Stopper, removing from bottle

Therefore, concentrated H SO should always be diluted by adding it tc water, never the reverse. Remove stopper from the bottle in FIGURE 39.1, pour the diluted H2SO4 into the beetle, and immediately replace the stopper. 

Sampling. Using a rubber dipper, a sample of approx 2 oz shall be removed from each lot and transferred to a rubber bottle with a rubber stopper. The bottle shall be labeled to show source of manuf, plant, contract or purchase order No, lot No and number of pounds... 

Suspended solids are removed from the other aliquot of the sample as follows. Add 1 mL of 6 A NaOH to a 500-mL glass bottle. Fill the bottle with the sample. Add 1 mL of A1C13 solution (10 g A1C13 6 H20 in 15 mL water). Stopper the bottle. Rotate the bottle back and forth for 2 min to flocculate the contents. Allow the contents to settle for 10 to 15 min Draw out the supernatant liquid to analyze sulfide. The difference in the sulfide values obtained from both the tests (i.e., before and after removing suspended solids from the sample), is equal to the concentration of dissolved sulfide. 

Store the solution in a stoppered glass bottle away from light. Pour a small volume of TC-1 into the tray or vessel to be cleaned. Slosh it around so that the solution has access to all parts of the tray then pour the solution out and wash the tray thoroughly with water until all traces of the cleaner disappear. This solution will remove stains caused by oxidation products of developers as well as some silver and dye stains. It should not be used to clean hands. 

Assay Transfer about 1 g of sample, accurately weighed, into a suitable pressure bottle add 25.0 mL of 1 A potassium hydroxide and 15 mL of isopropanol stopper the bottle and wrap securely in a canvas bag. Place in a waterbath maintained at 98° 2°, and heat for 1 h, allowing the water in the bath to just cover the liquid in the bottle. Remove the bottle from the bath, cool in air to room temperature, then loosen the wrapper, uncap the bottle to release any pressure, and remove the wrapper. Add 6 to 8 drops of phenolphthalein TS, and titrate the excess alkali with 0.5 N sulfuric acid just to the disappearance of the pink color. Perform a blank determination (see General Provisions), and make any necessary correction. Each milliliter of 0.5 N sulfuric acid is equivalent to 36.37 mg of C9H14O6. 

To transfer a chemical from a bottle to a small jar or beaker, remove the stopper from the bottle, tip the bottle and rotate it over the desired container until the proper amount is in the new container. 

Remove the stopper from a bottle of strong nitric acid. Is it very hygroscopic What other acid acts similarly ... 

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