The Development of a Mathematical Model for the Prediction of Corrosion Rate Behaviour for Mild Steel in 0.5 M Sulphuric Acid

Table 7

Analysis of variance (ANOVA) for corrosion rate in the presence of Grewia venusta extract.

Source of variation	Sum of squares	Degree of freedom (DF)	Mean square	𝐹cal= Ms/Error Ms	𝐹-value	𝐹 (%)
Main effect
𝐴	327.42	1	327.42	28.65	0.0332	7.48
𝐵	3209.61	1	3209.61	280.86	0.0035	73.28
𝐶	717.83	1	717.83	62.81	0.0155	16.39
Interaction
𝐴𝐵	50.50	1	50.50	4.42	0.1703	1.15
𝐵𝐶	51.51	1	51.51	4.51	0.1677	1.18
Residual	22.86	2	11.43			0.52
Cor. Total	4379.73	7				100