Chemistry chapter 8 Entry Test MCQs
76. The absolute enthalpy of neutralization of the reaction MgO (s) + 2HCI (aq) → MgCl2 (aq) + H2O(l) will be
a. < – 57.33 KJ/mole
b. -57.33 KJ/mole
c. 57.33 KJ /mole.
d. >-57.33 KJ/ mole
77. For the reaction: S8 (s) + 😯2 (g) → 8SO2(g)
a. ΔH > ΔE
b. ΔH < ΔE
c. ΔH is independent
d. ΔH = ΔE
78. The standard heat of formation of diamond is
a. greater than that of graphite
b. same as that of graphite
c. taken as zero
d. less than that of graphite
79. The lattice energy of NaCl is 780 kJ mol-1 The enthalpies of hydration of Na+ (g) and Cl– (g) ions are -406 KJ mol-1 and -364 kJ mol-1. The enthalpy of solution of NaCl (s) is
a. -10 kJ mol-1
b. 10 kJ mol-1
c. 100 kJ mol-1
d. 736 kJ mol-1
81. In the equation R=E+PV “R” represents
a. Enthalpy of the system
b. Entropy of the system
c. Heat lost by the system
d. Gas constant
82. Enthalpy of an element in standard state is zero. Enthalpy of an exothermic reaction is
a. Zero
b. +ve
c. Unity
d. –ve
83. For the reaction NaOH + HCl → NaCl + H2O, the change in enthalpy is called:
a. Heat of lattice
b. Heat of reaction
c. Heat of combustion
d. Heat of formation
84. The enthalpy change in Bomb calorimeter is measured at constant:
a. Pressure
b. Temperature
c. Volume
d. All of these
85. Enthalpy of neutralization of all strong acids and strong bases has the same value because:
a. Acid always give rise to H+ ions and base always furnish OH– ions
b. Neutralization leads to the formation of salt and water
c. The net chemical change involve the combination of H+ and OH– ions to form water
d. Strong acids and strong bases are ionic substances
86. The value of the enthalpy changes for the process represented by the equation Cl(g) → Cl- (g) is equal to
a. the enthalpy change for atomization of chlorine
b. the first electron affinity of chlorine atom
c. enthalpy of reaction
d. the ionization energy of chlorine
87. Caloric value of fuel can be determined by
a. bomb calorimeter
b. copper calorimeter
c. flame calorimeter
d. glass calorimeter
88. Which of the following relations is correct about sodium chloride formation?
a. ΔH0 f = ΔH0 x – ΔH0 l
b. ΔH0 l = ΔH0 f – ΔH0 x
c. ΔH0 l=ΔH0 f + ΔH°x
d. ΔH0 x = ΔH0 f +ΔH0 l
89. Enthalpy change can be
a. measured experimentally
b. calculated theoretically
c. both A and C
d. It’s a hypothetical phenomenon
90. Heats of formation of H2O(l) and H2O(g) are –285.8kJ and –241.2kJ respectively. The difference of enthalpy equal to +44.6kJ is known as
a. heat of sublimation
b. heat of fusion
c. heat of solidification
d. heat of vaporization
91. Which of the following salts shall cause maximum cooling when one mole of the salt is dissolved in the same amount of water? (integral heat of solution at 298 K is given for each solute)
a. NaCl, ΔH = – 5.35 KJ mol–
b. KNO3, ΔH = 35.4 KJ mol–
c. KBr, ΔH = – 83.3 kJ mol–
d. KOH, ΔH = – 55.6 KJ mol–
93. If heat of formation of a reaction is less than zero then it means that:-
a. Stability of reactants and products is un-predictable.
b. Reactants are more stable than products.
c. Reactants and products have equal stability
d. Products are more stable than reactants.
94. Heat of neutralization for weak acids and weak bases is always:-
a. Greater than 57.4 KJ mol-1
b. Equal to 57.4 KJmol-1
c. Can’t be predicted
d. Less than 57.4 KJmol-1
95. Which statement is not correct about ΔHo?
a. ΔHo of reaction can be > or < zero
b. ΔHo of the reaction depends on temperature
c. ΔHo is always < 0
d. ΔHo of catalyzed and uncatalyzed reaction is same
96. Which of the following processes is always endothermic?
a. Combustion
b. Atomization
c. Solution
d. Neutralization
97. Which one of the following statements is correct for the neutralization of a strong acid by a strong alkali in aqueous solution at 25°C?
a. It is an endothermic process
b. It can be represented as H3O+ + -OH ⎯⎯→2H2O
c. The enthalpy change per mole of H2O formed is independent of the acid or alkali used as they are strong
d. Both B and C
98. For which one of the following compounds standard enthalpy change (ΔHo) can be measured directly by calorimeter?
a. Al2O3
b. CCl4
c. MgO
d. B2O3
99. All of the following processes do not just represent ionization of sodium except:
a. Na(s)——–>Na+(g) +e
b. Na(g)——->Na+(aq) +e
c. Na(g)——–>Na+(g) +e
d. Na(l)—–>Na+(g) +e
100. Which process is not endothermic?
a. 2H2O(g)——>2H2 (g) + O2(g)
b. H2O(s)—->H2O(l)
c. Al2O3(l) + 2Fe(l)——-> 2 Al(s) + Fe2O3(s)
d. H2O(g)——->H2O(l)