Fig. 2. Effect of sample acidity on the extraction recovery of inorganic arsenic obtained from the proposed MAS-LIS-DLLME method. Extraction conditions: sample volume, 5 mL; concentration of inorganic arsenic, 2.0 ng mL⁻¹; amount of ascorbic acid, 100 μL of 10 mmol L⁻¹; extraction solvent volume, [C₆MIM][PF₆], 45 μL; dispersive solvent volume, methanol, 500 μL; amount of ammonium molybdate, 100 μL of 40 mmol L⁻¹; sample aspiration speed, 2200 step s⁻¹.