JEE Main 2021 — Redox Reactions Question with Solution
From: JEE Main 2021 (Online) 25th February Morning Shift
Question
0.4 g mixture of NaOH, Na2CO3 and some inert impurities was first titrated with HCl using phenolphthalein as an indicator, 17.5 mL of HCl was required at the end point. After this methyl orange was added and titrated. 1.5 mL of same HCl was required for the next end point. The weight percentage of Na2CO3 in the mixture is ________. (Rounded off to the nearest integer)
Enter your answer
Show full solutionCorrect answer: 3.975
Correct answer
3.975
Step-by-step explanation
1st end point reaction :
Eq of HCl used
2nd end point :
0.15 mmol =
= 3.975%
4%
Eq of HCl used
2nd end point :
0.15 mmol =
= 3.975%
4%
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