[cuongt]

im going to do a prac on determing percentage of ammonia in cloudly ammonia.

can sum 1 help me explain wat i have to do in this prac.i.e method.

thanks  

[Borek]

What is cloudly ammonia?

Probably strong acid titration will be OK.

[cuongt]

can sum 1 check if my intro is ok?

Titration is a technique used to determine the amount (or concentration) of a given substance. A solution with a known volume and concentration is used to titrate (react with) another solution with a known volume and an unknown concentration. Some type of indicator is used to signal when all the unknown substance has been reacted. This is commonly called the end point of the titration.
The most common type of titration is one involving an acid and a base reacting with one another. In this practical cloudy ammonia and a solution of approximately 0.10molL-1 hydrochloric acid is provided. Hydrochloric acid needs to be standardized using sodium carbonate soln and can be used to determine the concentration of ammonia in the cloudy ammonia.
Na2CO3(aq) + HCl(aq) ---> 2NaCl(aq) + H2O + CO2
The unknown substance is household ammonia (a solution of ammonia, NH3). In order to determine the amount of ammonia in cloudy ammonia, it will need to be titrated with 0.10-molar hydrochloric acid (HCl).
HCl + NH3OH ---> NH3Cl+H2O
The end point of the titration can be seen by the first permanent color change. In this case it is yellow to orange.

[AWK]

HCl + NH3OH ---> NH3Cl+H2O

?!

HCl + NH4OH ---> NH4Cl+H2O

[cuongt]

isnt ammonia NH3 ammonium is NH4?

[Borek]

isnt ammonia NH3 ammonium is NH4?

Yes, but in water solution we assume ammonia reacts with water to produce NH₄OH:

NH₃ + H₂O -> NH₄OH

NH₄OH is a weak base and dissociaties

NH₄OH <-> NH₄⁺ + OH^-

The end point of the titration can be seen by the first permanent color change. In this case it is yellow to orange.

You have to name indicator used before you can say "in this case color changes from A to B".

[cuongt]

FULL THANKS BOREK u r so smart man  
i understand now