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Two reactions are given below:
\( 2\text{Fe(s)} + \dfrac{3}{2}\text{O}_2\text{(g)} \rightarrow \text{Fe}_2\text{O}_3\text{(s)},\ \Delta H^\circ = -822 \,\text{kJ/mol} \)
\( \text{C(s)} + \dfrac{1}{2}\text{O}_2\text{(g)} \rightarrow \text{CO(g)},\ \Delta H^\circ = -110 \,\text{kJ/mol} \)
Then enthalpy change for following reaction \( 3\text{C(s)} + \text{Fe}_2\text{O}_3\text{(s)} \rightarrow 2\text{Fe(s)} + 3\text{CO(g)} \) is _______ \( \text{kJ/mol} \).

When equal volume of \( 1\,\text{M} \) HCl and \( 1\,\text{M} \) \( \text{H}_2\text{SO}_4 \) are separately neutralised by excess volume of \( 1\,\text{M} \) NaOH solution, \( x \) and \( y \) kJ of heat is liberated respectively. The value of \( y/x \) is _______.

The enthalpy of formation of ethane (\( \mathrm{C_2H_6} \)) from ethylene by addition of hydrogen where the bond-energies of \( \mathrm{C{-}H} \), \( \mathrm{C{-}C} \), \( \mathrm{C{=}C} \), \( \mathrm{H{-}H} \) are \( 414 \, \text{kJ} \), \( 347 \, \text{kJ} \), \( 615 \, \text{kJ} \) and \( 435 \, \text{kJ} \) respectively is - ______ \( \text{kJ} \).

Given below are two statements: One is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A): Enthalpy of neutralization of strong monobasic acid with strong monoacidic base is always \( -57 \, \mathrm{kJ} \, \mathrm{mol}^{-1} \).
Reason (R): Enthalpy of neutralization is the amount of heat liberated when one mole of \( \mathrm{H}^{+} \) ions furnished by acid combine with one mole of \( \mathrm{OH}^{-} \) ions furnished by base to form one mole of water.
In the light of the above statements, choose the correct answer from the options given below.

The heat of solution of anhydrous \( \text{CuSO}_4 \) and \( \text{CuSO}_4 \cdot 5\text{H}_2\text{O} \) are \( -70 \, \text{kJ mol}^{-1} \) and \( +12 \, \text{kJ mol}^{-1} \) respectively.
The heat of hydration of \( \text{CuSO}_4 \) to \( \text{CuSO}_4 \cdot 5\text{H}_2\text{O} \) is \( -x \, \text{kJ} \). The value of \( x \) is ___________. (Nearest integer)

Standard enthalpy of vapourisation for \( \mathrm{CCl_4} \) is \( 30.5 \, \mathrm{kJ \, mol^{-1}} \). Heat required for vapourisation of \( 284 \, \mathrm{g} \) of \( \mathrm{CCl_4} \) at constant temperature is ___ \( \mathrm{kJ} \).
(Given molar mass in \( \mathrm{g \, mol^{-1}} \): \( \mathrm{C} = 12 \), \( \mathrm{Cl} = 35.5 \))

The difference in energy between the actual structure and the lowest energy resonance structure for the given compound is:

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JEE Main 2024 29th Jan Morning Shift

The difference in energy between the actual structure and the lowest energy resonance structure for the given compound is: