Freezing point depression Principle The freezing point of a solution is lower than that of the pure solvent. The depression of the freezing point can be determined experimentally using a suitable apparatus (cryoscopy). If the cryoscopy constants of the solvent are known, the molecular mass of the substance dissolved can be determined. Benefits - All relevant measured variables at a glance
- Experimentation made easy by intuitive operation
- With detailed experiment guide
Tasks - Determine the size of freezing point depression after dissolving a strong electrolyte (NaCl) in water.
- Determine the number of ions into which the electrolyte dissociates.
- Determine the molar mass of a non-electrolyte (hydroquinone) from the value of freezing point depression.
Learning objectives - Raoult's law
- Cryoscopic constant
- Chemical potential
- Gibbs-Helmholtz equation
- Concentration ratio
- Degree of dissociation
- Van't Hoff factor
Necessary accessories - Precision balance 620g/0.001g
Scope of delivery |
Magnetic stirring bar 30 mm, cylindrical
|
46299-02
|
1
| |
Supp.rod stainl.st.,50cm,M10-thr.
|
02022-20
|
1
| |
Right angle boss-head clamp
|
37697-00
|
2
| |
Universal clamp
|
37715-01
|
2
| |
Apparatus for freezing point depression
|
36821-00
|
1
| |
Gasket for GL25, 12mm hole, 10pcs
|
41243-03
|
1
| |
Temperature meter digital, 4-2
|
13618-00
|
1
| |
Sheath Thermocouple, NiCr-Ni, Type K, -40°C ... +1000°C
|
13615-06
|
2
| |
Protective sleeves f.temp.probe,2
|
11762-05
|
1
| |
Beakers, Boro, low form, various sizes
|
46057-00
|
1
| |
Bulb pipettes, various sizes
|
36581-00
|
1
| |
Pipettor
|
36592-00
|
1
| |
Wash bottle, plastic, 500 ml
|
33931-00
|
1
| |
Digital stopwatch, 24 h, 1/100 s and 1 s
|
24025-00
|
1
| |
Pellet press for calorimeter
|
04403-04
|
1
| |
Mortar w. pestle, 70ml, porcelain
|
32603-00
|
2
| |
Microspoon, steel
|
33393-00
|
1
| |
Spoon, special steel
|
33398-00
|
1
| |
Funnel, diameter = 50 mm, plastic (PP)
|
36890-00
|
1
| |
Weighing dishes, square shape, 84 x 84 x 24 mm, 500 pcs.
|
45019-50
|
1
| |
Pasteur pipettes, 250 pcs
|
36590-00
|
1
| |
Rubber caps, 10 pcs
|
39275-03
|
1
| |
Glass stirring rod, d = 8 mm, l = approx. 300 mm
|
40485-06
|
1
| |
Sodium chloride, 500 g
|
30155-50
|
1
| |
Hydroquinone 250 g
|
30089-25
|
1
| |
Denaturated alcohol (spirit for burning), 1000 ml
|
31150-70
|
1
| |
Water, distilled 5 l
|
31246-81
|
1
| |
Universal power supply, 600mA 3/4.5/5/6/7.5/9/12V, incl. 9 adaptors
|
11078-99
|
1
|
|
Service
