JEE MainsJEE AdvanceBITSAT

JEE Mains | PYQ

At \( 25^{\circ}\mathrm{C} \) and \( 1 \, \text{atm} \) pressure, the enthalpy of combustion of benzene \( (l) \) and acetylene \( (g) \) are \( -3268 \, \mathrm{kJ \, mol^{-1}} \) and \( -1300 \, \mathrm{kJ \, mol^{-1}} \), respectively. The change in enthalpy for the reaction \( 3\mathrm{C_2H_2} \, (g) \rightarrow \mathrm{C_6H_6} \, (l) \).

For combustion of one mole of magnesium in an open container at $300\text{ K}$ and $1\text{ bar}$ pressure, $\Delta_{\text{C}}\text{H}^{\ominus} = -601.70\text{ kJ mol}^{-1}$, the magnitude of change in internal energy for the reaction is __________ $\text{kJ}$.

(Nearest integer)

(Given : $\text{R} = 8.3\text{ J K}^{-1}\text{ mol}^{-1}$)

\( 17.0 \, \text{g} \) of \( \text{NH}_3 \) completely vapourises at \( -33.42^\circ \text{C} \) and \( 1 \, \text{bar} \) pressure and the enthalpy change in the process is \( 23.4 \, \text{kJ mol}^{-1} \). The enthalpy change for the vapourisation of \( 85 \, \text{g} \) of \( \text{NH}_3 \) under the same conditions is ________ \( \text{kJ} \).

\( 40\% \) of \( \text{HI} \) undergoes decomposition to \( \text{H}_2 \) and \( \text{I}_2 \) at \( 300 \, \text{K} \). \( \Delta G^\ominus \) for this decomposition reaction at one atmosphere pressure is ________ \( \text{J mol}^{-1} \). [Nearest integer] (Use \( R = 8.31 \, \text{J K}^{-1} \text{mol}^{-1} \); \( \log 2 = 0.3010 \), \( \ln 10 = 2.3 \), \( \log 3 = 0.477 \))

A fish swimming in water body when taken out from the water body is covered with a film of water of weight \( 36 \, \mathrm{g} \). When it is subjected to cooking at \( 100^\circ \mathrm{C} \), then the internal energy for vaporization in \( \mathrm{kJ \, mol^{-1}} \) is _______. [Nearest integer]
[Assume steam to be an ideal gas. Given $\Delta_{\text{vap}}H^\ominus$ for water at \( 373 \, \mathrm{K} \) and \( 1 \, \mathrm{bar} \) is \( 41.1 \, \mathrm{kJ \, mol^{-1}} \); \( R = 8.31 \, \mathrm{J \, K^{-1} \, mol^{-1}} \)]

\( 4.0 \, \text{L} \) of an ideal gas is allowed to expand isothermally into vacuum until the total volume is \( 20 \, \text{L} \). The amount of heat absorbed in this expansion is ______ \( \text{L atm} \).

The molar heat capacity for an ideal gas at constant pressure is \(20.785\,\mathrm{J\,K^{-1}\,mol^{-1}}\). The change in internal energy is \(5000\,\mathrm{J}\) upon heating it from \(300\,\mathrm{K}\) to \(500\,\mathrm{K}\). The number of moles of the gas at constant volume is \(\_\_\_\_\_\_\). [Nearest Integer] (Given \(R=8.314\,\mathrm{J\,K^{-1}\,mol^{-1}}\))

A gas (Molar mass \( = 280 \, \mathrm{g \, mol^{-1}} \)) was burnt in excess \( \mathrm{O_2} \) in a constant volume calorimeter and during combustion the temperature of calorimeter increased from \( 298.0 \, \mathrm{K} \) to \( 298.45 \, \mathrm{K} \). If the heat capacity of calorimeter is \( 2.5 \, \mathrm{kJ \, K^{-1}} \) and enthalpy of combustion of gas is \( 9 \, \mathrm{kJ \, mol^{-1}} \) then amount of gas burnt is ______ \( \mathrm{g} \). (Nearest integer)

2.2g of nitrous oxide ($\text{N}_2\text{O}$) gas is cooled at a constant pressure of 1atm from 310K to 270K causing the compression of the gas from 217.1mL to 167.75mL. The change in internal energy of the process, $\Delta\text{U}$ is '$-x$'J. The value of '$x$' is ________. [Nearest integer]

(Given: atomic mass of $\text{N} = 14\text{ g mol}^{-1}$ and $\text{O} = 16\text{ g mol}^{-1}$. Molar heat capacity of $\text{N}_2\text{O}$ is $100\text{ J K}^{-1}\text{ mol}^{-1}$)

Which of the following relation is not correct?

When \( 5 \) moles of He gas expand isothermally and reversibly at \( 300 \, \mathrm{K} \) from \( 10 \, \text{litre} \) to \( 20 \, \text{litre} \), the magnitude of the maximum work obtained is ________ \( \mathrm{J} \).
[nearest integer] (Given : \( R = 8.3 \, \mathrm{J\,K^{-1}\,mol^{-1}} \) and \( \log 2 = 0.3010 \) )

For the reaction \( \mathrm{H_2F_2(g) \rightarrow H_2(g) + F_2(g)} \)
\( \Delta U = -59.6 \, \text{kJ mol}^{-1} \) at \( 27^\circ \text{C} \).
The enthalpy change for the above reaction is (−) ______ \( \text{kJ mol}^{-1} \) (nearest integer)
Given : \( R = 8.314 \, \text{J K}^{-1} \text{mol}^{-1} \)

Match List-I with List-II

Choose the correct answer from the options given below: