【讨论】Fluosilicate氟矽化物

Fluosilicate氟矽化物 检测方法
Dissolve 2.0g in 40 ml of water in a platinum dish, add 10 ml of a saturated solution of potassium nitrate, cool the solution to 0℃, and add 3 drops of phenolphthalein TS. If no color appears, a pink color persisting for 15s is produced by not more than 2.0 ml of 0.10N sodium hydroxide. If the solution is colored pink by the addition of phenolphthalein TS, it is rendered colorless by not more than 0.50 ml of 0.10N sulfuric acid. Save the neutralized solution fro the test for fluosilicate.

After the solution from the test before has been neutralized, heat to boiling, and titrate while hot with 0.10N sodium hydroxide until a permanent pink color is obtained: not more than 1.5ml of 0.10 N sodium hydroxide is required.