Determination method of crystallization point of organic chemical products (1)

This standard refers to the international standard ISO1392-1977 "Determination of Crystallization Point-General Method"

1 Subject content and scope of application

This standard specifies the method for determining the crystallization point of organic chemical products

This standard applies to organic chemical products whose crystallization point is in the range of -10 to 150°C

2 Method summary

Liquid or molten organic chemical products are cooled at normal pressure.

3 Reagents The reagents used in this standard, unless other requirements are specified, all use analytical reagents

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4 Instruments

General laboratory equipment and

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3 Crystallization tube: made of glass, with an outer diameter of 25mm, a wall thickness of 2mm, and a length of 150mm
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4 Protective tube: made of glass, with an inner diameter of 28mm or 38mm, a wall thickness of 2mm, and a length of 120mm
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5 Stopwatch
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6 Stirrer: glass rod (diameter 3mm), or stainless steel wire (diameter 1 ~ 3mm), the length is more than 160mm, wound into a ring at right angles to the shaft, the diameter is about 20mm
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See Figure 1
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Figure 1 Stirrer

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7 Heating bath: 400mL or 500mL beaker
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8 Cooling bath:

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1 400ml.
or 500ml beaker.

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2 Dewar flask: made of glass, with silver-plated inner wall, 500-600mL in volume
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9 Asbestos board cover: hard asbestos board, thickness 5-7mm
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