Assay Ammonium Chloride

Molecular formula: NH4Cl 

Molecular Weight: 53.5 

Assay: Weigh accurately about 0.1 g of ammonium chloride, dissolve it in 20 mL of water, and add a mixture of 5 mL of formaldehyde solution, previously neutralized to dilute phenolphthalein solution, and 20 mL of water. After 2 minutes, titrate slowly with 0.1 M sodium hydroxide using a further 0.2 mL of dilute phenolphthalein solution as an indicator. 


4NH4Cl + H2O → 4NH4OH + HCl 

4NH4OH + 6HCHO → (CH2)6N4 + 10H2O   

HCl + NaOH → NaCl + H2

Factor Calculation: 

1 Mole of NaOH ≅ 1 Mole of ammonium chloride 

1000 mL of 1M NaOH ≅ 53.5g of NH4Cl 

1 mL of 0.1 M NaOH ≅ 0.005349 g of NH4Cl

Make sure you also check our other amazing Article on : Acid Base Indicators
Sharing Is Caring:

Leave a Comment