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Categories >> Sciences >> Chemistry >> Analytical Chemistry


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What is diffrence between residue on ignition and sulphated 
 Question Submitted By :: Analytical-Chemistry
I also faced this Question!!     Answer Posted By  
# 1
residue on ignition means the residue that left over on
ignition , the residue may be of any kind i.e sulphate, or
TiO2 or some other metal contamination.

Sulphated ash means the ash should be of the sulphate
Is This Answer Correct ?    123 Yes 18 No
# 2
Residue on Ignition is also known as total Ash.

Diluted sulphuric acid added to the total ash and again
ignited, the residue left behind is the sulphated ash.
Is This Answer Correct ?    57 Yes 16 No
Analytical Chemist
# 3
residue on ignition means sample is ignited at high
temperature and the remaining is the ash.
Sulphated ash means in the above ash add conc.sulphuric acid
and again ignite at high temperature.
Is This Answer Correct ?    28 Yes 6 No
# 4
Both are same
Residue on ignition as per USP
Sulphated ash as per EP
Is This Answer Correct ?    31 Yes 19 No
# 5
USP and Pheur (EP) have harmonized the methods. USP
accepts EP method as equivalent. Basically they are the
same tests.
Is This Answer Correct ?    18 Yes 14 No
# 6
In Residue of Ignition,the sample is ignited at high
temperatures as such,while in Sulphated Ash,sulphuric acid
is used before igniting the sample.
Is This Answer Correct ?    22 Yes 19 No
# 7
Residual on ignition mesure only present metal in inert
atm.not convert in oxide.
Residual on ignition mesure present of metal oxide in
normal atm.
Sulphated ash mesure only present of metal oxide. using
sulphuric acid.
Is This Answer Correct ?    3 Yes 0 No
Chandrakant Padodara
# 8
When a sample is ignited to ash as such this is called residue on ignition as the meaning itself tells us., while the sulphated ash is certain samples need to be charred with sulphuric acid before ignition and the residue contains sulphates which is called sulphated ash. Eventhough USP and BP says the samething this is product specific.

Thanks and regards
Is This Answer Correct ?    3 Yes 0 No
# 9
Residue on ignition means the sample is ignited at higher
temperature in the muffle furnace for the period of time.
If it is not converted as a complete ash(grey colour)add
dilute sulphuric acid to the residue and evaporate the
acidic solution again keep into the furnace to convert ash
is called sulphated ash.
Is This Answer Correct ?    3 Yes 1 No
# 10
sulphated ash is the ash of sulphates & residue on
ignition is the residue of sulphates,oxides and TiO2
content or some other heavy metals.
Is This Answer Correct ?    1 Yes 0 No
Ravindra Surdikar

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