What will be the length of the gas column AB when the tube is held vertically with the end D up? — States of Matter and Gaseous State Chemistry Question

💡 Solution & Explanation

End D up: AB is bottom. Let AB length be $x$, CD is $80-x$. $P''_{AB} = 37.5(20/x) = 750/x$. $P''_{CD} = 37.5(60/(80-x)) = 2250/(80-x)$. Balance: $P''_{AB} = P''_{CD} + 20 \implies 750/x = 2250/(80-x) + 20$. Solving quadratic $2x^2 - 460x + 6000 = 0$ gives $x \approx 13.88 \text{ cm}$. Therefore, correct answer is D.