Salts & brines

Iron(III) chloride · FeCl3

Name: Iron(III) chloride (FeCl3) aqueous solution properties
Creator: ProcessConvert
License: https://creativecommons.org/licenses/by/4.0/

Iron(III) chloride (FeCl3) is a salt; this page gives computed density and dynamic viscosity for aqueous solutions from 2–40 wt% and 0–35 °C.

Values are computed from the Laliberté (2009) aqueous-electrolyte correlation and tabulated over 2–40 wt% and 0–35 °C.

Also known as: Ferric chloride, Iron trichloride
CAS number: 7705-08-0
Tabulated range: 2–40 wt% · 0–35 °C
Properties: Density · Dynamic viscosity · Specific gravity · Degrees Baumé

At 20 wt% · 20 °C

reference snapshot

Density: 1182.4kg/m³
Density: 1.1824g/cm³
Specific gravity: 1.185
Viscosity: 2.507cP
°Baumé: 22.6heavy

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 2–40 wt% and 0–35 °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 2–40 wt% and 0–35 °C range.

Concentration21 wt%

Temperature20 °C

Density: 1192.9 kg/m³
Density: 1.1929 g/cm³
Specific gravity: 1.195
Dynamic viscosity: 2.657 cP
°Baumé (heavy): 23.7

Density (kg/m³) vs wt% FeCl3 at 20 °C — Iron(III) chloride.

Why it matters

What the numbers tell you

At 20 wt% and 20 °C, aqueous iron(III) chloride has a density of about 1182 kg/m³ (1.182 g/cm³) — roughly 1.18× the density of water. It also has a dynamic viscosity of about 2.507 cP, against roughly 1 cP for water at the same temperature. Those differences carry straight into volume-to-mass conversions, pump and pipe sizing.

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% FeCl3	°C	Density kg/m³	SG	Viscosity cP	°Baumé
10	20	1084.8	1.087	1.534	11.6
20	20	1182.4	1.185	2.507	22.6
30	20	1292.5	1.295	4.618	33.0
40	20	1416.2	1.419	9.378	42.8

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)
▸International Critical Tables, Vol. III (1928) - FeCl3 density table, p. 68 (cross-check)
▸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 · 20 wt% · 20 °C
Cited reference value	1181.6 kg/m3
Model computed	1182.42 kg/m3
Error vs reference	0.07% (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. 5-123: 20.0 mass % iron(III) chloride at 20 degC = 1.1816 g/cm3. Cross-checked against International Critical Tables Vol. III, p. 68 (1.1820) and Solvay ferric chloride solution density data, PCH-1610-0001 (1.183).

Full tables

Every tabulated point

Rows are temperature (°C); columns are concentration (wt% FeCl3). 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	16	18	20	22	24	26	28	30	32	34	36	38	40
0	1016.6	1033.9	1051.5	1069.6	1088.1	1107.0	1126.5	1146.4	1166.8	1187.7	1209.1	1231.0	1253.5	1276.5	1300.0	1324.1	1348.8	1374.1	1399.9	1426.3
5	1016.7	1033.8	1051.4	1069.3	1087.8	1106.6	1126.0	1145.8	1166.1	1186.9	1208.2	1230.0	1252.3	1275.2	1298.6	1322.5	1347.1	1372.2	1397.8	1424.1
10	1016.3	1033.4	1050.9	1068.8	1087.1	1105.9	1125.1	1144.8	1165.0	1185.7	1206.9	1228.5	1250.8	1273.5	1296.8	1320.6	1345.0	1370.0	1395.5	1421.6
15	1015.7	1032.6	1050.0	1067.8	1086.1	1104.8	1123.9	1143.5	1163.6	1184.2	1205.3	1226.8	1248.9	1271.6	1294.7	1318.5	1342.7	1367.6	1393.0	1419.0
20	1014.7	1031.6	1048.9	1066.6	1084.8	1103.4	1122.4	1141.9	1161.9	1182.4	1203.4	1224.9	1246.9	1269.4	1292.5	1316.1	1340.2	1365.0	1390.3	1416.2
25	1013.5	1030.3	1047.5	1065.2	1083.2	1101.7	1120.7	1140.1	1160.0	1180.4	1201.3	1222.7	1244.6	1267.0	1290.0	1313.5	1337.6	1362.2	1387.4	1413.2
30	1012.0	1028.7	1045.9	1063.5	1081.5	1099.9	1118.8	1138.1	1157.9	1178.2	1199.0	1220.3	1242.2	1264.5	1287.4	1310.8	1334.8	1359.3	1384.5	1410.2
35	1010.3	1027.0	1044.1	1061.6	1079.5	1097.8	1116.6	1135.9	1155.7	1175.9	1196.6	1217.8	1239.6	1261.8	1284.6	1308.0	1331.9	1356.3	1381.4	1407.0

