Why is potassium hydrogen phthalate (KHP) (KHC8H4O4, MM= 204.227 g/mol) so widel

Question

Why is potassium hydrogen phthalate (KHP) (KHC8H4O4, MM= 204.227 g/mol) so widely used as a primary standard in acid-base titrations? Select all that apply.
php?id 4057476 Jump to... Why is potassium h ydrogen phthaiate (KHP) (KHCand·MM#204227 grmo) so weely used as a prn Due D ard in acid-base ttrations? Select all that apply It easily absorbs moisture from the atmosphere. R it is stable to air It is expensive. R it is available in high purity Late Of the choices listed to the left, three of hem are reasons that KHP is used. It is important that a primary standard is as possible Points P Grade Ca Descripts Polides It is an add-base indator It has a relatively high molar mass. Consider whether a high or low molar mass increases this accuracy. Also, select any option that ensures the sample remains pure phthalate (KHP) into a flask and adds water from she measure the volume of water with a more accurate device? The student 0.9361 g of potassium to dissolve t. Why You can c You can v grve up or You can ke until you g You lose 5s The volume of water added is not important because the ttration equivalence port depends only on the rumber of minoles of potassium acid phhaliate and not its concentration It would be better to measure the mass because t can be read to four decimal places with an analytical balance. The quantity of water actually is nt and should be O measured aiccurately because it aflects the starting concentration thus the starting pH of the solution two decimal places which is all the precision needed for a titration O eTextbook )(MM . 204 227 genol) regires 42.80 The titration of 0.9361 g of mL of NaOH solution. potassium hydrogen prthalate O Heljp with T

Explanation / Answer

KHP is available in the solid form and its molar mass is very high. Hence since moles= mass/molar mass. moles can be determined with precision. It does not pick moisture. it is availble in pure form. Is is stable in air as well. hence, 2,4 and 6 are correct.

2. moles of KHP= mass/molar mass =0.9361/ 204.227 =0.004584

the reaction of KHP with NaOH is

KHC8H4O4(aq) + NaOH(aq) --> KNaC8H4O4(aq) + H2O(l)

1 mole of KHP requires 1 mole of NaOH as per the stoichiometry of the reaction

hence 0.004584 moles of KHP requries 0.004584 moles of NaOH.

Molarity= moles/ Volume in L= 0.004584*1000/42.8   L=0.107M

Related Questions

Navigate

• Browse (All)
• Browse W
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.