Vietnam or Thailand ? Vote for the TOP Country of the Week !
Updated: June 5, 2025
PROCEDURE. Rinse a previously calibrated burette three times with the hydrochloric acid solution, using 10 cc. each time, and allowing the liquid to run out through the tip to displace all water and air from that part of the burette. Then fill the burette with the acid solution. Carry out the same procedure with a second burette, using the sodium hydroxide solution.
If the flocculent character was occasioned by the presence of magnesium hydroxide, the second precipitation, in a smaller volume containing fewer salts, will often result more favorably. !Absorption Apparatus!
When first precipitated the hydroxides are all readily soluble in acids, but aluminium hydroxide dissolves with considerable difficulty after standing or boiling for some time.
Then add sodium hydroxide solution until the precipitate which first forms is redissolved and a clear blue liquid obtained. Heat the upper portion of the liquid slowly to near the boiling point. A little below the boiling point the blue color disappears and a yellow-red precipitate is formed.
The heat from the burner is thus reflected into the crucible and dries the precipitate without danger of loss as the result of a sudden generation of steam within the mass of ferric hydroxide.
The volume thus calculated will be in excess of that actually required for precipitation, since the acids are in part consumed in the oxidation process, or are volatilized. Heat the solution to boiling, and allow the precipitated ferric hydroxide to settle. Wash twice by decantation with 100 cc. of hot water. Reserve the filtrate.
Word Of The Day
Others Looking