877-24-7 potassium hydrogen phthalate

There are four major decomposition reactions that take place during the pyrolysis curve 1, water and phthalic anhydride volatize and a residue to dipotassium phthalate is formed. K2C8H404 curve 2, the latter compound decomposes to form potassium carbonate and carbonaceous material curve 3, the carbonaceous material loses mass slowly and finally burns giving a residue to K2C03 and curve 4, the potassium carbonate decomposes with the evolution of carbon dioxide, while the K20 formed reacts with the porcelain crucible sample holder. 

Newkirk and Laware (41) found that the initial isothermal rate of decom- 

300 C/h, under various conditions ----, air atmosphere, Pt crucible -, air atmosphere. 

Smalley et al. (60) proposed the use of potassium hydrogen phthalate as a TG standard. Using DTG, they observed six peaks in the curve when this compound was heated in air from 25-l000°C at a heating rate of 280°C/h. The peak minimum temperatures found were 300 10°. 400°, 5l0c, 565°, 680-700°, and 850°C, respectively. Since this compound is available in a high purity form as a pH standard, it is proposed for use as a TG standard as well. The peak temperatures are said to provide convenient reference points. 

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Lithium fluoride is the optimum crystal for all wavelengths less than 3 A. Pentaerythritol (PET) and potassium hydrogen phthalate (KAP) are usually the crystals of choice for wavelengths from 3 to 20 A. Two crystals suppress even-ordered reflections silicon (111) and calcium fluoride (111). 

In this experiment the overall variance for the analysis of potassium hydrogen phthalate (KHP) in a mixture of KHP and sucrose is partitioned into that due to sampling and that due to the analytical method (an acid-base titration). By having individuals analyze samples with different % w/w KHP, the relationship between sampling error and concentration of analyte can be explored. 

KHC3H4O4 is also known as potassium hydrogen phthalate, or KHP. 

When standardizing a solution of NaOH against potassium hydrogen phthalate (KHP), a variety of systematic and random errors are possible. Identify, with justification, whether the following are systematic or random sources of error, or if they have no effect. If the error is systematic, then indicate whether the experimentally determined molarity for NaOH will be too high or too low. The standardization reaction is... 

Potassium hydrogen phthalate [877-24-7] M 204.2. Crystd first from a dilute aqueous solution of K2CO3, then H20(3mL/g) between 100° and 0°. Before being used as a standard in volumetric analysis, analytical grade potassium hydrogen phthalate should be dried at 120° for 2h, then allowed to cool in a desiccator. 

Spray solution II Dissolve 92 mg potassium hydrogen phthalate in 100 ml water and adjust the pH to 5.0 with sodium hydroxide solution (1 mol/l). Dissolve 5 g sodium perchlorate in this solution [9]. 

Potassium hydrogen phthalate Sodium perchlorate monohydrate Sodium hydroxide solution (1 mol/l)... 

Potassium hydrogeniodate 262 Potassium hydrogen phthalate as pH standard, 569. 830... 

Nontoxic and noncorrosive solvent systems can be used when chitosan is considered instead of chitin for the manufacture of fibers. Improvements of the fiber quality rely mostly on technical shrewdness for instance the use of potassium hydrogen phthalate at pH 4-5 imparted better mechanical properties [255]. 

Cl K2Pt 16921-30-5) see Cisplatin potassium hydrogen phthalate (C H5K04 877-24-7) see Dolasetron mesilate potassium hydroxylamine-O-sulfonate (H2KNO4S 49J59-20- ) see Ibudilast potassium linolate... 

Spray solution II Dissolve 92 mg potassium hydrogen phthalate in 100 ml water... 

A titration requires a solution whose concentration is known. In Example the NaOH solution used as the titrant was known to be 0.1250 M. A titrant of known concentration is known as a standard solution, and the concentration of such a solution is determined by a standardization titration. In a standardization titration, the solution being titrated contains a known amount of acid or base. An excellent acid for standardization is potassium hydrogen phthalate, KHCg H4 O4. This substance, a carboxylic acid that contains one weakly acidic hydrogen atom per molecule, is easily obtained as a highly pure solid. A known number of moles can be weighed on an... 

A biochemist needed to standardize a solution of KOH. A sample of potassium hydrogen phthalate weighing 0.6745 g was dissolved in 100.0 mL of water and a drop of indicator was added. The solution was then titrated with the KOH solution. The titration required 41.75 mL of base to reach the stoichiometric point. Find the molarity of the KOH solution. 

