Weighing dish

In two separate weighing dishes, measure 10 g of sodium chloride (NaCl) and 10 g of sucrose... 

Using a weighing dish, measure 0.4-0.6 g of potassium hydrogen phthalate (KHP). Record the mass of KHP in Data Table 1. Transfer the KHP to a 250-mL Erlenmeyer flask. With a wash bottle filled with distilled water, rinse any residue from the weighing dish into the flask. 

Using a clean weighing dish, measure 0.3-0.4 g of the unknown acid into a 250-mL Erlenmeyer flask. Rinse any residue into the flask. Record the mass in Data Table 2. 

Jacque Stability Test. Jacque, director of the Spanish plant Cantabrica at Guldacano, near Bilbao, proposed a test for NC which was simple, rapid, and did not require complicated apparatus. It is not advisable to use this test when it is known in advance that the NC is of low stability Procedure. A NC sample of 2-3g, previously-dried in a loosely covered weighing dish or crystallizer to constant wt, is transferred to an oven maintained at 130—40° and left there for 2 hrs. It is cooled in a vacuum desiccator and reweighed. The sample is again heated at 140° and weighed at intervals of 2 hrs until it decomposes, as indicated by an abnormal loss of wt. After termination of the test, it is advisable to wash the NC with distilled water, add a few drops of 0. IN KMn04 soln and determine the amt of HN03, either by the nitron or diphenylamine method... 

Determination of Moisture. Transfer to a fared glass weighing dish a portion of approx 2 grams (g) of the sample and weigh accurately. Dry the dish and contents at 100°C to 105°C for 1 hr, cool in a desiccator and weigh. Calculate the loss in weight and percent of moisture... 

Weigh out 10.44 g of Bisphenol A epoxy resin into an aluminum weighing dish. 

Using another aluminum weighing dish, weigh out 2.06 g of diethylenetriamine. 

Add the diethylenetriamine to the aluminum weighing dish containing the Bisphenol A epoxy resin. 

Moisture. Weigh a 5g sample in a tared weighing dish provided with a stopper. Remove the stopper and heat the dish for 4 hrs at 40°. Replace the stopper, cool the dish and reweigh it... 

D) lnsolu.ble Material Retained on US Std No 40 Sieve. Treat a 100 g sample in a beaker with hot dist d w and pour the soln through the sieve. Transfer quantitatively any insol matter from the beaker to the sieve by means of a jet of hot distd w and when no more insol matter passes through the sieve, dry the sieve with residue at 100° for 1 hr. Transfer the dry residue to a piece of glazed paper and then to a tared weighing dish. Weigh the dish and calc the increase in wt as the %-age of in sol matter retained on the sieve (Ref 8,... 

Weighing dish (aluminum or glass) diameter 60 mm, depth 30 mm... 

Place the specimen in a tared stoppered weighing dish. 

Convection oven capable of maintaining a temperature of 103° 2°C Aluminum weighing dishes (with or without covers)... 

Dry an aluminum weighing dish (and cover, if used) >1 hr at 105°C. Cool and store dried dish in a desiccator. Cool >30 min before using. 

Covered weighing dishes are useful when analyzing samples that splatter. Weighing dishes without covers may otherwise be preferred, as they are disposable. 

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