Table 6. EIS variables for mild steel dipped in 1 M HCl using varying amounts of DMF terpolymer.

Conc. (ppm)	R s (Ω cm2)	R ct (Ω cm2)	Y o (10−6 Ω−1 cm−2)	n	C dl (μF cm−2)	IE (%)
0	5.04	30.71	287.70	0.853	1377.18	—
20	5.07	144.75	192.30	0.88	776.35	43.63
40	5.14	190.23	145.84	0.896	478.19	65.28
60	5.20	214.20	126.90	0.902	384.80	72.06
80	5.39	273.34	76.78	0.911	202.99	85.26
100	5.85	337.66	42.20	0.935	82.05	94.04
120	6.31	382.663	36.10	0.937	68.53	95.02