An endothermic reaction with high activation energy for the forward reaction is given by the diagram

For the reaction of one mole of zinc dust with one mole of sulphuric acid in a bomb calorimeter, $∆$U and w corresponds to

• $∆$U < 0, w = 0

• $∆$U < 0, w < 0

• $∆$U > 0, w = 0

• $∆$U > 0, w > 0

Assertion : Water in liquid state is more stable than ice at room temperature.

Reason : Water in liquid form has higher entropy than ice.

• If both assertion and reason are true and reason is the correct explanation of the assertion.

• If both assertion and reason are true but reason is not the correct explanation of the assertion.

• If assertion is true, but reason is false.

• Both assertion and reason are false statements.

Assertion : First ionization energy for nitrogen is lower than oxygen.

Reason : Across a period effective nuclear charge decreases.

• If both assertion and reason are true and reason is the correct explanation of assertion.

• If both assertion and reason are true but reason is not the correct explanation of assertion.

• If assertion is true but reason is false.

• If both assertion and reason are false.

675.

The heat of neutralization of a strong base and a strong acid is 57 kJ. The heat released when 0.5 mole of HNO₃ solution is added to 0.20 moles of NaOH solution, is :

• 11.4 kJ

• 34.7 kJ

• 23.5 kJ

• 58.8 kJ

How much energy is released when 6 moles of octane is burnt in air? Given $∆{\mathrm{H}}_{\mathrm{f}}^{°}$ for CO_2(g) , H₂O_(g) and C₈H_18(l)  respectively are - 490, -240 and +160 kJ/mol.

• -6.2 kJ

• -37.4 kJ

• -35.5 kJ

• -20.0 kJ

For the equilibrium ${\mathrm{H}}_2{\mathrm{O}}_{\left(\mathrm{l}\right)} \rightleftharpoons {\mathrm{H}}_2{\mathrm{O}}_{\left(\mathrm{g}\right)}$ at 1 atm and 298K.

• standard free energy change is equal to zero ($∆{\mathrm{G}}^{°}$= 0)

• free energy change is less than zero ($∆{\mathrm{G}}^{°}$ < 0)

• standard free energy change is less than zero ($∆{\mathrm{G}}^{°}$< 0)

• standard free energy change is greater than zero ($∆$G° > 0).

Of the following which change will shift the reaction towards the product?

${\mathrm{I}}_{2\left(\mathrm{g}\right)} \rightleftharpoons 2{\mathrm{I}}_{\left(\mathrm{g}\right),} ∆{\mathrm{H}}_{\mathrm{f}}^{°} \left(298\mathrm{K}\right) = +150\mathrm{kJ}$

• Increase in concentration of I

• Decrease in concentration of I₂

• Increase in temperature

• Increase in total pressure

One gram sample of NH₄NO₃ is decomposed in a bomb calorimeter. The temperature of the calorimeter increases by 6.12 K. The heat capacity of the system is 1.23 kJ/g/deg. What is the molar heat of decomposition for NH₄NO₃ ?

• -7.53 kJ/mol

• -398.1 kJ/mol

• -16.1 kJ/mol

• -602 kJ/mol

Which one of the following has $∆$S° greater than zero?

• CaO_(s) + CO_2(g) $\rightleftharpoons$ CaCO_3(s)

• NaCl_(aq) $\rightleftharpoons$NaCl_(s)

• NaNO_3(s) $\rightleftharpoons$ Na⁺_(aq) + NO₃^-_(aq)

• N_2(g) + 3H_2(g) $\rightleftharpoons$ 2NH_3(g)