Question

3.A pilot plant investigation is concerned with three variables. These are tempera- ture (160 ~ C and 170 ~ C), concentration of reactant (1.0 mol / L and 1.5 mol / L), and catalyst (Catalyst A and Catalyst B). The response variable is the percentage yield of the desired product. A factorial design will be used. a) If each combination of variables is tested twice (two replications), how many tests will be required? b) List them. c) How will the order of tests be determined?

Answer 1

a)

>> We have 3 variables and 2 factor levels for each varaibles

>> Number of test required is 2 x 2^3 = 16

>> the factors are

b)

60 ~ C , 1.0 mol / L , Catalyst A

60 ~ C , 1.0 mol / L , Catalyst B

60 ~ C , 1.5 mol / L , Catalyst A

60 ~ C , 1.5 mol / L , Catalyst B } two times

170 ~ C , 1.0 mol / L , Catalyst A

170 ~ C , 1.0 mol / L , Catalyst B

170 ~ C , 1.5 mol / L , Catalyst A

170 ~ C , 1.5 mol / L , Catalyst B

c) Order of the test is selceted at random without replacemnet from the the 8 test set decribed above