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EC number: 200-081-4 | CAS number: 51-17-2
Endpoint summary
Administrative data
Description of key information
Appearance / physical state / colour:
On the basis of physical observation, the chemical Benzimidazole (CAS No. 51-17-2) was observed to be off white colored crystalline powder in appearance.
Melting point/ Freezing point:
The Mean Melting temperature range of Benzimidazole (CAS No. 51-17-2) was found be 158.83 - 166°C at 977 hPa.
Boiling point:
The boiling point of Benzimidazole (CAS No. 51-17-2) is determined to be greater than 250°C at 973.4 hPa.
Density:
The mean density of Benzimidazole (CAS No. 51-17-2) was found to be 0.947 g/cm³ at 20°C and 974 hPa.
Particle size distribution (Granulometry):
The particle size distribution of test item Benzimidazole (CAS No. 51-17-2) was determined by granulometric analysis with rotap sieve shaker. The particle size distribution was determined to be in the range of 150 micron to 25 micron.
Vapour pressure:
The estimated vapour pressure of Benzimidazole (CAS No. 51-17-2) at 25°C was 0.010186 Pa (7.64E-5 mm Hg)
Partition coefficient:
The partition coefficient (n-octanol/water) of test substance 1H-benzimidazole was determined as per the HPLC method (OECD Guideline-117). The Log Pow value was determined to be 3.626 dimensionless at 25°C. This value indicates that the substance 1H-benzimidazole is hydrophilic in nature.
Water solubility:
The water solubility for the test item Benzimidazole (CAS no. 57-17-2) was found to be 6320.46 mg/L at 30°C.
Surface tension:
Based on the data from ACD labs, surface tension for benzimidazole was predicted to be 60.1 ± 3.0 dyne/cm.
Flash point:
The mean flash point of Benzimidazole (CAS No. 51-17-2) is greater than 250°C at 976.2 hPa.
Autoflammability:
Benzimidazole (CAS No. 51-17-2) did not catch fire on being exposed to air at room temperature of 27°C and atmospheric pressure of 966 hPa. This indicates that Benzimidazole (CAS No. 51-17-2) is not auto-flammable.
Flammability:
Benzimidazole (CAS No. 51-17-2) does not indicate any ignition when the flame of bunsen burner having temperature of approximately 950°C is brought in contact with it. Thus it can be concluded that Benzimidazole (CAS No. 51-17-2) is not flammable at high temperature. However since such high temperatures are not found under normal circumstances of transportation and use, thus Benzimidazole (CAS No. 51-17-2) was considered as non-flammable.
Explosiveness:
The study does not need to be conducted because there are no chemical groups present in the molecule which are associated with explosive properties.
Oxidising properties:
The study does not need to be conducted because there are no chemical groups present in the molecule which are associated with oxidizing properties and hence the classification procedure does not need to be applied.
pH:
The pH of 1% w/v dispersion of the test item Benzimidazole (CAS No 51-17-2) was 8.11 at 30 °C.
Viscosity:
In accordance with Section 2 of REACH Annex XI, information requirement section 7.17, this study cannot be conducted on solid materials or gases. According to ECHA Chapter 7 guidance, viscosity measurement is only relevant to liquids. The Benzimidazole (CAS No 51-17-2) is a off white solid crystalline powder. Hence this study can be considered for waiver.
Additional information
Appearance / physical state / colour:
On the basis of physical observation, the chemical Benzimidazole (CAS No. 51-17-2) was observed to be off white colored crystalline powder in appearance.
Other supporting data from various handbooks and authoritative databases, also observed the appearance of Benzimidazole (CAS No. 51-17-2) as an organic solid present as tabular crystals or plates and in solid crystalline form.
Melting point/ Freezing point:
The melting point determination of Benzimidazole (CAS No. 51-17-2) was done following OECD Guideline 102 and according to the metal block capillary method. The test was conducted in replicates and Mean Melting temperature range was determined to be 158.83 - 166°C at 977 hPa.
Other supporting data from various reliable handbooks and authoritative databases, also determined the melting point of Benzimidazole (CAS No. 51-17-2) as 170.5 degree C, 172 degree to 174 degree C, 172.2 degree C and 170 degree C to 172 degree C respectively.
Boiling point:
The boiling point determination of Benzimidazole (CAS No. 51-17-2) was done following OECD Guideline 103 and according to the method of Siwoloboff. The boiling point was found to be greater than 250°C at 973.4 hPa.
Other supporting data from various reliable handbooks and authoritative databases, also determined the boiling point of chemical Benzimidazole as >360 degree C.
