Table 4. Experimental Data Corresponding to the Invariant Points of the Binary and Ternary Subsystems in the Quaternary System Li⁺, Rb⁺, Mg²⁺//SO₄^2––H₂O at T = 273.2 K and Pressure P = 94.77 kPa^a.

no.	system	composition of solution, w(B) × 102				Jänecke index of dry salt				equilibrated solid phase
						J(Li2SO4) + J(Rb2SO4) + J(MgSO4) = 100
		w(Li2SO4)	w(Rb2SO4)	w(MgSO4)	w(H2O)	J(Li2SO4)	J(Rb2SO4)	J(MgSO4)	J(H2O)
a	Li+//SO42––H2O	26.88	0.00	0.00	73.12	100.00	0.00	0.00	284.62	LSH
b	Rb+//SO42––H2O	0.00	27.27	0.00	72.73	0.00	100.00	0.00	266.70	RS
c	Mg2+//SO42––H2O	0.00	0.00	21.03	78.97	0.00	0.00	100.00	375.51	MSH
A	Li+, Rb+//SO42––H2O	23.06	1.36	0.00	75.58	94.43	5.57	0.00	309.50	LSH + LRH
B		17.72	11.94	0.00	70.34	71.67	28.33	0.00	237.15	LRH + LR
C		9.67	24.67	0.00	65.66	28.16	71.84	0.00	191.21	LR + RS
D	Li+, Mg2+//SO42––H2O	19.38	0.00	10.81	69.81	64.49	0.00	35.81	231.24	LSH + M7
E	Rb+, Mg2+//SO42––H2O	0.00	2.47	20.56	76.97	0.00	10.73	89.27	334.22	RMH + M7
F		0.00	26.92	0.23	72.85	0.00	99.15	0.85	268.32	M7 + RS
E1	LLi+, Rb+, Mg2+//SO42––H2O	18.60	1.06	11.50	68.85	59.70	3.39	36.91	220.99	LRH + LSH + M7
E2		13.92	2.30	14.81	68.97	44.87	7.40	47.73	222.22	LRH + LR + M7
E3		8.93	2.69	16.96	71.42	31.24	9.43	59.34	249.87	LR + RMH + M7
E4		10.93	18.43	0.46	70.19	36.64	61.82	1.54	235.40	RMH + LR + RS

^aw(M) is the mass fraction of M; standard uncertainties u are u(T) = 0.20 K; u(Li⁺) = 0.005; u(Rb⁺) = 0.0061; u(Mg²⁺) = 0.005; u(SO₄^2–) = 0.0060; LRH: 3Li₂SO₄·Rb₂SO₄·2H₂O; RMH: Rb₂SO₄·MgSO₄·6H₂O; LR: Li₂SO₄·Rb₂SO₄; M₇: MgSO₄·7H₂O; LSH: Li₂SO₄·H₂O; and RS: Rb₂SO₄.