i did the same experiment but i used HCl and NaOH to get basic and acidic solutions
we had 3 test tubes (2 for repetition, 1 for control) for each pH value (which were 0.7, 2, 4 ,7 and 10)
we added catalase in the form of potato puree and we added 10 ml of HCl or NaOH (or distilled water for...