The initiation and propagation steps that account for the given reaction. Interpretation: The initiation and propagation steps that account for the given reaction is to predicted. Concept introduction: The chemical reaction which proceeds through the formation of radicals is known as chain reaction. It involves three steps, initiation, propagation and termination. The initiation step occurs in the presence of light. The quantum yield of chain reactions is very high.

[{'sectionSequence': 0, 'sectionHeaderText': '

(a)

\r\n', 'solutionSubsections': [{'sectionName': 'Interpretation Introduction', 'sectionText': "\r\n

To determine: The initiation and propagation steps that account for the given reaction.

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Interpretation: The initiation and propagation steps that account for the given reaction is to predicted.

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Concept introduction: The chemical reaction which proceeds through the formation of radicals is known as chain reaction. It involves three steps, initiation, propagation and termination. The initiation step occurs in the presence of light. The quantum yield of chain reactions is very high.

\r\n", 'sectionSequence': 0, 'computed': {'sectionNameWithHtmlRemoved': 'Interpretation Introduction', 'sectionTextWithHtmlRemoved': 'To determine: The initiation and propagation steps that account for the given reaction. Interpretation: The initiation and propagation steps that account for the given reaction is to predicted. Concept introduction: The chemical reaction which proceeds through the formation of radicals is known as chain reaction. It involves three steps, initiation, propagation and termination. The initiation step occurs in the presence of light. The quantum yield of chain reactions is very high.'}}, {'sectionName': 'Explanation', 'sectionText': '\r\n

Given:

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The balanced chemical equation is,

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Figure 1

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The initiation step involves the generation of bromine free radical. It is expressed as,

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Br2+hv→2Br·

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The bromine radical then reacts with Bu3SnH and forms Bu3Sn· radical.

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Bu3SnH+Br·→Bu3Sn·+HBr

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The first propagation step involves the breaking of bond between cyclohexane ring and bromine as shown in Figure 2.

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Figure 2

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The energy released during the reaction is,

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ΔH1=Energy\u2009between\u2009cyclohexane\u2009and\u2009Br−Energy\u2009of\u2009Bu3SnBr\u2009bond

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The energy required to break bond between cyclohexane and bromine is 309\u2009kJ/mol.

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The energy of Bu3SnBr bond is 522\u2009kJ/mol.

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Substitute the energy required to break bond between cyclohexane and bromine and energy of Bu3SnBr bond in the above xepression

', 'sectionSequence': 2, 'computed': {'sectionNameWithHtmlRemoved': 'Explanation', 'sectionTextWithHtmlRemoved': 'Given: The balanced chemical equation is, Figure 1 The initiation step involves the generation of bromine free radical. It is expressed as, Br 2 + h v → 2 Br · The bromine radical then reacts with Bu 3 SnH and forms Bu 3 Sn · radical. Bu 3 SnH + Br · → Bu 3 Sn · + HBr The first propagation step involves the breaking of bond between cyclohexane ring and bromine as shown in Figure 2. Figure 2 The energy released during the reaction is, Δ H 1 = Energy between cyclohexane and Br − Energy of Bu 3 SnBr bond The energy required to break bond between cyclohexane and bromine is 309 kJ/mol . The energy of Bu 3 SnBr bond is 522 kJ/mol . Substitute the energy required to break bond between cyclohexane and bromine and energy of Bu 3 SnBr bond in the above xepression'}}]}, {'sectionSequence': 1, 'sectionHeaderText': '

(b)

\r\n', 'solutionSubsections': [{'sectionName': 'Interpretation Introduction', 'sectionText': '\r\n

To determine: The value of ΔH for the proposed steps to show that they are energetically feasible.

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Interpretation: The value of ΔH for the proposed steps is to be calculated to show that they are energetically feasible.

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Concept introduction: The chemical reaction which proceeds through the formation of radicals is known as chain reaction. It involves three steps, initiation, propagation and termination. The initiation step occurs in the presence of light. The quantum yield of chain reactions is very high.

\r\n', 'sectionSequence': 0, 'computed': {'sectionNameWithHtmlRemoved': 'Interpretation Introduction', 'sectionTextWithHtmlRemoved': 'To determine: The value of Δ H for the proposed steps to show that they are energetically feasible. Interpretation: The value of Δ H for the proposed steps is to be calculated to show that they are energetically feasible. Concept introduction: The chemical reaction which proceeds through the formation of radicals is known as chain reaction. It involves three steps, initiation, propagation and termination. The initiation step occurs in the presence of light. The quantum yield of chain reactions is very high.'}}]}]