GB/T 21845-2008 Chemicals — Water solubility test
1 Scope
This standard specifies the scope, definitions and units, reference substances, test methods, data and reporting of water solubility test of chemicals.
This standard is applicable to the determination of water solubility of chemicals.
2 Terms and definitions
For the purposes of this standard, the following term and definition apply:
2.1
water solubility
water solubility of a substance is the saturation mass concentration of the substance in water at a given temperature. Water solubility is expressed in mass of solute per volume of solution. The SI unit is kg/m3 but g/L is commonly used
3 Reference substances
Reference substances do not need in this standard.
4 Test methods
4.1 Test conditions
The test is preferably run at 20°C ± 0.5°C. The chosen temperature should be kept constant in all relevant parts of the equipment.
4.2 Preliminary test
In a stepwise procedure, increasing volumes of water are added at room temperature to approximately 0.1g of the sample (solid substances must be pulverized) in a 10mL glass-stoppered measuring cylinder. After each addition of an amount of water, the mixture is shaken for 10 minutes and is visually checked for any undissolved parts of the sample. If, after addition of 10mL of water, the sample or parts of it remain undissolved, the experiment is continued in a 100mL measuring cylinder. The approximate solubility (g/L) is given in Table 1 below under that volume of water in which complete dissolution of the sample occurs. When the solubility is low, a long time may be required to dissolve a substance and at least 24 hours should be allowed. If, after 24 hours, the substance is still not dissolved, more time (up to 96 hours) should be allowed or further dilution should be attempted to ascertain whether the column elution method or flask method should be used.
Table 1 Approximate solubility table of substances to be tested in preliminary test
Foreword I
OECD Introduction II
1 Scope
2 Terms and definitions
3 Reference substances
4 Test methods
5 Data and reporting
Bibliography
Standard
GB/T 21845-2008 Chemicals - Water solubility test (English Version)
GB/T 21845-2008 Chemicals — Water solubility test
1 Scope
This standard specifies the scope, definitions and units, reference substances, test methods, data and reporting of water solubility test of chemicals.
This standard is applicable to the determination of water solubility of chemicals.
2 Terms and definitions
For the purposes of this standard, the following term and definition apply:
2.1
water solubility
water solubility of a substance is the saturation mass concentration of the substance in water at a given temperature. Water solubility is expressed in mass of solute per volume of solution. The SI unit is kg/m3 but g/L is commonly used
3 Reference substances
Reference substances do not need in this standard.
4 Test methods
4.1 Test conditions
The test is preferably run at 20°C ± 0.5°C. The chosen temperature should be kept constant in all relevant parts of the equipment.
4.2 Preliminary test
In a stepwise procedure, increasing volumes of water are added at room temperature to approximately 0.1g of the sample (solid substances must be pulverized) in a 10mL glass-stoppered measuring cylinder. After each addition of an amount of water, the mixture is shaken for 10 minutes and is visually checked for any undissolved parts of the sample. If, after addition of 10mL of water, the sample or parts of it remain undissolved, the experiment is continued in a 100mL measuring cylinder. The approximate solubility (g/L) is given in Table 1 below under that volume of water in which complete dissolution of the sample occurs. When the solubility is low, a long time may be required to dissolve a substance and at least 24 hours should be allowed. If, after 24 hours, the substance is still not dissolved, more time (up to 96 hours) should be allowed or further dilution should be attempted to ascertain whether the column elution method or flask method should be used.
Table 1 Approximate solubility table of substances to be tested in preliminary test
Contents of GB/T 21845-2008
Foreword I
OECD Introduction II
1 Scope
2 Terms and definitions
3 Reference substances
4 Test methods
5 Data and reporting
Bibliography
