Table 9. Experimental Values of Solubilities and Dry Salt of the Quaternary System NaOH–Na₂SO₄–NaCl–H₂O at T = 363.15 K and P = 88.94 kPa^a.

	liquid mass %				dry salt (liquid) mass %
no.	NaOH	Na2SO4	NaCl	H2O	NaOH	Na2SO4	NaCl	H2O mass (g/100 g dry salt)	solution density ρ/g·cm–3	equilibrium phase solidsb
1	76.28	0.00	0.00	23.72	100.00	0.00	0.00	31.10	1.5884	OH
2	71.62	2.75	0.00	25.63	96.30	3.70	0.00	34.46	1.5884	S1 + OH
3	34.18	2.22	0.00	63.60	93.90	6.10	0.00	174.73	1.3321	S1 + S
4(E1)	41.85	3.13	0.71	54.31	91.59	6.86	1.55	118.87	1.4190	S + S1 + S3
5	49.07	3.64	2.65	44.64	88.63	6.58	4.79	80.59	1.5030	S + S3
6(E2)	60.44	3.42	4.60	31.54	88.28	5.00	6.72	46.07	1.5831	S + Cl + S3
7	64.73	3.27	3.98	28.02	89.92	4.55	5.53	38.92	1.5831	Cl + S3
8	74.98	2.91	3.12	18.99	92.56	3.59	3.85	23.44	1.5831	Cl + S3
9(E3)	81.28	2.58	2.33	13.81	94.30	2.99	2.71	16.03	1.5832	Cl + S3 + OH
10	79.13	4.58	1.31	14.98	93.07	5.39	1.54	17.62	1.5831	S1 + S3
11(E4)	78.12	3.70	1.07	17.11	94.25	4.46	1.29	20.65	1.5831	S1 + S3 + OH
12	68.87	0.00	2.87	28.26	96.00	0.00	4.00	39.39	1.5831	Cl + OH
13	27.34	3.97	15.75	52.94	58.09	8.44	33.47	112.50	1.3485	S + Cl
14	13.80	4.24	19.17	62.79	37.08	11.40	51.52	168.75	1.2496	S + Cl
15	0.00	5.71	25.75	68.54	0.00	18.15	81.85	217.86	1.1768	S + Cl
16	0.00	0.00	27.80	72.20	0.00	0.00	100.00	259.71	1.1723	Cl
17	0.00	29.91	0.00	70.09	0.00	100.00	0.00	234.34	1.1984	S

^aStandard uncertainties u are u(T) = 0.1 K, u(P) = 0.5 kPa, and u_r(Na₂SO₄) = u_r(NaCl) = u_r(NaOH) = 0.05.

^bAbbreviations: Cl, NaCl; OH, NaOH; S, Na₂SO₄; S1, Na₂SO₄·NaOH; and S3, Na₂SO₄·NaCl·NaOH.