Vietnam or Thailand ? Vote for the TOP Country of the Week !
Updated: June 21, 2025
It is important, therefore, to take pains to use approximately the same volume of solution when standardizing that is likely to be employed in analysis; and when it is necessary, as is often the case, to titrate the solution at boiling temperature, the standardization should take place under the same conditions.
Add 10 cc. of dilute sulphuric acid and titrate to a faint pink with the permanganate solution, adding it directly to the contents of the vacuum flask. Should the end-point be overstepped, the ferrous sulphate solution may be added. From the volume of the solution required to oxidize the iron in the wire, calculate the relation to the normal of the permanganate solution.
Boil until the deep blue is displaced by a light bluish green coloration, or until brown stains form on the sides of the flask. Add a solution containing about 3 grams of potassium iodide, as in the standardization, and titrate with thiosulphate solution until the yellow of the liberated iodine is nearly discharged.
Add 1-2 cc. of freshly prepared starch solution and titrate to the disappearance of the blue color. As a strong acid it will also dissolve the copper from carbonate ores. The hydrochloric acid is added to dissolve oxides of iron and to precipitate silver and lead. The sulphuric acid displaces the other acids, leaving a solution containing sulphates only.
PROCEDURE. Weigh out into 500 cc. beakers two portions of about 0.150-0.175 gram of potassium bromate. Run in thiosulphate solution from a burette until the color of the liberated iodine is nearly destroyed, and then add 1 cc. or 2 cc. of starch solution, titrate to the disappearance of the iodo-starch blue, and finally add iodine solution until the color is just restored.
If too much chameleon has been added, one may titrate back with an accurately estimated solution of manganese, which is prepared most easily by evaporating fifteen cubic centimeters chameleon solution down to two or three cubic centimeters, boiling with two to three cubic centimeters hydrochloric acid so long as the smell of chlorine is observed, and then diluting the solution to ten cubic centimeters, when one cubic centimeter of it corresponds to the same measure of chameleon.
The solution of potato starch is less stable than the soluble starch. It is regarded as a "solid solution" of iodine in starch. Run out 40 cc. of the thiosulphate solution into a beaker, dilute with 150 cc. of water, add 1 cc. to 2 cc. of the soluble starch solution, and titrate with the iodine to the appearance of the blue of the iodo-starch.
On account of failure to boil out all the excess SO , 38.60 cubic centimeters of 0.1 N KMnO were required to titrate the solution. What was the error, percentage error, and what weight of sulphur dioxide was in the solution? From the following data, calculate the ratio of the nitric acid as an oxidizing agent to the tetroxalate solution as a reducing agent: 1 cc. HNO = 1.246 cc.
Word Of The Day
Others Looking