Arsenic Removal from Natural Groundwater by Electrocoagulation Using Response Surface Methodology

Table 4

Analysis of variance (ANOVA) for the variables investigated during the As electroremoval process, fitted to a quadratic model.

Response variable	Source of variation	Sum of squares	Degrees of freedom	Mean squares	𝐹	𝑃
𝑈	Model (𝑄, 𝑖)	4.600	2	2.394	47.86	0.001
	Residual	0.250	5	0.050
	Interaction	0.222	1	0.212	4.44	0.089
	Total	5.072	8
𝑡	Model (𝑄, 𝑖)	23145.000	2	11345.80	33.76	0.001
	Residual	1680.000	5	336.00
	Interaction	2098.000	1	2097.60	6.24	0.055
	Total	26923.000	8
𝐸	Model (𝑄, 𝑖)	62612.700	2	32186.70	191.63	0.000
	Residual	839.800	5	168.00
	Interaction	1761.400	1	1761.40	10.49	0.023
	Total	65213.900	8