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प्रश्न
Answer in brief.
What is entropy? Give its units.
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उत्तर
- Entropy is a measure of molecular disorder or randomness.
- An entropy change of a system is equal to the amount of heat transferred (Qrev) to it in a reversible manner divided by the temperature (T) in Kelvin at which the transfer takes place. Thus,
`triangle "S" = ("Q"_"rev")/"T"` - Units of entropy: J K–1
Note: Entropy or its change ∆S is a state function and depends on the initial and final states of the system and not on the path connecting two states
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संबंधित प्रश्न
Define entropy.
In which of the following, entropy of the system decreases?
Answer the following in one or two sentences.
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Answer the following in one or two sentences.
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Answer the following question.
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Identify the INCORRECT statement.
For a process, entropy change of a system is expressed as ________.
In which of the following, ∆S is positive?
Which one of the following has ΔS0 greater than zero?
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For a reaction ΔH = - 30kJ and ΔS = - 45 JK-1, at what temperature reaction changes from spontaneous to non-spontaneous?
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Identify whether the following pair have larger entropy or not. If yes then Why?
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State whether the reaction is spontaneous or not. (Given: KP = 3.358 × 1017, T = 25° C, R = 8.314 × 10−3 kJK−1 moI−1)
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The entropy of vaporisation of benzene is 85 J K−1 mol−1. When 117 g of benzene vaporises at its boiling point, what is the entropy change of the surroundings if the process is at equilibrium?
Change in Gibbs energy for a certain reaction at 300 K is –24 kJ and change in enthalpy is –16 kJ. What is the entropy change of the reaction?
