KHP a is good primary standard for several reasons. It's rather cheap, the purity level is high, it's water soluble, and best of all, it's chemically stable.
because it is solid and air-stable, making it easy to weigh accurately
KHP (potassium hydrogen phthalate) is available extremely pure (which is always good for a primary standard) and gives a very sharp end-point especially with Crystal Violet Indicator
It is a solution of known concentration. In acid base titrations we used KHP as the acid standard. We weighed it to 0.1 mg and made the solution up to a certain volume in a volumetric flask. We then standardized the base by titration. KHP was thus the primary standard and NaOH the secondary std.
Perchloric acid is a strong acid, whereas potassium hydrogen phthalate (KHP) is a weak acid. Therefore, perchloric acid will protonate KHP to form phthalic acid. In other words, even though both are considered acids, KHP is more basic than perchloric acid (when you compare their pKa or Ka, the true measure of acid strength). I'm not entirely sure what you mean by "standardized" however. Do you mean doing a titration? Often a solution of KHP is used to calibrate a pH meter because it's pH in solution is very stable. I would be surprised if a titration was done with perchloric acid and KHP however, but I'm not sure what else you could mean by asking why an acid is standardized using KHP. KHP is the primary standard used for the standarization of perchloric acid, usually 0.1M HCLO4 in concentration. It is the recommended primary standard in the pharmaceutical industry for analytical testing using perchloric acid for non-aqueous titration determinations. The protonation of KHP to phthalic acid when reacted with perchloric acid can be determined stoichiometrically. Using a dried KHP standard of known purity allows the determination of HCLO4.
The reasons KHP is used as a primary standard are as follows: (1) It is not hydroscopic, (2) it has a high molecular weight, so a reasonable amount to titrate can be easily weighed, and (3) it is stable at temperatures over 100°C so that any water may be driven off by heating.
Potassium acid phthalate is a common primary standard used to standardize bases. Obviously, it would depend upon how much NaCl was present, but the end result will be to reduce the amount of available H+ for the mass of KHP-NaCl mixture. That would cause you to understate the concentration of the base.
KHP (potassium hydrogen phthalate) is available extremely pure (which is always good for a primary standard) and gives a very sharp end-point especially with Crystal Violet Indicator
It is a solution of known concentration. In acid base titrations we used KHP as the acid standard. We weighed it to 0.1 mg and made the solution up to a certain volume in a volumetric flask. We then standardized the base by titration. KHP was thus the primary standard and NaOH the secondary std.
sodium hydroxide is a secondary standard because it absorb the moisture from the air and its concentration will change
Perchloric acid is a strong acid, whereas potassium hydrogen phthalate (KHP) is a weak acid. Therefore, perchloric acid will protonate KHP to form phthalic acid. In other words, even though both are considered acids, KHP is more basic than perchloric acid (when you compare their pKa or Ka, the true measure of acid strength). I'm not entirely sure what you mean by "standardized" however. Do you mean doing a titration? Often a solution of KHP is used to calibrate a pH meter because it's pH in solution is very stable. I would be surprised if a titration was done with perchloric acid and KHP however, but I'm not sure what else you could mean by asking why an acid is standardized using KHP. KHP is the primary standard used for the standarization of perchloric acid, usually 0.1M HCLO4 in concentration. It is the recommended primary standard in the pharmaceutical industry for analytical testing using perchloric acid for non-aqueous titration determinations. The protonation of KHP to phthalic acid when reacted with perchloric acid can be determined stoichiometrically. Using a dried KHP standard of known purity allows the determination of HCLO4.
The reasons KHP is used as a primary standard are as follows: (1) It is not hydroscopic, (2) it has a high molecular weight, so a reasonable amount to titrate can be easily weighed, and (3) it is stable at temperatures over 100°C so that any water may be driven off by heating.
Potassium acid phthalate is a common primary standard used to standardize bases. Obviously, it would depend upon how much NaCl was present, but the end result will be to reduce the amount of available H+ for the mass of KHP-NaCl mixture. That would cause you to understate the concentration of the base.
HCl is not used as a primary standard
HCl, hydrochloric acid, is the primary standard used to titrate against potassium hydroxide.
Either full synthetic or standard primary oil.
KHC8H4O4(aq) + NaOH(aq) --> KNaC8H4O4(aq) + H2O(l). The molar mass of KHP is approximately 204.22 g/mol. 1.54g of KHP is equivalent to 0.00754 mol of KHP. 1 mole of NaOH reacts per mole of KHP, so .00754 mol of NaOH are needed.
It is primary standard is a substance that has a known high digree of purity ,reatively large molar mass ,is nonhygroscopic and reacts in a predic table way.
Primary standard can be defined in metrology, as a standard that is accurate enough that it is not calibrated by or subordinate to the other standards. Primary standards are used to calibrate other standards.