For the fuel cell reaction:
$2H_{2(g)} + O_{2(g)} \to 2H_2O_{(l)}$; $\Delta_fH^o_{298}(H_2O_{(l)}) = -285.5 \ kJ/mol$
What is $\Delta S^o_{298}$ for the given fuel cell reaction?
Given: $O_{2(g)} + 4H^+_{(aq)} + 4e^- \to 2H_2O_{(l)}$; $E^o = 1.23 \ V$

The molar conductivity of acetic acid solution at infinite dilution is $390 \ S \ cm^2 \ mol^{-1}$. What is the molar conductivity of $0.01 \ M$ acetic acid solution (in $S \ cm^2 \ mol^{-1}$)? (Given: $K_{a}(CH_3COOH) = 1.8 \times 10^{-5}$,assume $1-\alpha \approx 1$)

Calculate the equilibrium constant at $298 \ K$ for the following reaction and also calculate the maximum work that can be obtained from this cell:
$Mg(s) \ | \ Mg^{2+}(aq) \ || \ Ag^{+}(aq) \ | \ Ag(s)$
Given: $E_{Mg^{2+} \mid Mg}^{o} = -2.37 \ V$ and $E_{Ag^{+} \mid Ag}^{o} = 0.80 \ V$

$1000 \, mL$ of $1 \, M$ $CuSO_{4(aq)}$ is electrolysed by $9.65 \, A$ current for $100 \, s$ using $Pt$ electrodes. Which statement is incorrect?

Chemical reactions involve the interaction of atoms and molecules. $A$ large number of atoms/molecules (approximately $6.023 \times 10^{23}$) are present in a few grams of any chemical compound,varying with their atomic/molecular masses. To handle such large numbers conveniently,the mole concept was introduced. This concept has implications in diverse areas such as analytical chemistry,biochemistry,electrochemistry,and radiochemistry. The following example illustrates a typical case involving a chemical/electrochemical reaction,which requires a clear understanding of the mole concept. $A$ $4.0 \ M$ aqueous solution of $NaCl$ is prepared and $500 \ mL$ of this solution is electrolysed. This leads to the evolution of chlorine gas at one of the electrodes (atomic mass: $Na=23, Hg=200; 1 \ F = 96500 \ C$).
$1.$ The total number of moles of chlorine gas evolved is:
$(A)$ $0.5$ $(B)$ $1.0$ $(C)$ $2.0$ $(D)$ $3.0$
$2.$ If the cathode is a $Hg$ electrode,the maximum weight $(g)$ of amalgam formed from this solution is:
$(A)$ $200$ $(B)$ $225$ $(C)$ $400$ $(D)$ $446$
$3.$ The total charge (coulombs) required for complete electrolysis is:
$(A)$ $24125$ $(B)$ $48250$ $(C)$ $96500$ $(D)$ $193000$

For lead storage battery,pick the correct statements:
$A.$ During charging of battery,$PbSO_4$ on anode is converted into $Pb$.
$B.$ During charging of battery,$PbSO_4$ on cathode is converted into $PbO_2$.
$C.$ Lead storage battery consists of a grid of lead packed with $PbO_2$ as cathode.
$D.$ Lead storage battery has $\sim 38\%$ solution of sulphuric acid as an electrolyte.
Choose the correct answer from the options given below: