JEE Main & Advanced
Sample Paper
JEE Main - Mock Test - 37
question_answer
\[0.5g\]of fuming sulphuric acid \[({{H}_{2}}S{{O}_{4}}+S{{O}_{3}}),\]called oleum, is diluted with water. This solution completely neutralised by \[26.7mL\] of \[0.4\text{ }M\]\[NaOH\]. The percentage of free \[S{{O}_{3}}\] in the sample solution is ______.