Q54.The pH of ammonium phosphate solution, if pka of phosphoric acid and pkb of ammonium hydroxide are 5. 23 and 4. 75 respectively, is
What This Question Tests
This question requires calculating the average bond energy using the standard enthalpies of formation of the compound and its constituent atoms, applying Hess's Law indirectly.
Concepts Tested
Formulas Used
ΔrH = Σn ΔfH(products) - Σn ΔfH(reactants)
ΔrH = ΣBE(reactants) - ΣBE(products)
📚 NCERT Sections This Tests
3.23 — The Rate Constant For The Decomposition Of Hydrocarbons Is 2.418 × 10–5S–1
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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.
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4.14 Describe the preparation of potassium dichromate from iron chromite ore. What is the effect of increasing pH on a solution of potassium dichromate?
📋 Question Details
- Chapter
- Thermodynamics & Thermochemistry
- Topic
- Bond enthalpy calculations
- Year
- 2021
- Shift
- 26 Feb Shift 2
- Q Number
- Q54
- Type
- Numerical
- NCERT Ref
- Class 11 Chemistry Ch 6: Thermodynamics
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