Q53.The pH of an aqueous solution containing 1M benzoic acid pKa = 4 . 20 and 1M sodium benzoate is 4 . 5 . The volume of benzoic acid solution in 300 mL of this buffer solution is __________mL.
What This Question Tests
This question applies Hess's Law to calculate the enthalpy change for a target reaction by algebraically manipulating and combining given thermochemical equations.
Concepts Tested
Formulas Used
ΔH_reaction = ΣΔH_products - ΣΔH_reactants
📚 NCERT Sections This Tests
1.30 — Calculate The Amount Of Benzoic Acid (C6H5Cooh) Required For Preparing 250
Chemistry Class 11 · Chapter 1
1.30 Calculate the amount of benzoic acid (C6H5COOH) required for preparing 250 mL of 0.15 M solution in methanol.
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 of Constant Heat Summation
- Year
- 2024
- Shift
- 30 Jan Shift 2
- Q Number
- Q53
- Type
- Numerical
- NCERT Ref
- Class 11 Chemistry Ch 6: Thermodynamics
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