Upload
others
View
4
Download
0
Embed Size (px)
Citation preview
CLEAPSS www.cleapss.org.uk
CLEAPSS provides
• health and safety including model risk assessments,
• chemicals, living organisms, equipment,
• sources of resources,
• laboratory design, facilities and fittings,
• technicians and their jobs,
• D&T facilities and fittings.
It has around 2000 associate members, ie:
Local government schools
Independent state and fee paying schools
Colleges of Further Education
Overseas institutions,
Teacher-training establishments and learned bodies such as the Royal Society for Chemistry, Science learning centres, Field centres, museums, etc,
Examination centres and Curriculum developers.
CLEAPSS provides Termly newsletters for primary and secondary schools,
a wide range of free publications,
model and special risk assessments,
low-cost training courses for technicians, teachers and local authority officers,
a telephone Helpline which takes almost 7000 calls per year a monitoring service, eg, for mercury spills,
evaluations of equipment and advice on repairs,
Assistance to Government and Quasi-government institutions (eg Health & safety Executive)
a H&S / Review service for publishers, exam boards and other organisations producing teaching resources.
Microscale chemistry approach • Allowing the teaching of chemistry in
developing countries
• Instigating green & environmental issues
Microelectrolysis
Drop Chemistry
Working with toxic gases, no fume cupboard/hood required.
And uses smaller volumes of chemicals
Disposal not such a great issue
•Improves classroom management
But let’s look at issues which are less obvious at first but may be more important
Seated students
Improves classroom management
Balances
Dropping bottles
Students work more efficiently allowing the teacher more time to teach
• Improves classroom management
•Aids improved understanding of difficult chemical concepts leading to visualization of models
But let’s look at isssues which are less obvious at first but may be more important
The Johnstone triangle of the facets of chemical knowledge: students must learn in three different representations at once, and how to inter-relate each new concept or fact in all three domains. Here I have expanded the triangle into a rectangles by adding RELEVANCE
Aids improved understanding of difficult chemical concepts leading to visualization of models
Diffusion of gases and particulate theory of matter
Ammonia gas diffuses from the central
container to react with metal ions
Microelectrolysis of CuCl2 (aq) produces chlorine which reacts with KI(aq), KBr(aq) and moist blue litmus
Conductivity
Movement of ions
Evidence for the existence of ions
One grain of salt dissolved in the puddle can cause the solution to conduct indicated by the LED
Electrolysis of a molten salt
Diffusing precipitates
Solubility and precipitation
Chemistry is a battle of electrostatic attraction between particles carrying electrostatic charges • Ionic bonds • Covalent bonds • Intermolecular attraction • Solvent ion attraction
0 0.2 0.4 0.6 0.8 1 1.2
2
2.5
3
3.5
4
4.5
volume of acid
Cu
rre
nt
0.1M H2SO4 against 1 ml of 0.1M NaOH
Stoichiometry (work in process)
To 9v battery and multimeter
Microtitration technique
• Improves classroom management
• Helps students develop improved understanding of difficult chemical concepts
•Students work more efficiently allowing the teacher more time to teach. (Is this because there is a lower cognitive overload?)
But let’s look at isssues which are less obvious at first but may be more important
Perception filter where the senses operate to provide information
Short term working memory which can
hold a limited number of independent items. 7 items plus or minus 2
I can get information from my long-term memory to provide an
explanation.
Long term memory which is not large in students and teachers are trying to make it larger. This will hold both correct and incorrect interpretations of events.
Many different events will be-connected with each other, either correctly or incorrectly.
It also holds memories of common sense explanations but common sense may not always be correct.
As short term memory events are inserted from the working memory they may reinforce or contradict memories here.
Conflicts here can make me terribly confused!
Response back to teacher
Event happens
Cognitive load
Titration
Turn a clamp or a Hoffman clip to of drops of solution
• Use the microscale titration method to introduce the subject. Gradually move to the standard equipment.
• Acid base yes, but can also do redox, complexometric and precipitation
Complexometric titration of hard water
Measurements are made by weighing and assume all solutions have te same density
• Improves classroom management
• Helps students develop improved understanding of difficult chemical concepts
• Students work more efficiently allowing the teacher more time to teach. (Is this because there is a lower cognitive overload?)
•New and original experiments
But let’s look at isssues which are less obvious at first but may be more important
PARAMAGNETISM
Demonstration of paramagnetism in transition compounds with powerful neodymium magnets
MORE ALKENES Dehydration of propan-2-ol to make propene
Propene preparation.mp4
• Improves classroom management
• Helps students develop improved understanding of difficult chemical concepts
• Students work more efficiently allowing the teacher more time to teach. (Is this because there is a lower cognitive overload?)
• New and original experiments
•Brings to life important techniques
But let’s look at issues which are less obvious at first but may be more important
Gases in a Petrie dish
Colorimeter Gases in Syringes
Comboplate
Microtitration
Chemistry in a sealed Pasteur pipette
Chemistry on plastic sheet, Bottle-top, Crucibles and Microelectrolysis
Hoffman Voltameter, microelectroylsis
Spirit burner Conductivity tester
Bicycle spoke deflagrating spoon
Thank you to the world of microchemists
Portable organic chemistry set
Thanks •To Professor Supawan Tantayanon and her team
•To
•To CLEAPSS & Director Steve Jones
•Dr Kay Stephenson (ideas, improvement)
•Mary Owen, Jane Major and Emma Warwick (The CLEAPSS Technicians)