“No”. “Boring lesson then”.
“Not in the least, chemistry is never boring”.
“Sir is being daft again”.
Of course some students think that if they now have carte blanche to burn all their possessions, such as plastic pens, to see what happens, ie, they can mess about. That is why they like it.
The Bunsen burner has a powerful and expensive hold in UK practical chemistry. Its presence in practical work ultimately defines the set out of the school laboratory.
“Not in the least, chemistry is never boring”.
“Sir is being daft again”.
Of course some students think that if they now have carte blanche to burn all their possessions, such as plastic pens, to see what happens, ie, they can mess about. That is why they like it.
The Bunsen burner has a powerful and expensive hold in UK practical chemistry. Its presence in practical work ultimately defines the set out of the school laboratory.
The best option is to lay the servcies under the floor to rise up secure bollards sullpying, gas, water and electricity.
A cheaper option is to place the gas pipes (and other services) around the outside of the room, with just tables and chairs in the middle. The raison d’être for this is that labs should be adaptable to all types of teaching approaches with tables moving around, to accommodate group work and argumentation. How often I wonder does room alteration happen? With services around the perimeter and in terms of practical work, students now have their backs to the teacher when using the dangerous Bunsen, it is not possible to place 30 students around the perimeter and there are obstructions such as cupboards and notice boards with bits of paper on them.
I know that to rduce costs further, gas might be removed from labs altogether!
I have even see labs with no demonstration bench and have been told that this is to discourage demonstration because it is too teacher-centric. (No it is cheaper not to have services under the floor to the teacher’s bench!)
A cheaper option is to place the gas pipes (and other services) around the outside of the room, with just tables and chairs in the middle. The raison d’être for this is that labs should be adaptable to all types of teaching approaches with tables moving around, to accommodate group work and argumentation. How often I wonder does room alteration happen? With services around the perimeter and in terms of practical work, students now have their backs to the teacher when using the dangerous Bunsen, it is not possible to place 30 students around the perimeter and there are obstructions such as cupboards and notice boards with bits of paper on them.
I know that to rduce costs further, gas might be removed from labs altogether!
I have even see labs with no demonstration bench and have been told that this is to discourage demonstration because it is too teacher-centric. (No it is cheaper not to have services under the floor to the teacher’s bench!)
Students either use the yellow “safe” flame or the full-on blast. Control of adjuting the hreating by using air collar and gas tap is not so common. Even less common is that you can hold a Bunsen by the base and heat a liquid gently from the side. This is really important in distillation.
So is electrical heating an alternative to the Bunsen?
The electrical heating mantle and hotplates cost over £100 each, they are expensive and they take a long time to warm up a liquid (there is a fixed time to a lesson!) and they are impossible to use when heating test tubes. I have used a kitchen hotplate with a sand tray for heating small vials and small volumes of liquid in a test tube.
The temperature of the hottest flame is about 900ᵒC, enough to completely soften soda glass (and the heat shock causes catastrophic breakages) and distort borosilicate glass. At that temperature, calcium carbonate decomposes but so do sulfates (to sulfur dioxide and trioxide) and even sodium nitrate to brown nitrogen dioxide; an observation not in the text book (is this supposed to happen?) I am always uncomfortable directly distilling a flammable organic solvent from a pear-shaped Quickfit flask, but it has to be done sometimes (cyclohexanol to cyclohexene). Thus I try in school chemistry practicals, to suggest procedures that use boiling water baths or water from electric kettles.
I have been informed that many children (and some teachers) are very scared of lighting a flame such that neither will use them at GCSE level. Sometimes, it is the teacher only who lights the Bunsen for the student. There have been minor burns reported to CLEAPSS and parents and employers have questioned why we use such dangerous equipment. However, knowing how to deal safely with fire is good education! Also the most serious incident to harm a student was caused by a candle!
So when I suggest that I can do most of my chemistry with a spirit burner and an electric kettle, the traditionalists are horrified.
So is electrical heating an alternative to the Bunsen?
The electrical heating mantle and hotplates cost over £100 each, they are expensive and they take a long time to warm up a liquid (there is a fixed time to a lesson!) and they are impossible to use when heating test tubes. I have used a kitchen hotplate with a sand tray for heating small vials and small volumes of liquid in a test tube.
The temperature of the hottest flame is about 900ᵒC, enough to completely soften soda glass (and the heat shock causes catastrophic breakages) and distort borosilicate glass. At that temperature, calcium carbonate decomposes but so do sulfates (to sulfur dioxide and trioxide) and even sodium nitrate to brown nitrogen dioxide; an observation not in the text book (is this supposed to happen?) I am always uncomfortable directly distilling a flammable organic solvent from a pear-shaped Quickfit flask, but it has to be done sometimes (cyclohexanol to cyclohexene). Thus I try in school chemistry practicals, to suggest procedures that use boiling water baths or water from electric kettles.
I have been informed that many children (and some teachers) are very scared of lighting a flame such that neither will use them at GCSE level. Sometimes, it is the teacher only who lights the Bunsen for the student. There have been minor burns reported to CLEAPSS and parents and employers have questioned why we use such dangerous equipment. However, knowing how to deal safely with fire is good education! Also the most serious incident to harm a student was caused by a candle!
So when I suggest that I can do most of my chemistry with a spirit burner and an electric kettle, the traditionalists are horrified.
,Robert Bunsen, with his University Instrument Maker (ie his technician), Peter Desaga, see http://www.rsc.org/chemistryworld/Issues/2007/October/ClassicKitBunsenBurner.asp, designed the burner for a specific purpose. In a similar way you should ask yourself “is a Bunsen burner really required for this experiment? Its use is a part of risk assessment under the UK COSHH Regulations.
Are we using the Bunsens today?
“No”.
“Boring lesson then”.
“No I have done a risk assessment I find that hot water from a kettle is quicker and safer to react copper oxide with dilute sulfuric acid.”
“Do you usually talk like this?”
Are we using the Bunsens today?
“No”.
“Boring lesson then”.
“No I have done a risk assessment I find that hot water from a kettle is quicker and safer to react copper oxide with dilute sulfuric acid.”
“Do you usually talk like this?”
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