The Effect of the CO32- to Ca2+ Ion activity ratio on calcite precipitation kinetics and Sr2+partitioning

Table 2 Summary of calcite precipitation rates (R) as a function of ion activity ratio (aCO₃²^-/aCa²⁺) in this and previous studies

Ranges of aCO₃^2-/aCa²⁺	Ranges of R (mol m^-2 min^-1)	Ω (calc)	pH	Ionic Strength(M)	Electrolyte	References
0.048 - 39.34	3.84E-06 - 2.18E-05*	5.4 - 7.4	6.97 - 7.55	0.1 - 2.0	NaCl	Zhang&Dawe [26]
0.0002- 0.9997	5.17E-05 - 1.46E-04^±	5.3	7.21 - 9.01	0.1	KCl	Lin&Singer [27]
0.056 - 1.00	1.71E-04 - 2.21E-04^‡	1	8.50	0.018	NaCl	Tai et al.[28]
0.003 - 57	5.80E-05 - 8.87E-04**	5 - 19	10.2	0.1	NaCl	Nehrke et al. [20]
0.052 - 0.194	2.96E-06 - 2.7E-04^{± ±}	4.5 - 17.0	7.6 - 9.4	0.036	NH₄Cl	Tang et al. [21]
0.003 - 1.82	4.13E-05 - 8.47E-05	8.9 - 10.4	8.500	0.1	KCl	Current Study

*Values calculated based on data and equations given in table 1 of Zhang & Dawe [26]; ^± rate values used for calculation are estimated from Figure 6 in Lin & Singer [27]; ^‡rate values used for calculation are estimated from Figure 8 in Tai et al.[28], ** Values calculated based on data given in table 3 of Nehrke et al. [20], ^{± ±} Values calculated based on data and equations given in table 1 of Tang et al. [21]

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