Source

Sum of squares

df

Mean Square

F Value

p-value

Remarks

Model

2009.99

20

100.5

64.67

<0.0001

significant

X1-Leaching temp.

284.28

1

284.28

182.94

<0.0001

X2-Acid conc.

276.08

1

276.08

177.66

<0.0001

X3-S/L ratio

306.73

1

306.73

197.39

<0.0001

X4-Stirring rate

330.04

1

330.04

212.39

<0.0001

X5-Leaching time

278.80

1

278.80

179.41

<0.0001

X 4 X 5

9.61

1

9.61

6.18

<0.0302

X 1 2

146.26

1

146.26

94.12

<0.0001

X 2 2

147.90

1

147.26

95.18

<0.0001

X 3 2

125.75

1

125.75

80.92

<0.0001

X 4 2

149.55

1

149.55

96.24

<0.0001

X 5 2

112.45

1

112.45

72.36

<0.0001

Residual

17.09

11

1.55

Lack of fit

11.22

6

1.87

1.59

0.3132

not significant

Pure error

5.87

5

1.17

Cor total

2027.08

31