2NaHCO3+H2C2O4⟶Na2C2O4+2CO2+2H2O Moles of CO2 evolved =25×1030.25=10−5 ∴∴ Mass of NaHCO3 Moles of NaHCO3=10−5=84×10−5 g=0.84×10−3 g=0.84mg ∴% by weight =×100=8.4%
JEE Main 2019 — Chemistry Physical Chemistry
A 10mg effervescent tablet containing sodium bicarbonate and oxalic acid releases 0.25 mL of CO2 at T=298.15 K and P=1 bar. If molar volume of CO2 is 25.0 L under such condition, what is the percentage of sodium bicarbonate in each tablet? [Molar mass of NaHCO3=84 g mol−1]
Held on 11 Jan 2019 · Verified 6 Jul 2026.
0.84
33.6
16.8
8.4
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