Q54.At 298 K, the enthalpy of fusion of a solid X is 2 . 8 kJ mol-1 and the enthalpy of vaporisation of the liquid X is 98 . 2 kJ mol-1. The enthalpy of sublimation of the substance X in kJ mol-1 is ______. (in nearest integer)
What This Question Tests
This question requires recalling the relationship between enthalpy of sublimation, fusion, and vaporization, applying a direct sum to calculate the unknown enthalpy.
Concepts Tested
Formulas Used
ΔHsublimation = ΔHfusion + ΔHvaporisation
📚 NCERT Sections This Tests
2.8 — The Conductivity Of 0.20 M Solution Of Kcl At 298 K Is 0.0248 S Cm–1. Calculate
Chemistry Class 11 · Chapter 2
2.8 The conductivity of 0.20 M solution of KCl at 298 K is 0.0248 S cm–1. Calculate its molar conductivity.
1.35 — Henry’S Law Constant For The Molality Of Methane In Benzene At 298 K Is
Chemistry Class 11 · Chapter 1
1.35 Henry’s law constant for the molality of methane in benzene at 298 K is 4.27 × 105 mm Hg. Calculate the solubility of methane in benzene at 298 K under 760 mm Hg.
3.23 — The Rate Constant For The Decomposition Of Hydrocarbons Is 2.418 × 10–5S–1
Chemistry Class 11 · Chapter 3
3.23 The rate constant for the decomposition of hydrocarbons is 2.418 × 10–5s–1 at 546 K. If the energy of activation is 179.9 kJ/mol, what will be the value of pre-exponential factor.
📋 Question Details
- Chapter
- Thermodynamics & Thermochemistry
- Topic
- Hess's Law and enthalpy changes
- Year
- 2021
- Shift
- 25 Jul Shift 1
- Q Number
- Q54
- Type
- Numerical
- NCERT Ref
- Class 11 Chemistry Ch 6: Thermodynamics
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