What is the reaction behind the standardization of NaOH against Khp?
A commonly used primary standard for titration with sodium hydroxide solution is the weak acid potassium hydrogen phthalate or KHP (C8H5O4K). In this reaction as well, one mole of KHP completely reacts with one mole of NaOH. The titration of NaOH with KHP involves adding NaOH from the burette to a known volume of KHP.
What is the chemical reaction of KHP with NaOH?
We have a balanced chemical equation in which we now know the exact quantity of one of the reagents (KHP) – NaOH(aq) + KHC8H4O4(aq) = KNaC8H4O4(aq) + H2O(l) – thus we can determine the number of moles of NaOH that reacted with the KHP….Stoichiometry and Solutions.
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| V(L) |
What indicator is used for the standardization of NaOH?
phenolphthalein
We will standardize the ~0.1 M NaOH solution (the titrant) with potassium hydrogen phthalate (KHP, KC8H4O4H) using phenolphthalein as the indicator.
How do you standardize NaOH with KHP calculations?
To Standardize: Record the amount of KHP and water used. Add 4 drops of indicator into the flask and titrate to the first permanent appearance of pink. Near the endpoint, add the NaOH dropwise to determine the total volume most accurately.
Is KHP a primary standard?
Potassium Hydrogen Phthalate (KHP) is a classic primary standard substance in that it is readily available in high purity; is relatively inexpensive; is easy to dry; is neither hygroscopic, oxidized by air, nor affected by Carbon Dioxide (thus making it easy to weigh out); does not undergo decomposition during storage; …
Why is potassium hydrogen phthalate KHP used to standardize the NaOH which will be used during the experiment?
Potassium hydrogen phthalate, often called simply KHP, is an acidic salt compound. KHP is slightly acidic, and it is often used as a primary standard for acid–base titrations because it is solid and air-stable, making it easy to weigh accurately. It is not hygroscopic.
How do you use KHP to standardize NaOH?
To Standardize: Weigh ~0.8 g of dried KHP (MW = 204.23 g/mol) into an Erlenmeyer flask and dissolve in 50-75 mL of distilled water. Record the amount of KHP and water used. Add 4 drops of indicator into the flask and titrate to the first permanent appearance of pink.
Is potassium hydrogen phthalate a primary standard?
Potassium hydrogen phthalate is used as a primary standard for acid- base titrations as well as for calibrating pH meters. It acts as a buffer in pH determination.
How do you standardize chemicals?
Standardization is the process of determining the exact concentration (molarity) of a solution. Titration is one type of analytical procedure often used in standardization. In a titration, an exact volume of one substance is reacted with a known amount of another substance.
Why must a solution of NaOH be standardized using a primary standard such as KHP quizlet?
NaOH is hygroscopic, so it is not possible to weigh it accurately. KHP is hygroscopic, so it is not possible to weigh it accurately. NaOH is a primary standard, so a solution of it needs to be standardized. NaOH is hygroscopic, so it is not possible to weigh it accurately.