Question

Potassium tydrogen phthalate is a solid, monoprotic acid frequently used in the labonatory as a primary standard.It has the horthand notation as KHP unwieldy formula of KHC, H,04 This is often written in are needed to neutralize 1.50 grams of KHP, what is the molarity of the sodium hydroxide solution?

Answer 1

Ans. Given-

Mass of KHP = 1.50 g

Known, Molar mass of KHP = 204.22 g mol^-1

Now,

Moles of KHP = Mass / Molar mass = 1.50 g / (204.22 g/mol) = 0.007345 mol

# Balanced Reaction of neutralization:     

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

According to the stoichiometry of balanced reaction, 1 mol NaOH neutralizes 1 mol KHP.

So,

            Moles of NaOH consumed = Moles of KHP neutralized

            Hence, Moles of NaOH consumed = 0.007345 mol

Now,

Molality of NaOH solution = Moles of NaOH / Volume of solution in liters

                                                = 0.007345 mol / 0.0268 L

                                                = 0.2741 mol/ L

                                                = 0.2741 M

Therefore, molarity of NaOH solution = 0.2741 M