2.2. Weight Loss Measurements

For the weight loss measurements, the cleaned and weighed copper samples were immersed in 150 mL of the test solutions: 0.1 M HNO₃ solution without inhibitor (blank) and with different concentrations of the inhibitor, ranging from 10⁻⁴ to 10⁻⁶ M, at room temperature. After an exposure time of 48 h, the specimens were taken out, cleaned to remove the corrosion products, and weighed again. The weight loss was expressed in g m⁻² h⁻¹ by dividing by the total surface area of specimens and the exposure time. The inhibition efficiency (E) and surface coverage (θ) of MID were obtained using Equations (1) and (2):

where W_corr and W^o_corr represent the weight loss of the samples in the presence and absence of the inhibitor, respectively.