Salts & brines

Sodium carbonate · Na2CO3

Name: Sodium carbonate (Na2CO3) aqueous solution properties
Creator: ProcessConvert
License: https://creativecommons.org/licenses/by/4.0/

Sodium carbonate (Na2CO3) is a salt; this page gives computed density, dynamic viscosity and specific heat capacity for aqueous solutions from 2–14 wt% and 20–40 °C.

Values are computed from the Laliberté (2009) aqueous-electrolyte correlation and tabulated over 2–14 wt% and 20–40 °C.

Also known as: Soda ash, Washing soda (decahydrate), Disodium carbonate
CAS number: 497-19-8
Tabulated range: 2–14 wt% · 20–40 °C
Properties: Density · Dynamic viscosity · Specific heat capacity · Specific gravity

At 10 wt% · 20 °C

reference snapshot

Density: 1103.6kg/m³
Density: 1.1036g/cm³
Specific gravity: 1.106
Viscosity: 1.791cP
Specific heat: 3792J/kg·K

Explore

Read a value at any point

Move the sliders to interpolate between the tabulated grid points. The readout and chart never go outside the validated 2–14 wt% and 20–40 °C range, and every number is interpolated from the committed table below — nothing is computed from a chemistry model in your browser.

Interactive explorer

Values are interpolated between the tabulated grid points below — sliders stay within the validated 2–14 wt% and 20–40 °C range.

Concentration8 wt%

Temperature20 °C

Density: 1082.3 kg/m³
Density: 1.0823 g/cm³
Specific gravity: 1.084
Dynamic viscosity: 1.573 cP
Specific heat: 3850 J/kg·K

Density (kg/m³) vs wt% Na2CO3 at 20 °C — Sodium carbonate.

Why it matters

What the numbers tell you

At 10 wt% and 20 °C, aqueous sodium carbonate has a density of about 1104 kg/m³ (1.104 g/cm³) — roughly 1.11× the density of water. It also has a dynamic viscosity of about 1.791 cP, against roughly 1 cP for water at the same temperature, and a specific heat of about 3.79 kJ/kg·K, about 91% of water’s 4.18 kJ/kg·K. Those differences carry straight into volume-to-mass conversions, pump and pipe sizing, and the heat needed to change its temperature.

Common grades

A few working strengths

Properties at 20 °C for a handful of concentrations in everyday use, read from the committed grid (interpolated between tabulated points where a grade falls between them). The full table follows below.

wt% Na2CO3	°C	Density kg/m³	SG	Viscosity cP	Sp. heat J/kg·K
4	20	1040.2	1.042	1.242	3993
8	20	1082.3	1.084	1.573	3850
10	20	1103.6	1.106	1.791	3792
14	20	1147.0	1.149	2.391	3698

Sources

Where the numbers come from

Every value on this page is computed by a deterministic model — none is entered by hand. The generating method and the references it is checked against:

▸Laliberte, M. (2009). A Model for Calculating the Heat Capacity of Aqueous Solutions, with Updated Density and Viscosity Data. J. Chem. Eng. Data 54(6), 1725-1760. doi:10.1021/je8008123
▸CRC Handbook of Chemistry and Physics, 97th ed. (Haynes, ed., 2016) - Concentrative Properties of Aqueous Solutions (density and viscosity at 20 degC)
▸CRC Handbook of Chemistry and Physics - Aqueous Solubility of Inorganic Compounds at Various Temperatures (solubility bounds for the tabulated range)

Model: thermo==0.4.0 (chemicals==1.3.0) - Laliberte 2009 electrolyte correlation · Generated 2026-06-07

The committed data file for this page is published as JSON on GitHub under CC BY 4.0.

Validation

Checked against a cited value

The model is cross-checked at one independently cited reference point. The page is published only because this check passes.

