английский => русский Наука Химия; химические науки и технологии

Контроль качества. Определение процента нерастворимых веществ в порошке.
Pour 200 ml of water in a 400 ml beaker at room temperature. Add 1 g of powder while stirring on a magnetic stirrer. Pour the dissolved sample into the filter funnel, and drain. After the filter funnel is completely drained, rinse the filter funnel under a gentle stream of cold running tap water (avoid high pressure water) until the filtrate is free of polymer.

Count the number of points remaining on the screen and report the percentage as determined below: If there are less than 30 points, the insoluble percentage is estimated to be less than 1 %. If the screen is covered and the solution has filtered, the insoluble percentage is estimated to be less than 2%.