Sodium formate

Henry's Law constant

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

Henry's law constant

Type of information:

calculation (if not (Q)SAR)

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Scientifically acceptable publication

Reason / purpose for cross-reference:

read-across: supporting information

Qualifier:

no guideline followed

Principles of method if other than guideline:

Henry´s Law Constant was determined by measuring equilibrium partial pressures (dynamic method according to Scarano et al., 1971) for a series of known aqueous molalities.

H:

0.019 Pa m³/mol

Temp.:

25 °C

Conclusions:

The Henry's Law constant of formic acid was determined to be 0.019 Pa m³/mol at 25 °C.

Executive summary:

The Henry´s Law constant of formic acid was determined by measuring equilibrium partial pressures (dynamic method according to Scarano et al., 1971) for a series of known aqueous molalities, resulting in a value 0.019 Pa m³/mol at 25°C (Khan & Brimblecomb, 1992).

Reference 2

Endpoint:

Henry's law constant

Type of information:

(Q)SAR

Adequacy of study:

other information

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

other: Generally scientifically accepted method, but EPI Suite not validated for inorganic salts

Principles of method if other than guideline:

HENRY (v.3.10): Bond estimation method

H:

0 Pa m³/mol

Temp.:

25 °C

Remarks on result:

other: Calculated from vapor pressure and water solubility using EPI values

H:

0.076 Pa m³/mol

Temp.:

25 °C

Remarks on result:

other: Calculated using the Bond Contribution Method

Henry's Law Constant (HLC) at 25 °C calculated

1)

from vapor pressure (VP) and water solubility (Sol) using EPI values:

HLC = 6.83E-10 Pa*m³/mol

VP = 1.00E-07 hPa

Sol = 1.0E+06 mg/L

2)

using the Bond Contribution Method

HLC = 7.63E-02 Pa*m³/mol

Conclusions:

A Henry’s Law constant value of 0.0763 Pa m3/mol was estimated for sodium formate by the HENRYWIN (v3.20) QSAR in the EPISuite (v3.12) software using the Bond Contribution Method.

Executive summary:

A Henry’s Law constant (HLC) value of 0.0763 Pa m³/mol was estimated for sodium formate by the HENRYWIN (v3.20) QSAR in the EPISuite (v3.12) software using the Bond Contribution Method. However, this HLC value is not assignable since EPISuite is not validated for inorganic salts.

Reference 3

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:

It is considered appropriate to address the Henry’s Law constant data requirement for sodium formate by read-across to an available study on formic acid.
Sodium formate is the sodium salt of formic acid, and will dissociate immediately in aqueous and biological surroundings to the formate ion. It is therefore expected that the environmental profile of formic acid and sodium formate will be similar.

Reason / purpose for cross-reference:

read-across: supporting information

Specific details on test material used for the study:

Formic acid is being used as a read-across for sodium formate.

H:

0.019 Pa m³/mol

Temp.:

25 °C

Conclusions:

The Henry's Law constant of formic acid was determined to be 0.019 Pa m³/mol at 25°C, and is considered suitable for read-across to sodium formate.

Executive summary:

It is considered appropriate to address the Henry's Law constant data requirement for sodium formate by read-across to an available study on formic acid. Sodium formate is the sodium salt of formic acid, and will dissociate immediately in aqueous and biological surroundings to the formate ion. It is therefore expected that the environmental profile of formic acid and sodium formate will be similar.

 

The Henry´s Law constant of formic acid was determined by measuring equilibrium partial pressures (dynamic method according to Scarano et al., 1971) for a series of known aqueous molalities, resulting in a value 0.019 Pa m³/mol at 25°C (Khan & Brimblecomb, 1992). This value is therefore also considered for sodium formate.

Description of key information

The Henry’s Law Constant (HLC) value for sodium formate has been addressed via read-across from an available study on formic acid, given that sodium formate is the sodium salt of formic acid, and will dissociate immediately in aqueous and biological surroundings to the formate ion. It is therefore expected that the environmental profile of formic acid and sodium formate will be similar.

The Henry´s Law constant of formic acid was determined by measuring equilibrium partial pressures (dynamic method according to Scaranoet al., 1971) for a series of known aqueous molalities, resulting in a value 0.019 Pa m³/mol at 25°C (Khan & Brimblecomb, 1992). This value is therefore also considered for sodium formate.

Sodium formate will not evaporate from the water surface into the atmosphere.

Key value for chemical safety assessment

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

0.019

at the temperature of:

25 °C

Additional information

A read across was performed to formic acid in order to have a reliable value for the calculation of PNECsed and PNECsoil via the equilibrium partitioning method. The Henry's Law Constant (HLC) of formic acid was determined to be 0.019 Pa m³/mol at 25 °C (Khan & Brimblecomb, 1992).