What is the PKA of Khp? What is the standardization of NaOH? Standardization is the process of determining the exact concentration molarity of a solution. What is the structure of Khp? Why is Khp dried before use? The potassium hydrogen phthalate KHP is a suitable primary standard because it is stable as a solid and in solution, it is soluble in water, it is not hygroscopic, it is easily dried and its molecular mass approximately g mol-1 results in convenient and accurately determined masses of the substance for making.
How does Khp titrate with NaOH? What is the purpose of standardizing the NaOH? Answer and Explanation: It is necessary to standardize a NaOH N a O H solution so as to know the exact concentration of a solution whose concentration is unknown.
What is equivalence point and endpoint? The equivalence point in a titration is the point at which the added titrant is chemically equivalent completely to the analyte in the sample. End point is the point where the indicator changes its color. In equivalence point the moles of acid are chemically equivalent to that of the moles of base.
Why is NaOH not used as a primary standard? However, the amount I added on an average was The theoretical value of the Sodium Hydroxide that was expected to be used was 9. However, there has been a deviation of 0. The resulting percentage error out of this deviation is:. Taking the value of 9. The percent error that has resulted in:. Another error was caused by the deviation in the mass of KHP. However, this, being only 0.
This means that due to systematic error, my accuracy has fallen by 9. The deviation in the volume, however, is not the only indicator of noticeable systematic errors. The volumes of NaOH used up show significant fluctuations. For example, in trial 1, I used The difference between these sets of data indicates that the systematic error of allowing the KHP solution to become too pale resulted in strange fluctuations.
These fluctuations caused the 0. The percentage uncertainty calculated of the concentration of NaOH was 2. Therefore, due to flaws in raw data values taken from systematic errors, there has been a deviation in uncertainty too, indicating the impact of methodical flaws.
The uncertainty of 2. Overall, the data obtained, although not completely inaccurate, have not been as accurate as it could have been. Upon completion of this lab, log onto OWL. A Lab Owl section should now appear in your courses and your first assignment, Lab Owl: Exp 2, should appear in this section. You have until the next scheduled laboratory to complete this assignment.
Three more assignments will appear here as the semester progresses. Stoichiometry and Solids. When dealing with solids that one can weigh on a balance, determining the number of moles in a particular sample is simply:. Mass in grams of the substance. Molar mass of the substance. Stoichiometry and Solutions. When dealing with solutions, one is usually concerned with concentration.
Concentration is not an unfamiliar term, in that in the geographical and political context the term "people concentration" is often used in allocating funds and describing population densities in various areas of the continent. While the number of people in two given regions may be the same, the area of the regions may be vastly different, and thus represent different concentrations.
In the chemical world concentration is usually expressed in terms of the quantity of a substance moles per liter of solution and is called Molarity M. Volume Liters of the solution. More often abbreviated to:. Determining the Molarity of a Sodium Hydroxide Solution. The reaction between an acid and base produces a salt and water, something that you may have heard before.
In the reaction that you will be investigating, the acid is potassium hydrogen phthalate KHP , and the base sodium hydroxide NaOH. As long as a reaction goes to completion, if one knows the following information:.
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