Question

A. Standardization of Sodium Hydroxide Solution Table 13.1 (data) Sample 1 Sample 2 Sample 3 Mass of container plus sample Mass of empty container Final buret reading 3.404g 3.4222g 3 104 and 3.070 4ml 15.80ml 18.50ml 0.00ml 0,80ml Risi Initial buret reading Table 13.2 (report) Molecular weight of KHP 204, 20 amal Sample 1 Sample 2 Sample 3 Mass of KHP titrated Moles of KHP titrated Moles of NaOH required in titration Volume of NaOH used in titration Calculated NaOH molarity Average NaOH molarity

table 13.2 help please!

Answer 1

The titration is used to obtain the concentration of a solution from the concentration of another known solution (standard solution). Thus, knowing the volume of both solutions (standard solution and problem solution) and the concentration of the standard solution, it is possible to know the concentration of the problem solution. In this case, sodium hydroxide is a difficult base to obtain in pure form because it tends to absorb water from the air and its solutions react with carbon dioxide. In this way, to know its concentration, it was titrated with potassium phthalate, which is an acid of known concentration. In this way the reaction that was carried out was a neutralization because an acid and a base reacted:

KHC₈H₄O₄ + NaOH $\rightarrow$ KNaC₈H₄O₄ + H₂O

acid base salt water

	Sample 1	Sample 2
Mass of KHP tritated	0.2991 g	0.4118 g
Moles of KHP titrated	0.00146 mol	0.00202 mol
Moles of NaOH required in titration	0.00146 mol	0.00202 mol
Volume of NaOH used in titration	15.80 mL	17.70 mL
Calculated NaOH molarity	0.0924 mol/L	0.1141 mol/L