The inhibition of Tw-80 (Tween-80) to carbon steel in sulfuric acid was studied by potential scan and AC impedance techniques. The results indicated that,in 10% sulfuric acid,Tw-80 led to the passivation of carbon steel. When the concentration of Tw-80 was 47.52 mg/L, it provided the best inhibition ability for carbon steel, which is an a...