Density:
The density of substance Benzimidazole (CAS No. 51-17-2)was determined following OECD Guideline 109 and according to the method adapted from ASTM D 854-02. The mean density of the substance benzimidazole was determined to be 0.947 g/cm3 at 20°C and 974 hPa.
Other supporting datafrom authoritative database Scifinder, also estimated the density of chemical Benzimidazole (CAS no. 51-17-2) as 1.227 g/cm3.
Particle size distribution (Granulometry):
The particle size distribution of test item Benzimidazole (CAS No. 51-17-2) was determined by granulometric analysis with rotap sieve shaker. The particle size distribution was determined to be in the range of 150 micron to 25 micron.
Vapour pressure:
Based on available data from handbook and authoritative databases, estimated vapour pressure of Benzimidazole (CAS No. 51-17-2) at 25°C was 0.010186 Pa (7.64E-5 mm Hg).
Other supporting data from MPBPVP v1.43 (EPI Suite) also estimated the vapour pressure of Benzimidazole (CAS No. 51-17-2)
at 25°C as 0.00138 Pa (1.03E-005 mm Hg).
Partition coefficient:
The partition Coefficient n-octanol/water of test chemical 1H-benzimidazole was determined by the Reverse Phase High Performance Liquid Chromatographic method according to OECD Guideline No. 117 for testing of Chemicals. The reference substances were chosen according to estimated Pow range of the test substance and generalized calibration graph was prepared.
The reference substances were 4-Acetylpyridine, Benzene, Biphenyl, Toluene, Ethylbenzene, Naphthalene, n-Butylbenzene having Pow value ranging from 0.5 to 4.6
The Log Pow value was determined to be 3.626 dimensionless at 25°C.
This value indicates that the substance 1H-benzimidazole is hydrophilic in nature.
Water solubility:
The water solubility determination of test item Benzimidazole (CAS No. 51-17-2) was done as per the OECD guideline 105 and by spectrophotometric analytical method as per OECD 101. The solubility of Benzimidazole (CAS: 51-17-2 ) in water was determined to be 6320.46 mg/L at 30°C.
Hence, on the basis of experimental value the Benzimidazole (CAS No. 51-17-2) is considered to be soluble in water.
Surface tension:
Based on the data from ACD labs, surface tension for benzimidazole was predicted to be 60.1 ± 3.0 dyne/cm.
Flash point:
The flash point determination of Benzimidazole (CAS No. 51-17-2) was done following closed cup method using Pensky-Martens flash point apparatus. The test was conducted in replicates and mean flash point was determined to be greater than 250°C at 976.2 hPa.
Based on criteria mentioned in CLP regulation the chemical has flash point >than 60 degree C hence the Benzimidazole (CAS No. 51-17-2) was considered to be non-flammable.
Autoflammability:
Benzimidazole (CAS No. 51-17-2) did not catch fire on being exposed to air at room temperature of 27°C and atmospheric pressure of 966 hPa. This indicates that Benzimidazole (CAS No. 51-17-2) is not auto-flammable.
Flammability:
Benzimidazole (CAS No. 51-17-2) does not indicate any ignition when the flame of bunsen burner having temperature of approximately 950°C is brought in contact with it. Thus it can be concluded that Benzimidazole (CAS No. 51-17-2) is not flammable at high temperature. However since such high temperatures are not found under normal circumstances of transportation and use, thus Benzimidazole (CAS No. 51-17-2) was considered as non-flammable.
Explosiveness:
The study does not need to be conducted because there are no chemical groups present in the molecule which are associated with explosive properties.
Oxidising properties:
The study does not need to be conducted because there are no chemical groups present in the molecule which are associated with oxidizing properties and hence the classification procedure does not need to be applied.
pH:
The pH determination of test item Benzimidazole (CAS No 51-17-2) was done following OECD guideline 122. pH of 1% w/v dispersion was measured with the help of pH meter and it was observed to be 8.11 at 30°C.
Viscosity:
In accordance with Section 2 of REACH Annex XI, information requirement section 7.17, this study cannot be conducted on solid materials or gases. According to ECHA Chapter 7 guidance, viscosity measurement is only relevant to liquids. The Benzimidazole (CAS No 51-17-2) is a off white solid crystalline powder. Hence this study can be considered for waiver.
Information on Registered Substances comes from registration dossiers which have been assigned a registration number. The assignment of a registration number does however not guarantee that the information in the dossier is correct or that the dossier is compliant with Regulation (EC) No 1907/2006 (the REACH Regulation). This information has not been reviewed or verified by the Agency or any other authority. The content is subject to change without prior notice.
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