Preparation of 1N hydrochloric acid (HCl)

Overview

  • HCl is supplied as 36 -38% (w/w) concentrated liquid form.
  • The normality of a 37% HCl solution  (average conc.) which has density 1.2 g/ml, is 12.18 N.

Requirements

  • Reagents
    • 37% (w/w) stock solution of HCl
    • Deionized/Double distilled water
  • Equipment and disposables
    • Measuring cylinder
    • Beaker
Objective:

Preparation of 100 ml of 1N HCl solution from stock solution of HCl [37% (w/w)]

Procedure:

Step 1: Calculate the volume of conc. stock solution required to prepare 1N HCl solution

Use formula: Cf * Vf = CS * VS

Cf: Concentration of final solution = 1 N
Vf: Volume of the final solution = 100 ml
CS: Concentration of stock solution = 12.18 N

VS: Amount stock solution required i.e., Unknown

                               1 X 100 = 12.178 X VS           OR

                               VS = 1 X 100 / 12.18      =    8.2 ml

                              Amount of water = 100 – 8.2 = 91.8 ml

Step 2:  Take 91.8 ml water in a measuring cylinder and add 8.2 ml concentrated HCl. Mix. Transfer solution to a appropriate glass bottle.

Storage: Solution can be stored at room temperature for several months.

Application: 1N HCl can be used for pH adjustment.