C04-0031. To check the results of the first standardization, the biochemist repeated the titration. This time, a mass of 0.7015 g of potassium hydrogen phthalate dissolved in 135 mL of water required 43.36 mL of the base. Find the molarity and decide if the two results are consistent. 

C04-0141. A student prepared 1.00 L of a solution of NaOH for use in titrations. The solution was standardized by titrating a sample of potassium hydrogen phthalate whose mass was 0.7996 g. Before titration, the buret reading was 0.15 mL. When the indicator changed color, the buret reading was 43.75 mL. Calculate the molarity of the NaOH solution. 

C04-0157. As a final examination in the general chemistry laboratory, a student was asked to determine the mass of Ca (0H)2 that dissolves in 1.000 L water. Using a published procedure, the student did the following (1) About 1.5 mL of concentrated HCl (12 M) was added to 750 mL of distilled water. (2) A solution of KOH was prepared by adding approximately 1.37 g KOH to 1.0 L distilled water. (3) A sample of potassium hydrogen phthalate (185.9 mg) was dissolved in 100 mL of distilled water. Titration with the KOH solution required 25.67 mL to reach the stoichiometric point. (4) A 50.00-mL sample of the HCl solution prepared in step 1 was titrated with the KOH solution. The titration required 34.02 mL of titrant to reach the stoichiometric point. (5) The student was given a 25.00-mL sample of a saturated solution of Ca (0H)2 for analysis. Titration with the HCl solution required 29.28 mL to reach the stoichiometric point. How many grams of calcium hydroxide dissolve in 1.00 L of water ... 

Now the origin of the scale must be defined, i.e. a pH value must be selected for a standard (as close as possible to the value expected on the basis of definition 1.4.46). A solution of potassium hydrogen phthalate with a molality of 0.05 mol kg-1 has been selected as the reference value pH standard (RVS). 

The pH of the saturated solution of potassium hydrogen phthalate containing chloride molarity mcr is given by the equation... 

Table 3.7 Values of pH(RVS) for the reference value standard of 0.05 mol kg-1 potassium hydrogen phthalate at various temperatures... 

Mobile phase 0.001 mol dm-3 tetrabutyl ammonium hydroxide + potassium hydrogen phthalate, pH8. Flow rate 1 cm3 min 1... 

It takes 47.03mL of a base to titrate 2.000g of potassium hydrogen phthalate (KHC H404). What is the normality of the base ... 

Figure 42. Breakdown voltages for A1 anodized in (1) ammonium borate, (2) ammonium adipate, (3) potassium hydrogen phthalate, and (4) ammonium dihydrogen phosphate.285...

Merks and Vlasbom [114] carried out some comparative experiments on standard seawater with potassium hydrogen phthalate and water from Eastern Scheidt and Western Scheidt. These three types of samples were stored in three different ways and in three types of storage bottles. 

Standard solutions of potassium hydrogen phthalate, spiked with chloride, were also analysed. These results are compared with those given for the standard procedure in Table 11.4. 

Table 11.4. Analyses of chloride-spiked potassium hydrogen phthalate solutions by standard and sealed-tube procedures (1 ml 25% m/v silver nitrate solution) [200]... 

Step 2 Weigh out an appropriate amount of an acidic material, suitable for use as a primary standard, such as potassium hydrogen phthalate (KHP). 

Pure substance RMs pesticides with quoted purities, polycyclic aromatic hydrocarbons with quoted purities and potassium hydrogen phthalate with a quoted purity. 

You have been asked to prepare a 0.1 mol I-1 solution of potassium hydrogen phthalate (KHP) for use by colleagues in your laboratory. The solution must be properly labelled and the information you provide on the label must include the concentration of the solution together with a statement of its uncertainty at a 95% confidence level. 

Table 5.2 Acidic solvents. Reagents perchloric acid (acid) and potassium hydrogen phthalate (base).

The kinetics and mechanism of the ketone-bisulfite addition were studied by the use of the polarographic technique (Rao Salunke, Reaction Kinetics and Catalysis Letters 26 273, 1984).The specific rate was found to depend on pH. For an equimolar solution of bisulfite and acetone in a deaerated solution of potassium hydrogen phthalate buffer containing potassium iodide as the... 

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