Calculate the molarity of a sodium hydroxide solution if a 0.8316 g sample of KH

Question

Calculate the molarity of a sodium hydroxide solution if a 0.8316 g sample of KHP was dissolved in 50 mL of water and titrated with 24.71 mL of sodium hydroxide to a phenolphthalein endpoint. Use Equation (2), , and circle your final answer. Calculate the approximate volume (in mL) of a 6M NaOH solution required to prepare 500 mL of 0.12 M NaOH. (Show your work below, and circle your answer. This is the volume you will measure out at the start of the experiment. Transfer your calculations to the Calculations section of your lab notebook.)

Explanation / Answer

Q4)KHP is potassium hydrogen phthalate( a monobasic acid) with molar mass 204.22 g/mol

0.8316 g of KHP was dissolved in 50mLof water.

we know molarity = number of moles of solute / volume of solution in litres

Thus molarity of KHP is = (0.8316/204.22)x(1000/50)

= 0.0814

Now at equivalence the millimoles of acid = millimoles of base

That is (VN) acid = (VN) base

50mL x 0.0814 M = 24.71mL x M

Thus molarity of sodium hydoxide = 0.1648 M

Q5)molarity of stock solution =6M

volume of stock solution = ??

molarity of diluted solution = 0.12M

volume of diluted solution required = 500mL

on dilution the milliequivalents of solute remain the same that is

(VN)before dilution = (VN) after dilution

V x 6M = 500mL x 0.12M

The the volume of stock solution = 10 mL

Related Questions

Navigate

• Browse (All)
• Browse C
• Subjects

---

---

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