An aqueous solution containing 0.2 g of a non volatile solute ' $A$ ' in 21.5 g of water freezes at 272.814 K . If the freezing point of water is 273.16 K , the molar mass (in $\mathrm{g} \mathrm{mol}^{-1}$ ) of solute $A$ is $\left[\mathrm{K}_f\left(\mathrm{H}_2 \mathrm{O}\right)=1.86 \mathrm{~K} \mathrm{~kg} \mathrm{~mol}^{-1}\right]$
At $T(\mathrm{~K})$, the vapour pressure of $x$ molal aqueous solution containing a non-volatile solute is $12.078 \mathrm{kPa}_{\mathrm{d}}$, The vapour pressure of pure water at $T(\mathrm{~K})$ is 12.3 kPa . What is the value of $x$ ?
Consider the following cell reaction
$$ 2 \mathrm{Fe}^{3+}(a q)+2 \mathrm{I}^{-}(a q) \rightleftharpoons 2 \mathrm{Fe}^{2+}(a q)+\mathrm{I}_2(s) $$
At 298 K , the cell emf is 0.237 V . The equilibrium constant for the reaction is $10^x$. The value of $x$ is $\left(F=96500 \mathrm{C} \mathrm{mol}^{-1} ; R=8.3 \mathrm{JK}^{-1} \mathrm{~mol}^{-1}\right)$.
For a first order reaction, the ratio between the time taken to complete $\frac{3}{4}$ th of the reaction and time taken to complete half of the reaction is
AP EAPCET Papers
All year-wise previous year question papers