Moles of removed CO2=6.02×10231021 mol =1.66×10−3 mol mole of CO2 left =2.8×10−3moles total moles of CO2 taken initially =(2.8+1.66)×10−3 mol mass of CO2 taken initially $\begin{aligned}
& =4.46 \times 10^{-3} \times 44 \
& =196.24 \times 10^{-3} \mathrm{~g} \
& =196.24 \mathrm{mg}
\end{aligned}$
2.8 × 10^-3 ~mol of CO_2 is left after removing 10^21 molecules from its ' x ' mg sample. The mass of CO_2 taken initially is Given: N_ A=6.02 ×…
JEE Main 2025 — Chemistry Physical Chemistry
2025mcqeasy
2.8×10−3 mol of CO2 is left after removing 1021 molecules from its ' x ' mg sample. The mass of CO2 taken initially is Given: NA=6.02×1023 mol−1
Official previous-year question
Held on 23 Jan 2025 · Verified 6 Jul 2026.
Options
- A
98 .3 mg
- B
48.2 mg
- C
196 .2 mg
- D
150 .4 mg
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