Home | | Chemistry 11th std | Estimation of halogens

Chapter: 11th Chemistry : Fundamentals of Organic Chemistry

Study Material, Lecturing Notes, Assignment, Reference, Wiki description explanation, brief detail

Estimation of halogens

A known mass of the substance is taken along with fuming HNO3 and AgNO3 is taken in a clean carius tube.

Estimation of halogens: 

carius method: 

A known mass of the organic compound is heated with fuming HNO3 and AgNO3. C,H &S get oxidized to CO2, H2O & SO2 and halogen combines with AgNO3 to form a precipitate of silver halide.


The ppt of AgX is filtered, washed, dried and weighed. From the mass of AgX and the mass of the organic compound taken, percentage of halogens are calculated.


A known mass of the substance is taken along with fuming HNO3 and AgNO3 is taken in a clean carius tube. The open end of the Carius tube is sealed and placed in a iron tube for 5 hours in the range at 530-540 k Then the tube is allowed to cool and a small hole is made in the tube to allow gases produced to escape. The tube is broken and the ppt is filtered, washed, dried and weighed. From the mass of AgX obtained, percentage of halogen in the organic compound is calculated.

Weight of the organic compound: w g

Weight of AgCl precipitate = a g

143.5 g of AgCl contains 35.5 g of Cl


Let Weight of silver Bromide be 'b'g

188g of AgBr contains 80 g of Br


 

EXAMPLE : 

0.284 g of an organic substance gave 0.287 g AgCl in a carius method for the estimation of halogen. Find the Percentage of Cl in the compound.

Weight of the organic substance = 0.284 g

Weight of AgCl is = 0.287 g

143.5 g of AgCl contains 35.5 g of chlorine


 

Study Material, Lecturing Notes, Assignment, Reference, Wiki description explanation, brief detail


Copyright © 2018-2020 BrainKart.com; All Rights Reserved. Developed by Therithal info, Chennai.