The phthalein formed from gallic acid and phthalic anhydride really results from the union of the latter with pyrogallol.
The phthalein itself is a yellow dye, and the solutions of its salts show a splendid and most intense greenish yellow fluorescence, for which reason it is called "fluorescein.
The dye introduced by Caro in 1874 is the brominated phthaleinof resorcinol.
Phenol-phthalein solution being added, the excess of potash is estimated by carefully titrating with standard hydrochloric acid solution.
After cooling, the liquid is titrated with N/2 aqueous KOH solution, using phenol-phthalein as indicator, this figure giving the amount of the total fatty acids present.
Add a drop of phenol- phthalein solution and titrate, with a half normal solution of sodium hydrate (use a 100 c.
A tenth normal solution of sodium hydroxide (NaOH), with phenol-phthalein as indicator, will be found the most convenient method of determining the total acid present.
Erlenmeyer flask, and add a little of the phenol-phthalein solution, and titrate with the tenth normal soda solution.
The phthalein on the day following the second venesection was 45 per cent in two hours.
The phthalein excretion is normal or only slightly reduced.
The phthalein elimination was 65 per cent in two hours.
As the case advances the phthalein output becomes less and less, until a period is reached when there are only traces or complete suppression at the end of a two-hour period.
The phthalein excretion is quite normal and the excretions of salt and nitrogen are also normal.
The above list will hopefully give you a few useful examples demonstrating the appropriate usage of "phthalein" in a variety of sentences. We hope that you will now be able to make sentences using this word.
