The point at which one drop of base turns the acid indicator into a pink color that lasts for thirty seconds in doing titration is called the end point or the equivalence point.
End point or the equivalence point is the one responsible for the pink color that lasts for thirty seconds.
Molality is defined as 1 mole of a solute in 1 kg of solvent.
Molality=

Number of moles of solute, n=

Given mass of the nitrobenzene=0.2 g
Molar mass of the substance= 123.06 g mol⁻¹
Number of moles of nitrobenzene,

Number of moles of nitrobenzene, n= 0.0016 mol
Mass of 10.9 g of naphthalene in kg=0.0109

Molality= 0.146 m
Answer:
Titration
Explanation:
The best technique which can be used to determine the number of moles of the HCl in the sample is titration.
The given amount of HCl solution must be titrated with known concentration of the base like NaOH.
The volume of NaOH required must be noted also.
According to the reaction,

At equivalence point
Moles of
= Moles of 
Considering:-
Moles of 
Thus, in this way, moles of HCl can be determined.