The standard heat of formation, in kcal/mol of \(Ba^{2+}\) is :
[Given : standard heat of formation of \(SO^{2-}_4\) ion (aq) \(= -216~ \text{kcal/mol}\), standard heat of crystallisation of \(BaSO_4 (s)= -4.5~\text{ kcal/mol,}\) standard heat of formation of \(BaSO_4 (s)= -349 ~\text{kcal/mol]}\)
1. \(+133.0 \) 2. \(+220.5\)
3. \(-128.5 \) 4. \(-133.0\)
Subtopic:  Thermochemistry |
 50%
Level 3: 35%-60%
NEET - 2025
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At standard conditions, if the change in the enthalpy for the following reaction is –109 kJ mol
H2(g)+Br2(g)2HBr(g) and the bond energy of H2 and Br2 is 435 kJ mol–1 and 192 kJ mol–1 respectively, what is the bond energy (in kJ mol–1) of HBr?

1. 368 2. 736
3. 518 4. 259
Subtopic:  Thermochemistry |
 57%
Level 3: 35%-60%
NEET - 2020
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When 5 litres of a gas mixture of methane and propane is perfectly combusted at 0°C and 1 atmosphere, 16 litres of oxygen at the same temperature and pressure is consumed. The amount of heat released from this combustion in kJ (\(\Delta \)Hcomb. (CH4) = 890 kJ mol–1, \(\Delta \)Hcomb( C3H8) = 2220 kJ mol–1) is:
1. 38 2. 317
3. 477 4. 32
Subtopic:  Thermochemistry |
 63%
Level 2: 60%+
NEET - 2013
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The enthalpy of fusion of water is 1.435 kcal/mol. The molar entropy change for the melting of ice at 0 oC is:

1. 10.52 cal/(mol K) 2. 21.04 cal/(mol K)
3. 5.260 cal/(mol K) 4. 0.526 cal/(mol K)
Subtopic:  Thermochemistry |
 81%
Level 1: 80%+
AIPMT - 2012
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