Crossword-Solution: TITRATION 9 letters, 1 clue 🏆 scrabble score: 9

This reaction proceeds according to the formula, 3MnCO_{3} + 2KMnO_{4} + H_{2}O = 2KHCO_{3} + 5MnO_{2} + CO_{2} and it may be employed for estimating the content of manganese by titration.

When manganese occurs along with iron, which in general is the case, we must take care that the iron in the solution is in the state of peroxide, which is precipitated on the addition of the bicarbonate of soda, and is allowed to remain as a precipitate, because it does not affect the titration injuriously.

Hence it thus follows that it ought to be arranged that a sufficient quantity of iron[1] (at least the same quantity as of manganese) be present in the liquid at titration, also that time be given for the precipitate to fall, so that the color of the solution may be observed between every addition of chameleon solution.

When the content of manganese is large the solution may be divided into two equal portions, one of which is first to be roughly titrated to ascertain its content approximately, after which the whole is to be mixed together and the titration completed, which can thus be performed with greater speed and certainty.

For the titration of iron with chameleon solution, the latter is commonly used of such a strength that 0.01 gramme of iron corresponds to about one cubic centimeter of chameleon solution, which is obtained by dissolving 5.75 grammes permanganate of potash in 1,000 cubic centimeters water.