Problem 2
What is value of \(\Delta \mathrm{E}\) (heat change at constant volume) for reversible isothermal evaporation of \(90 \mathrm{~g}\) water at \(100^{\circ} \mathrm{C}\) ? Assuming water vapour behaves as an ideal gas and \(\left(\Delta H_{v a p}\right)_{\text {water }}=540\) cals \(g^{-1}\) (a) \(9 \times 10^{3} \mathrm{cals}\) (b) \(6 \times 10^{3} \mathrm{cals}\) (c) \(4.49\) cals (d) none of these
Problem 3
Which of the statement is correct? (a) Slope of adiabatic \(\mathrm{P}-\mathrm{V}\) curve will be same as that of isothermal one. (b) Slope of adiabatic \(\mathrm{P}-\mathrm{V}\) curve is smaller than that in isothermal one (c) Slope of adiabatic \(\mathrm{P}-\mathrm{V}\) curve is larger than that in isothermal one. (d) Slope of adiabatic \(\mathrm{P}-\mathrm{V}\) curve may be smaller or larger depending on the value \(\mathrm{V}\).
Problem 6
At \(298 \mathrm{k}\) in a constant volume calorimeter, \(0.01\) mole of TNT was detonated when 8180 cals of heat was released. Each mole of TNT gives 6 moles of gaseous products on detonation. What is \(\Delta \mathrm{H} /\) mole of TNT exploded? (a) \(-714 \mathrm{kcals} \mathrm{mole}^{-1}\) (b) \(-814 \mathrm{kcals} \mathrm{mole}^{-1}\) (c) \(-914\) kcals mole \(^{-1}\) (d) none of these
Problem 8
A person requires \(2870 \mathrm{kcal}\) of energy to lead normal daily life. If heat of combustion of cane sugar is \(-\) \(1349 \mathrm{kcal}\), then his daily consumption of sugar is (a) \(728 \mathrm{~g}\) (b) \(0.728 \mathrm{~g}\) (c) \(342 \mathrm{~g}\) (d) \(0.342 \mathrm{~g}\)
Problem 9
At \(298^{\circ} \mathrm{K}\) in a constant volume calorimeter, \(0.01\) mole of TNT detonates when 8180 cals of heat was released. Each mole of TNT gives 6 moles of gaseous proudcts on detonation. What is \(\Delta \mathrm{H} / \mathrm{moles}\) of TNT exploder? (a) \(-714 \mathrm{kcals} / \mathrm{mole}\) (b) \(-814 \mathrm{kcals} / \mathrm{mole}\) (c) \(-914 \mathrm{kcals} / \mathrm{mole}\) (d) none of these
Problem 10
What is the amount of heat to be supplied to prepare \(128 \mathrm{~g}\) of \(\mathrm{CaC}_{2}\) by using \(\mathrm{CaCO}_{3}\) and followed by reduction with carbon? Reactions are \(\mathrm{CaCO}_{3}(\mathrm{~s})=\mathrm{CaO}(\mathrm{s})+\mathrm{CO}_{2}(\mathrm{~g}) \quad \Delta \mathrm{H}^{0}=42.8 \mathrm{kcals}\) \(\mathrm{CaO}(\mathrm{s})+3 \mathrm{C}(\mathrm{s})=\mathrm{CaC}_{2}+\mathrm{CO}(\mathrm{g}) \quad \Delta \mathrm{H}^{0}=111 \mathrm{kcals}\) (a) \(102.6 \mathrm{kcals}\) (b) \(221.78 \mathrm{kcals}\) (c) \(307.6 \mathrm{kcals}\) (d) \(453.46 \mathrm{kcals}\)
Problem 11
Ionization energy of \(\mathrm{Al}=5137 \mathrm{~kJ} \mathrm{~mole}^{-1}(\Delta \mathrm{H})\) hydra- tion of \(\mathrm{Al}^{3+}=-4665 \mathrm{~kJ} \mathrm{~mole}^{-1} .(\Delta \mathrm{H})_{\text {bydation }}\) for \(\mathrm{Cl}^{-}=\) \- \(381 \mathrm{~kJ} \mathrm{~mole}^{-1}\). Which of the following statement is correct? (a) \(\mathrm{AlCl}_{3}\) would remain covalent in aqueous solution (b) Only at infinite dilution \(\mathrm{AlCl}_{3}\) undergoes ionisation (c) In aqueous solution \(\mathrm{AlCl}_{3}\) becomes ionic (d) None of these
Problem 16
Molar heat capacity of water in equilibrium with ice at constant pressure is (a) zero (b) infinity \((\infty)\) (c) \(40.45 \mathrm{~J} \mathrm{~K}^{-1} \mathrm{~mol}^{-1}\) (d) \(75.48 \mathrm{~J} \mathrm{~K}^{-1} \mathrm{~mol}^{-1}\)
Problem 18
A cylinder of gas contains \(11.6 \mathrm{~kg}\) of butane, if a normal family needs \(2.0 \times 10^{4} \mathrm{~kJ}\) of energy per day for cooking, how long will the cylinder last \(\left(\Delta H_{\text {combustian of bucane }}=-2600 \mathrm{~kJ} / \mathrm{mol}\right)\). (a) 52 days (b) 26 days (c) 116 days (d) none
Problem 19
Calculate the mass of mercury which can be liberated from \(\mathrm{HgO}\) at \(25^{\circ} \mathrm{C}\) by the treatment of excess \(\mathrm{HgO}\) with \(10 \mathrm{kcal}\) of heat. Standard enthalpy of formation of \(\mathrm{Hg} \mathrm{O}\) is \(21.7 \mathrm{kcal} /\) mole (a) \(92.4 \mathrm{~g}\) (b) \(9.24 \mathrm{~g}\) (c) \(924 \mathrm{~g}\) (d) \(200 \mathrm{~g}\)
