Prepare the test solution by mixing one volume of Sp. Gr.0.90 Ammonium Hydroxide (NH4OH) with two volumes of distilled water and add Ammonium Chloride until solid crystals remain undisclosed at the bottom of the container.
Invert the reaction chamber set, remove the rubber cork 'F' and fill the reaction chamber 'D' with copper wire in spiral form replace the bung and return it in an upright position and connect with the burette tubing. Fill the reservoir and reaction chamber three quarter with fresh test solution with the leveling bottle 'B' held below the level of the burette, half fill the bottle with the test solution.
Draw the test solution from the reservoir in the reaction chamber by turning the burette stop cock 'H' to connect the burette with the reaction chamber and then lowering the leveling bottle. Squeeze the rubber pipe to expel all the air and then close the stop cock, so that reaction chamber and the inter-connecting rubber pipe are completely filled with test solution.
The purging vessel (lute) is half filled with water and the sample gas to be tested is allowed to bubble through water to atmosphere. Fill the burette with fresh solution by turning the stop cocks 'G' and 'H' to connect with the purging vessel, so that , all the air gets expelled. Repeat it till all the air bubbles are removed. When solution commences to flow from the burette to glass tube, close the stop cock 'G' close the cock it and replace the leveling bottle in the holder.