6C( graphite )+3H2( g)→C6H6(ℓ);ΔH=48.5 kJ/molC( graphite )+O2( g)→CO2( g);ΔH=−393.5 kJ/molH2(g)+21( g)⟶H2O(ℓ);ΔH=−286 kJ/mol equation −(1)×1+(2)×6+(3)×3−48.5−6×393.5−3×286=−3267.5 kJ for 1 mol=−6535 kJ for 2 mol Ans. 6535 kJ
Combustion of 1 mole of benzene is expressed at C6H6(l)+215O2( g)→6CO2( g)+3H2O(l). The standard enthalpy of combustion of 2 mol of benzene is −′x′kJ. x= ______ Given: 1. standard Enthalpy of formation of 1 mol of C6H6(l), for the reaction 6C (graphite) +3H2( g)→C6H6(l) is 48.5 kJ mol−1. 2. Standard Enthalpy of formation of 1 mol of CO2( g), for the reaction C (graphite) +O2( g)→CO2( g) is −393.5 kJ mol−1. 3. Standard and Enthalpy of formation of 1 mol of H2O(l), for the reaction H2( g)+21O2( g)→H2O(l) is −286 kJ mol−1.
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The wavelength of photon ' A ' is 400 nm. The frequency of photon ' B ' is $10^{16} \mathrm{~s}^{-1}$. The wave number of photon ' $C^{\prime}$ is $10^{4} \mathrm{~cm}^{-1}$. The correct order of energy of these photons is :
Given below are two statements: Statement I: The Henry's law constant $\mathrm{K}_{\mathrm{H}}$ is constant with respect to variations in solution's concentration over the range for which the solution is ideally dilute. Statement II: $\mathrm{K}_{\mathrm{H}}$ does not differ for the same solute in different solvents. In the light of the above statements, choose the correct answer from the options given below
For the reaction, $\mathrm{N}_{2} \mathrm{O}_{4} \rightleftharpoons 2 \mathrm{NO}_{2}$, graph is plotted as shown below. Identify correct statements. A. Standard free energy change for the reaction is $-5.40 \mathrm{~kJ} \mathrm{~mol}^{-1}$. B. As $\Delta \mathrm{G}^{\ominus}$ in graph is positive, $\mathrm{N}_{2} \mathrm{O}_{4}$ will not dissociate into $\mathrm{NO}_{2}$ at all. C. Reverse reaction will go to completion. D. When 1 mole of $\mathrm{N}_{2} \mathrm{O}_{4}$ changes into equilibrium mixture, value of $\Delta \mathrm{G}^{\ominus}=-0.84 \mathrm{~kJ} \mathrm{~mol}^{-1}$ E. When 2 mole of $\mathrm{NO}_{2}$ changes into equilibrium mixture, $\Delta \mathrm{G}^{\ominus}$ for equilibrium mixture is $-6.24 \mathrm{~kJ} \mathrm{~mol}^{-1}$.  Choose the correct answer from the options given below :
The half-life of ${ }^{65} \mathrm{Zn}$ is 245 days. After $x$ days, $75 \%$ of original activity remained. The value of $x$ in days is $\_\_\_\_$. (Nearest integer) (Given: $\log 3=0.4771$ and $\log 2=0.3010$)
One mole each of He and $A(g)$ are taken in a $10$ L closed flask and heated to $400$ K to establish the following equilibrium. $A(g) \rightleftharpoons B(g)$. $K_c$ for this reaction at $400$ K is $4.0$. The partial pressures (in atm) of He and $B(g)$ are respectively (at equilibrium) (Assume He, $A(g)$ and $B(g)$ behave as ideal gases) (Given: $R = 0.082$ L atm K$^{-1}$ mol$^{-1}$)
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