For the standardization of their sodium hydroxide solution a pair of students weighed out 0.5342 g of KHP (MM 204.22 g/mol). They found that it took 21.36 mL of their NaOH solut…

Question

asked Sep 7, 2020 103k views

1 Answer

AlbertUI · Answer 1 · 2020-09-11T15:56:25+0000

Answer:

The concentration of their NaOH solution is 0.1225 M.

Step-by-step explanation:

Moles of KHP :

Given, Mass of KHP = 0.5342 g

Molar mass of KHP = 204.22 g/mol

The formula for the calculation of moles is shown below:

$moles = (Mass\ taken)/(Molar\ mass)$

Thus,

$Moles= (0.5342\ g)/(204.22\ g/mol)$

$Moles\= 2.6158* 10^(-3)\ mol$

According to the reaction shown below:

KHP + NaOH ⇒ KNaP + H₂O

1 mole of KHP reacts with 1 mole of NaOH

So,

$2.6158* 10^(-3)\ mol$ of KHP reacts with
$2.6158* 10^(-3)\ mol$ of NaOH

Moles of NaOH =
$2.6158* 10^(-3)\ mol$

Volume = 21.36 mL = 0.02136 L ( 1 mL = 0.001 L)

The expression for molarity is:-

$Molarity=(Moles\ of\ solute)/(Volume\ of\ the\ solution)$

Molarity_(NaOH)=(2.6158* 10^(-3))/(0.02136)

$Molarity_(NaOH)=0.1225\ M$

The concentration of their NaOH solution is 0.1225 M.