Acid solubility determinations.
Write this paragraph in past tense: Read the temperature of one of the solutions to 0.1°C Immediately
after that withdraw 10 cm³ sample from it using preheated to 60°C piperte', and discharge it into a
tarred 100 cm³ conical flask Weigh the flask again To avoid withdrawing small crystals of acid that have
separated from the maternal solution on cooling, attach a small piece of plastic rubing packed with dry
cotton wool to the pipette Remove this endpiece filter before discharging the solution into the flask 4
Dilute the solution to 50 cm with water Add two to Sve drops of the phenolphthalein indicator and
titrate against 0 10 M sodium hydroxide 5. Make similar determination of the solubility for the
remaining samples, duplicate at each of the specified above temperatures
The temperature of one of the solutions was read to 0.1°C. Immediately after that, a 10 cm³
sample was withdrawn from it using a preheated to 60°C pipette and discharged into a tarred 100
cm³ conical flask. The flask was weighed again. To avoid withdrawing small crystals of acid that
had separated from the maternal solution on cooling, a small piece of plastic rubbing packed with
dry cotton wool was attached to the pipette. This endpiece filter was removed before discharging
the solution into the flask.
The solution was diluted to 50 cm with water. Two to five drops of the phenolphthalein indicator
were added, and it was titrated against 0.10 M sodium hydroxide.
Similar determinations of the solubility were made for the remaining samples, duplicates at each
of the specified above temperatures.