Whatman Grade 5 Qualitative Filter Paper is engineered for analytical applications requiring the utmost precision in fine particle retention. Manufactured under strictly controlled conditions from nearly 100% high-purity alpha-cellulose, this slow-flow filter paper delivers reliable, reproducible results for general laboratory filtrations, material identification, and clarification tasks.
With a particle retention rating of 2.5 us at 98% efficiency, this grade provides the maximum filtration capability within the qualitative range. It is the ideal choice for retaining fine precipitates in chemical analysis and effectively clarifying cloudy suspensions in environmental testing.
Grade: Grade 5
Particle Retention in Liquid: 2.5 um
Filtration Speed: Slow (Flow Rate: 250–300 seconds for 10ml distilled water)
Thickness: 0.19 mm
Basis Weight: 99 g/m2
Wet Burst Strength: 350 mm H2O
Ash Content: < 0.15% (via ignition at 900°C in air)
Package Includes: 3 packs of 100pcs (300pcs total)
Chemical Analysis: Efficiently traps and isolates fine crystalline precipitates.
Environmental Testing: Widely utilized for soil analysis and water quality clarification.
Vacuum Filtration: Exceptionally suited for standard Buchner funnel setups due to its high wet burst strength and stable structural composition.
[Maximum Fine Particle Retention] Features a precise 2.5 um pore size (at 98% efficiency), offering the highest degree of fine particle filtration in the qualitative paper range. Ideal for capturing minute precipitates and clarifying demanding solutions.
[High Purity & Low Ash Content] Manufactured from nearly 100% premium alpha-cellulose under rigorous quality control. The average ash content is kept under 0.15% (determined by ignition at 900°C), ensuring minimal interference with qualitative analyses.
[Optimized Slow Flow & Strength] Designed with a 250–300s flow rate (for 10ml distilled water) and a 0.19mm thickness. Boasts a robust wet burst strength of 350 mm H2O, maintaining structural integrity even when wet or under vacuum pressure.
[Versatile Laboratory Applications] Perfect for use in Buchner funnels, clarifying cloudy suspensions, environmental soil testing, water analysis, and recovering fine precipitates in chemical and industrial research.