Q53.The enthalpy of formation of ethane (C2H6) from ethylene by addition of hydrogen where the bond-energies of C −H, C −C, C = C, H −H are 414 kJ, 347 kJ, 615 kJ and 435 kJ respectively is kJ
What This Question Tests
This question requires calculating the enthalpy of a hydrogenation reaction using given bond energy values. It involves drawing structures and correctly counting bonds broken and formed.
Concepts Tested
Formulas Used
ΔH_reaction = Σ(Bond energies of reactants) - Σ(Bond energies of products)
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13.5 The Q value of a nuclear reaction A + b ® C + d is defined by Q = [ mA + mb – mC – md]c2 where the masses refer to the respective nuclei. Determine from the given data the Q-value of the following reactions and state whether the reactions are exothermic or endothermic. (i) 11 H+13 H →12 H+12 H (ii) 126 C+126 C →1020 Ne+ 24 He Atomic masses are given to be m ( 12 H ) = 2.014102 u m ( 13 H) = 3.016049 u m ( 126 C ) = 12.000000 u m ( 1020 Ne ) = 19.992439 u
📋 Question Details
- Chapter
- Thermodynamics & Thermochemistry
- Topic
- Enthalpy of reaction from bond energies
- Year
- 2024
- Shift
- 04 Apr Shift 1
- Q Number
- Q53
- Type
- Numerical
- NCERT Ref
- Class 11 Chemistry Ch 6: Thermodynamics
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