NTA JEE Mains 24th Jan 2025 Shift 1

$$ X\,g $$ of benzoic acid on reaction with aq. $$NaHCO_3$$ released $$CO_2$$ that occupied $$11.2\,L$$  volume at STP.  $$X$$  is  $$\underline{\hspace{2cm}}\,g. $$

Consider the following reaction occurring in the blast furnace: $$Fe_3O_4(s) + 4CO(g) \rightarrow 3Fe(l) + 4CO_2(g) x$$ kg of iron is produced when  $$2.32\times10^3\,kg\,Fe_3O_4$$ and $$2.8\times10^2\,kg\,CO$$ are brought together in the furnace. The value of  $$x$$  is  $$\underline{\hspace{2cm}}$$ (nearest integer). Given: $$M(Fe_3O_4)=232\,g\,mol^{-1},$$ molar mass of  $$CO=28\,g\,mol^{-1},$$ molar mass of $$(Fe)=56\,g\,mol^{-1}.$$

$$ 37.8\,g\,N_2O_5$$ was taken in a  $$1\,L$$ reaction vessel and allowed to undergo the following reaction at 500 K  $$2N_2O_5(g) \rightleftharpoons 2N_2O_4(g) + O_2(g)$$ The total pressure at equilibrium was found to be  $$18.65\,$$bar.  Then, $$K_p = \underline{\hspace{2cm}}\times10^{-2}$$  [nearest integer]. Assume  $$N_2O_5$$  to behave ideally under these conditions. Given:  $$R=0.082\,bar\,L\,mol^{-1}K^{-1}$$

Among the following cations, the number of cations which will give  characteristic precipitate in their identification tests with $$K_4[Fe(CN)_6]$$  is  $$\underline{\hspace{2cm}}$$. $$Cu^{2+},\; Fe^{3+},\; Ba^{2+},\; Ca^{2+},\; NH_4^{+},\; Mg^{2+},\; Zn^{2+}$$

Standard entropies of  $$X_2,\ Y_2$$  and  $$XY_5$$  are  $$70,\ 50$$  and  $$110\,J\,K^{-1}mol^{-1}$$ respectively. The temperature in Kelvin at which the reaction $$\frac{1}{2}X_2 + \frac{5}{2}Y_2 \rightleftharpoons XY_5 \Delta H^\ominus = -35\,kJ\,mol^{-1}$$ will be at equilibrium is $$\underline{\hspace{2cm}}$$  (Nearest integer).}