Calcium cyanamide

Henry's Law constant

Link to relevant study record(s)

Reference

Endpoint:

Henry's law constant

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Justification for type of information:

Upon dissolution in water calcium cyanamide is fast transformed to hydrogen cyanamide. Therefore, available information on cyanamide is used in the assessment of calcium cyanamide in a read-across approach.
For detailled description where read across is used/recommended and where it is preferrable to refain from read across, please see section 13.2 "read across justification for environmental endpoints" and "Scientific rationale for not using cyanamide as read-across substance for calcium cyanamide on toxicological endpoints"

Reason / purpose for cross-reference:

read-across source

Key result

H:

0 Pa m³/mol

Temp.:

20 °C

Atm. press.:

1 Bar

No remarks

Conclusions:

Henry's law constant for cyanamide is H=0.0000268 Pa x M³/mol

Upon dissolution in water calcium cyanamide is fast transformed to hydrogen cyanamide. Therefore, available information on cyanamide is used in the assessment of calcium cyanamide in a read-across approach.
For detailled description where read across is used/recommended and where it is preferrable to refain from read across, please see section 13.2 "read across justification for environmental endpoints" and "Scientific rationale for not using cyanamide as read-across substance for calcium cyanamide on toxicological endpoints"

Executive summary:

The Henry´s law constant is the ration of vapour pressure to solubility and is therefore a measure of the partition of a compound between air and water. The Volatility of cyanamide could be calculated from the vapour pressure, molecular weight and water solubility data. The Henry´s law constant calculated for cyanamide at 20°C was found to be H=0.0000268 Pa x M³/mol.

If the value of H is below 0.5 Pa x m³/mol, which is the case for cyanamide, the phase transition resistance lies almost totally in the liquid phase, i.e, the volatility is liquid-phase controlled. If the value of H is greater than 500 Pa x m³/mol, volatilization is vapour-phase controlled.

This information is used in a read-across approach in the assessment of the target substance.

For detailled description where read across is used/recommended and where it is preferrable to refain from read across, please see section 13.2 "read across justification for environmental endpoints" and "Scientific rationale for not using cyanamide as read-across substance for calcium cyanamide on toxicological endpoints"

Description of key information

Upon dissolution in water calcium cyanamide is fast transformed to hydrogen cyanamide. Therefore, available information on cyanamide is used in the assessment of calcium cyanamide in a read-across approach.

The Henry's law constant for cyanamide is H=0.0000268 Pa x M³/mol

Key value for chemical safety assessment

Henry's law constant (H) (in Pa m³/mol):

0

at the temperature of:

20 °C

Additional information

For detailled description where read across is used/recommended and where it is preferrable to refain from read across, please see section 13.2 "read across justification for environmental endpoints" and "Scientific rationale for not using cyanamide as read-across substance for calcium cyanamide on toxicological endpoints"