Whatman Grade 1 Qualitative Filter Papers are the most widely used filter paper for routine laboratory applications, qualitative analytical separations, and clarifying liquids. They are the standard grade cellulose filter papers for medium flow rates.Qualitative analytical separations for precipitates such as lead sulfate, calcium oxalate (hot), and calcium carbonateAgricultural soil analysis and seed testing proceduresIndustrial food processing techniques to extract liquid or separate solid foodstuffs from associated liquidAir pollution monitoring by collecting atmospheric dust from airflow and photometrically measuring the stain-intensityGas detection by quantitative chromogenesis with optical reflectanceMedium flow rate and retention for a wide range of qualitative analytical separationsGrade 1 Qualitative Filter Papers (11 µm particle retention) are available in a variety of sizes and formats including circles, sheets and prepleated filters. They are also available in FilterCup format, a convenient, 250 ml capacity disposable 70 mm filter funnel molded from polypropylene with an integral, heat-bonded filter.