Acids & bases

Hydrochloric acid · HCl

Name: Hydrochloric acid (HCl) aqueous solution properties
Creator: ProcessConvert
License: https://creativecommons.org/licenses/by/4.0/

Hydrochloric acid (HCl) is an acid; this page gives computed density, dynamic viscosity and specific heat capacity for aqueous solutions from 5–35 wt% and 0–60 °C.

Values are computed from the Laliberté (2009) aqueous-electrolyte correlation and tabulated over 5–35 wt% and 0–60 °C.

Also known as: Muriatic acid, Spirits of salt, Hydrogen chloride solution
CAS number: 7647-01-0
Tabulated range: 5–35 wt% · 0–60 °C
Properties: Density · Dynamic viscosity · Specific heat capacity · Specific gravity · Degrees Baumé

At 20 wt% · 20 °C

reference snapshot

Density: 1097.5kg/m³
Density: 1.0975g/cm³
Specific gravity: 1.099
Viscosity: 1.366cP
Specific heat: 2814J/kg·K
°Baumé: 13.1heavy

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 5–35 wt% and 0–60 °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 5–35 wt% and 0–60 °C range.

Concentration20 wt%

Temperature20 °C

Density: 1097.5 kg/m³
Density: 1.0975 g/cm³
Specific gravity: 1.099
Dynamic viscosity: 1.366 cP
Specific heat: 2814 J/kg·K
°Baumé (heavy): 13.1

Density (kg/m³) vs wt% HCl at 20 °C — Hydrochloric acid.

Why it matters

What the numbers tell you

At 20 wt% and 20 °C, aqueous hydrochloric acid has a density of about 1098 kg/m³ (1.097 g/cm³) — roughly 1.10× the density of water. It also has a dynamic viscosity of about 1.366 cP, against roughly 1 cP for water at the same temperature, and a specific heat of about 2.81 kJ/kg·K, about 67% 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% HCl	°C	Density kg/m³	SG	Viscosity cP	Sp. heat J/kg·K	°Baumé
10	20	1047.3	1.049	1.164	3489	6.8
20	20	1097.5	1.099	1.366	2814	13.1
30	20	1148.6	1.151	1.682	2155	19.0
35	20	1174.3	1.176	1.940	1829	21.7

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
▸Perry's Chemical Engineers' Handbook, 6th ed. (Perry & Green) - aqueous HCl density table (Solvay supplemental data)

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	1098 kg/m3
Model computed	1097.5 kg/m3
Error vs reference	0.045% (tolerance 1%)

Perry's Chemical Engineers' Handbook, 6th ed.. Perry, R.H. & Green, D.W. (eds.), Perry's Chemical Engineers' Handbook, 6th ed., aqueous hydrochloric acid density-concentration table (with supplemental Solvay data): 20 wt% HCl at 20 degC = 1.0980 g/cm3. Cross-checked against a published standard HCl density table giving 1.100 g/cm3 at 20 wt%, 20 degC.

Full tables

Every tabulated point

Rows are temperature (°C); columns are concentration (wt% HCl). 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%	5	10	15	20	25	30	35
0	1025.2	1051.0	1077.5	1104.4	1131.9	1160.0	1188.5
5	1025.0	1050.6	1076.6	1103.1	1130.0	1157.4	1185.1
10	1024.5	1049.7	1075.4	1101.4	1127.8	1154.6	1181.6
15	1023.7	1048.6	1073.9	1099.6	1125.5	1151.6	1178.0
20	1022.6	1047.3	1072.3	1097.5	1122.9	1148.6	1174.3
25	1021.3	1045.7	1070.4	1095.3	1120.3	1145.4	1170.6
30	1019.7	1044.0	1068.4	1093.0	1117.6	1142.3	1166.8
35	1018.0	1042.1	1066.3	1090.6	1114.9	1139.1	1163.2
40	1016.1	1040.1	1064.1	1088.2	1112.1	1136.0	1159.6
45	1014.0	1037.9	1061.8	1085.7	1109.4	1132.9	1156.1
50	1011.9	1035.7	1059.5	1083.2	1106.7	1129.9	1152.8
55	1009.6	1033.4	1057.1	1080.7	1104.1	1127.1	1149.7
60	1007.1	1031.0	1054.8	1078.3	1101.5	1124.4	1146.7

Dynamic viscosity — cP (mPa·s)

°C \ wt%	5	10	15	20	25	30	35
0	1.876	1.971	2.075	2.197	2.355	2.579	2.910
5	1.604	1.698	1.801	1.921	2.074	2.287	2.597
10	1.390	1.482	1.583	1.699	1.846	2.047	2.339
15	1.218	1.307	1.405	1.517	1.658	1.849	2.123
20	1.079	1.164	1.258	1.366	1.501	1.682	1.940
25	0.963	1.045	1.136	1.240	1.368	1.540	1.785
30	0.867	0.945	1.032	1.132	1.255	1.419	1.650
35	0.786	0.861	0.944	1.040	1.157	1.313	1.533
40	0.716	0.788	0.868	0.960	1.072	1.221	1.430
45	0.657	0.725	0.802	0.890	0.998	1.140	1.339
50	0.605	0.671	0.744	0.829	0.932	1.069	1.258
55	0.560	0.623	0.693	0.775	0.874	1.005	1.186
60	0.520	0.580	0.648	0.727	0.822	0.948	1.121

Specific heat capacity — J/kg·K

°C \ wt%	5	10	15	20	25	30	35
0	3843	3476	3115	2757	2404	2055	1709
5	3835	3476	3121	2770	2423	2080	1740
10	3832	3478	3129	2784	2443	2106	1771
15	3831	3483	3139	2800	2463	2131	1801
20	3832	3489	3150	2814	2483	2155	1829
25	3834	3494	3160	2829	2501	2177	1856
30	3836	3500	3169	2842	2518	2197	1879
35	3838	3506	3179	2854	2534	2216	1901
40	3841	3512	3187	2866	2548	2233	1921
45	3844	3517	3195	2876	2560	2248	1938
50	3847	3522	3202	2885	2572	2261	1953
55	3850	3527	3209	2894	2581	2272	1966
60	3853	3532	3215	2901	2590	2282	1976

Typical values

Hydrochloric acid solution properties at 25 °C

At 25 °C, 10 wt% hydrochloric acid has a density of about 1045.7 kg/m³, a dynamic viscosity of about 1.045 cP and a specific heat capacity of about 3494 J/kg·K. At 25 °C, 30 wt% hydrochloric acid has a density of about 1145.4 kg/m³, a dynamic viscosity of about 1.540 cP and a specific heat capacity of about 2177 J/kg·K. At 25 °C, 35 wt% hydrochloric acid has a density of about 1170.6 kg/m³, a dynamic viscosity of about 1.785 cP and a specific heat capacity of about 1856 J/kg·K.

Limitations

Before you use these numbers

▸Laliberte (2009) aqueous-electrolyte correlation for HCl-water. Tabulated for 5-35 wt% over 0-60 degC, within the well-characterised liquid region of the correlation. Concentrated hydrochloric acid is volatile and loses HCl to the vapour, more so when warm and concentrated, so closed handling is assumed. Values are for preliminary design; verify against vendor data for critical service.
▸Values are tabulated only inside the 5–35 wt% and 0–60 °C ranges shown; the correlation is not extrapolated beyond them here.
▸Figures are for a pure hydrochloric acid–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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