lab assistants receive ongoing training in the use of microscale experiments

    The glassware

    The microscale glassware is reasonably priced and, by using the flexible coupling pieces, students can easily build setups. All usual operations can be done: reflux of reaction substances, separation of reaction products by means of distillation, sublimation, crystallization and column chromatography.

    Note that water-cooling is not necessary: faucets, hoses and drainage are therefore no longer necessary. The glassware itself is highly durable as it is relatively thick and light. Years of use in university labs have proven this durability. It is the quality as the Borosilicate glass used in larger chemistry glassware.
     
     

    the glassware kit
    Click this picture for a description of the kit (in Dutch)

    Microscale glassware comes in a small kit. A sand bath which we especially developed for this purpose accompanies the set. This heating method is low cost, safe and fast. A wall plug is the only prerequisite to work with the experiments: a fume cupboard is hardly ever necessary.

    the heating device
    Click this picture for an article on the heating device (in Dutch)

    A digital multi-meter with thermocouple will possible become the newest addition to the set. The set currently comes with a large mercury-free thermometer. Large, because it needs to have a large range (-10 °C - + 250 °C) as well as be easily read. As a consequence, it doesn't fit the set to scale. The digital multimeter might be a good alternative. We are currently testing it. While the price is already very favorable, we obtained a discount for our project members. Meanwhile, we continue to supply the mercury-free thermometers with the sets.

    The teaching material

    Each microscale set is accompanied by two sets of student booklets containing various microscale experiments. The student booklets are loose-leaf; this allows the distribution of single forms and easy replacement of dirty, well-used sheets by copies. It also permits continuous additions to and updates of the experiments. This will happen on a regular basis during this project.

    The microscale experiments match the two most widely used Dutch textbooks (Chemie and Chemie Overal); however, instead of demonstration experiments, student lab experiments are described. When no experiments are described in the texts, suggestions are made. The choice of experiments is also based on these two books. However, suggestions when and where to apply the experiments are also made for those who use different textbooks. New experiments will continuously be developed.

    As organic chemistry experiments are not very popular, the concerning chapters only contain a few experiments for the students. This is why we started with this type of experiment. However, we certainly will not be limited to them. Inorganic, analytical and physical chemistry microscale experiments can also be done with the glassware. When developing new experiments we incorporate as much as possible the demands of the users. The teaching material thus provides the teacher with a larger repertoire of experiments. Finally, the educational publishers have also expressed a great interest in microscale experiments; we expect that in their new editions they will incorporate these experiments.

    The first version of the teaching material contains some basic techniques as well as experiments like: Saturated and unsaturated hydrocarbons - Differentiation of isomers: alcohol and ethers  - Differentiation of isomeric alcohol's -  Esters: fragrances and taste.
     

    We are currently developing new experiments. Among others, these involve the isolation of natural products and the synthesis of dyes. They will be distributed to all project members. The experiments are stand-alone but can also be a part of a larger project incorporated in the profile paper. As profile papers need to involve at least two school-subjects, we are developing experiments which also have a biological aspect. This could be the hydrolysis of protein, preparation and testing of a sunscreen lotion or a biotechnology feature.

    Project membership

    Members of the project receive a teacher's manual and will be instructed in using the glassware. The teacher's manual describes the use of the microscale glassware and heating element. It also explains the experiments and their place in the curriculum.

    The instruction of teachers and their lab assistants will be held regionally as much as possible and will take half a day. However, the membership encompasses more: members will receive new additions to the teaching material. Next to this, a web site has been developed. Here, members can exchange experiences and read the latest news.

    Costs

    Microscale experiments are low cost because of
    - the low price of the microscale glassware compared to the conventional,
    - the decrease in chemicals used, and
    - the limited requirements of the 'lab'.

    Thanks to the subsidies of the government (the ministries of economic affairs, education and environment) and the financial support of the industry (The Dutch Chemical Association), it has been possible to supply the sets at a low price through the beginning of 1998.

    If the purchase of the necessary sets (one set per two students) still presents too high a burden on the school's budget, the University of Amsterdam offers the possibility to spread payments over three years against a low interest rate.

    See the prijslijst for details.

    Summary of Advantages

  • Increase in experiments repertoire
  • Decrease in use of chemicals, therefore cost saving
  • Less waste, therefore more ecologically sound
  • Smaller amounts of chemicals, therefore safer for the students
  • Faster processes, therefore more possibilities for organic experiments
  • Setups are easily built by the students, therefore more independent experimentation
  • No water hoses or cooling and no use of natural gas. Even a fume cupboard is no longer required for most experiments. A wall plug is all that is necessary.
  • The glassware is low cost and, due to its small size, practically unbreakable.
  • Schools save on costs of larger standard glassware.
  • A safe, fast and low cost heating element.
  • Continuous additions to the teaching material.
  • Favorable financing available.

    • Need More information?

    For more information, please contact:
     

    Stichting MicroC3hem
    Nieuwe Achtergracht 129
    1018 WS Amsterdam
    Phone: **3120-5256583
    Fax: **3120-5256586

    E-mail: micro@chem.uva.nl

    Published: 8 July 1998