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The corrosion behavior and mechanism of mild steel/H₂SO₄ systems were examined using hydrogen gas evolution, HE, and weight loss, ML as chemical measurements, and electrochemical impedance spectroscopy, EIS, and potentiodynamic polarization, PDP as electrochemical measurements at 30^oC. From the chemical results, the corrosion rate of mild steel increased as well as increasing acid concentration, with a reaction constant of 0.70 and 0.60 for HE and WL, respectively. Different features including general and pitting corrosion can be shown on the mild steel surface after dipping in different concentrations of H₂SO₄, and the latter became more distinct at higher acid concentrations. EIS results showed that the R_p value decreases while the C_dl value increases along with increasing acid concentration. PDP results clearly revealed that the dissolution of mild steel undergoes anodic control. The chemical and electrochemical method suggested that the dissolution mechanism of mild steel is the same at different H₂SO₄ concentrations. Based on the results and observations, the mechanism of mild steel corrosion in H₂SO₄ can be explained based on the role of  anions, the main corrosive agent in aqueous  solutions, which partake directly in anodic dissolution and cathodic reaction during corrosion.