#MELTING POINT MEASURE HOW TO#

The white LED illuminates the sample from the back, and the magnifier shows an enlarged view of the samples. Holes are drilled in the block for the capillary tubes and the thermocouple sensor. The soldering tip is removed and an aluminium block is attached in its place, connected by a bolt which has its head cut off. The soldering iron is the basis of the heating system, which is controlled by an SCR energy regulator. A digital meat thermometer as shown above can also be used. A cheaper model ( $ 6.00 ) which reads to ± 1 o C can be substituted if less accuracy is accepted. § This model gives readings to ± 0.1 o C, and has a DATA HOLD feature which is very convenient. I salvaged the case from an old compact disc player, cut and shut to a suitable size ( 260 mm x 170 mm x 75 mm ). * If you can use an existing case or make one, this will save some money. Metal case*, assorted screws & nuts, brackets, electrical terminals & wire, assorted screws $ 20.00 Aluminium Tubing, 10 mm ø x 150 mm $ 1.00 White LED 6000 mcd 5 mm ø Dimmer control $ 2.00 Digital Thermometer 0- 1300 oC x 0.1 oC Type K Thermocouple § $ 20.00 Rocker switch, SPST 220 V + SPST Toggle Switch $ 4.00 2 x Computer Cooling Fans, 40 mm ø ,12 V DC $ 4.00 Soldering iron 220 V 60 W Temperature Controlled ~400 C $ 18.00 Aluminium Heating Block, 30 mm x 20 mm x 20 mm $ 5.00 The following items are required ( approximate prices as found on eBay )

#MELTING POINT MEASURE HOW TO#

Here I describe how to build an apparatus which will do the job at very reasonable cost, while providing many of the features of the more expensive commercial versions. Prices for these items range from a few hundred up to several thousand dollars. Electrically heated melting point devices were introduced to reduce these risks, and there are now several designs on the market, ranging from a simple electrically heated metal block up to computer controlled automatic instruments which record the entire operation on a video camera. This method involves some hazards from the use of an open flame and the chance of spilling the hot liquid while the operator has their face next to the bath observing the sample. Originally the sample, contained in a 1.5 mm diameter glass capillary tube, was heated in a bath filled with mineral oil ( or sometimes concentrated sulphuric acid ) with a Bunsen burner until melting occurred, and the bath temperature read from a thermometer. The temperature at which a sample melts is indicative of the purity and identity of the substance.

Units can be calibrated by the user on their site or by the manufacturer/service organization.A very frequently performed operation in organic chemistry laboratories is the determination of the melting point of a solid specimen.Integral light and wide angle 8X viewing magnifier enhance sample observation, so that all 3 samples can be viewed without eye strain.Rotating viewing head and safety eye piece to protect against glare and hot zone.Adjustable arm with viewing magnifier can be folded away into the unit.3 Audible beeps indicate that the oven temperature is stable and ready for sample.Samples in 3 capillary tubes may be viewed simultaneously.Digital microprocessor with ☑☌ resolution provides fast warm-up and accurate temperature control.Push button controls are conveniently located to ensure that temperatures can be recorded without looking away from the sample.Membrane keypad with simple menus for intuitive use.The 1101D Mel-Temp® has power requirements of 115V and 50-60Hz. As a visual aid, the viewing head holds a viewing magnifier that offers 8X magnification.Īs a further convenience, the extension arm is completely collapsible and can be neatly folded away into the unit, so that the unit can be stored flat to save space.ĭigital Mel-Temp® comes supplied with a complimentary pack of 50 capillary tubes, its own power supply and power cable. It is ideal for multiple users, being ergonomically designed to ensure comfortable viewing for everyone, with a height-adjustable extension arm and a viewing head that may be rotated to suit each user. The updated Mel-Temp® Digital Melting Point Apparatus offers a quick and easy way to measure the melting points of samples at a budget price with a temperature resolution of ☑☌. A Basic, Economical Melting Point Instrument

Melting point measure