Inhibitory Mechanism of Carbon Steel Corrosion in Sea Water by an Aqueous Extract of Henna Leaves

Table 3

Synergism parameter (𝑆_𝐼).

HE (mL)	𝜃1	Zn^2+; 25 (ppm) (𝜃2)	HE-Zn^2+; 𝜃^′1+2	𝑆𝐼	Zn^2+; 50 (ppm) (𝜃2)	HE-Zn^2+; 𝜃^′1+2	𝑆𝐼
2	0.28	0.16	0.41	1.0250	0.47	0.64	1.06
4	0.35	0.16	0.47	1.0301	0.47	0.76	1.4354
6	0.47	0.16	0.71	1.5351	0.47	0.88	2.3408
8	0.65	0.16	0.94	4.9	0.47	0.82	1.0305
10	0.47	0.16	0.64	1.2366	0.47	0.75	1.1236