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प्रश्न
Calculate the mass of 1 cm3 of oxygen kept at STP.
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उत्तर
We know that 22.4 L of O2 contains 1 mol O2 at STP. Thus,
\[22.4 \times {10}^3 {\text { cm }}^3 \text {of O}_2 = 1 \text { mol O}_2 \]
\[1 {\text { cm }}^3 \text{ of O}_2 = \frac{1}{22.4 \times {10}^3} \text{ mol O}_2 \]
\[1 \text { mol of O}_2 = 32 \text { g }\]
\[\frac{1}{22.4 \times {10}^3}\text { mol of O}_2 = \frac{32}{22.4 \times {10}^3} = 1 . 43 \times {10}^{- 3} g\] \[= 1 . 43 \text{ mg }\]
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