Dynamic viscosity — cP (mPa·s)

°C \ wt%	2	4	6	8	10	12	14	16	18	20	22	24	26	28	30	32	34	36	38	40
0	1.960	2.146	2.352	2.582	2.840	3.134	3.473	3.868	4.334	4.887	5.550	6.349	7.314	8.481	9.898	11.62	13.73	16.36	19.66	23.92
5	1.660	1.814	1.984	2.172	2.384	2.625	2.901	3.221	3.597	4.041	4.570	5.202	5.960	6.869	7.960	9.272	10.86	12.80	15.22	18.29
10	1.426	1.555	1.697	1.855	2.032	2.232	2.461	2.726	3.035	3.398	3.828	4.340	4.948	5.671	6.530	7.553	8.777	10.26	12.07	14.34
15	1.240	1.350	1.471	1.605	1.755	1.924	2.117	2.339	2.598	2.900	3.256	3.677	4.174	4.760	5.451	6.265	7.227	8.376	9.768	11.49
20	1.090	1.185	1.289	1.405	1.534	1.678	1.843	2.032	2.251	2.507	2.806	3.158	3.570	4.054	4.618	5.277	6.049	6.959	8.049	9.378
25	0.967	1.050	1.141	1.242	1.353	1.479	1.621	1.784	1.972	2.191	2.446	2.744	3.091	3.496	3.964	4.506	5.135	5.868	6.737	7.784
30	0.865	0.938	1.018	1.107	1.205	1.315	1.439	1.581	1.745	1.934	2.153	2.409	2.705	3.048	3.442	3.894	4.413	5.013	5.716	6.554
35	0.779	0.844	0.916	0.994	1.081	1.178	1.288	1.413	1.556	1.722	1.913	2.134	2.390	2.683	3.019	3.401	3.835	4.332	4.909	5.589

Typical values

Iron(III) chloride solution properties at 25 °C

At 25 °C, 10 wt% iron(III) chloride has a density of about 1083.2 kg/m³ and a dynamic viscosity of about 1.353 cP. At 25 °C, 30 wt% iron(III) chloride has a density of about 1290.0 kg/m³ and a dynamic viscosity of about 3.964 cP. At 25 °C, 40 wt% iron(III) chloride has a density of about 1413.2 kg/m³ and a dynamic viscosity of about 7.784 cP.

Limitations

Before you use these numbers

▸Laliberte (2009) aqueous-electrolyte correlation for FeCl3-water, density and viscosity only: the published data set behind the correlation carries no heat-capacity coefficients for FeCl3, so heat capacity is not tabulated rather than approximated. Tabulated for 2-40 wt% over 0-35 degC, the correlation's fitted window for FeCl3; saturation is about 43 wt% at 0 degC, so the whole table sits below saturation. Ferric chloride solutions are commonly traded on the heavy Baume scale, so degrees Baume are shown. Values are for preliminary design; verify against vendor data for critical service.
▸Values are tabulated only inside the 2–40 wt% and 0–35 °C ranges shown; the correlation is not extrapolated beyond them here.
▸Figures are for a pure iron(III) chloride–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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