Property / point	Density · 10 wt% · 20 °C
Cited reference value	1102.9 kg/m3
Model computed	1103.57 kg/m3
Error vs reference	0.061% (tolerance 1%)

CRC Handbook of Chemistry and Physics, 97th ed.. Haynes, W.M. (ed.), CRC Handbook of Chemistry and Physics, 97th ed. (CRC Press, 2016), Concentrative Properties of Aqueous Solutions, p. 5-129: 10.0 mass % Na2CO3 at 20 degC = 1.1029 g/cm3. Perry's Chemical Engineers' Handbook, 7th ed. (Table 2-86 Sodium Carbonate) brackets the same point with 8% = 1.0816 and 12% = 1.1244 at 20 degC.

Full tables

Every tabulated point

Rows are temperature (°C); columns are concentration (wt% Na2CO3). Read the cell at the intersection. Specific gravity is density divided by the model water reference of 998.2 kg/m³ at 20 °C.

Density — kg/m³

°C \ wt%	2	4	6	8	10	12	14
20	1019.2	1040.2	1061.2	1082.3	1103.6	1125.1	1147.0
25	1017.8	1038.6	1059.5	1080.5	1101.7	1123.2	1145.1
30	1016.2	1036.8	1057.5	1078.4	1099.6	1121.1	1143.0
35	1014.4	1034.8	1055.4	1076.2	1097.4	1118.9	1140.8
40	1012.4	1032.6	1053.1	1073.9	1095.0	1116.4	1138.4

Dynamic viscosity — cP (mPa·s)

°C \ wt%	2	4	6	8	10	12	14
20	1.114	1.242	1.393	1.573	1.791	2.059	2.391
25	0.986	1.096	1.224	1.376	1.560	1.783	2.059
30	0.880	0.975	1.086	1.216	1.372	1.562	1.794
35	0.792	0.875	0.971	1.084	1.219	1.382	1.580
40	0.717	0.790	0.875	0.974	1.092	1.233	1.404

Specific heat capacity — J/kg·K

°C \ wt%	2	4	6	8	10	12	14
20	4081	3993	3916	3850	3792	3742	3698
25	4080	3992	3916	3850	3793	3742	3698
30	4079	3992	3917	3851	3794	3743	3700
35	4079	3993	3918	3853	3795	3745	3701
40	4080	3994	3920	3855	3797	3747	3703

Typical values

Sodium carbonate solution properties at 25 °C

At 25 °C, 4 wt% sodium carbonate has a density of about 1038.6 kg/m³, a dynamic viscosity of about 1.096 cP and a specific heat capacity of about 3992 J/kg·K. At 25 °C, 10 wt% sodium carbonate has a density of about 1101.7 kg/m³, a dynamic viscosity of about 1.560 cP and a specific heat capacity of about 3793 J/kg·K. At 25 °C, 14 wt% sodium carbonate has a density of about 1145.1 kg/m³, a dynamic viscosity of about 2.059 cP and a specific heat capacity of about 3698 J/kg·K.

Limitations

Before you use these numbers

▸Laliberte (2009) aqueous-electrolyte correlation for Na2CO3-water. Tabulated for 2-14 wt% over 20-40 degC. Sodium carbonate solubility falls steeply toward low temperature (about 18 wt% at 20 degC but only 11 wt% at 10 degC), so the table floor is held at 20 degC and the ceiling at 14 wt% to keep every tabulated point below saturation with margin. Concentrations are anhydrous Na2CO3 (soda ash); washing soda is the decahydrate, 37% Na2CO3 by mass. Values are for preliminary design; verify against vendor data for critical service.
▸Values are tabulated only inside the 2–14 wt% and 20–40 °C ranges shown; the correlation is not extrapolated beyond them here.
▸Figures are for a pure sodium carbonate–water system. Commercial grades contain impurities (for example chloride in some caustic grades) that shift density and viscosity; check the supplier's data sheet for a specific product.
▸Use for preliminary design; verify for critical service.

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