When polyethylene is made by free radical polymerization , the resulting polymer has a significant amount of branching, resulting in low-density polyethylene. When styrene undergoes free radical polymerization, on the other hand, very little branching occurs. This phenomenon is to be explained. Concept introduction: Free radical polymerization is an example of chain-growth polymerization, one general class of polymerization reactions. In chain-growth polymerization, reaction occurs at the end of the growing chain, and each reaction lengthens the polymer chain by a single repeating unit. Branching can occur during chain-growth polymerization if the reactive site becomes located somewhere in the middle of a chain. The free radical at one end of one growing chain encounters a hydrogen atom in the middle of another chain. After hydrogen atom abstraction, the original free radical has become a terminated closed-shell species and the reactive radical appears somewhere in the middle of another chain. Further polymerization at the new radical creates a branch in the chain. Due to this reason, polyethylene has a significant amount of branching. But in polystyrene, phenyl groups are present which sterically hinder the radicals that may abstract H atoms. Therefore, the bulky phenyl rings prevent branching.

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Definition Definition Chemical process in which one or more monomers combine to produce a very large chain-like molecule called a polymer. The functional groups present on the monomers and their steric effects are responsible for polymerization through a sequence of reactions that vary in complexity. There exists a stable covalent chemical bond between monomers that sets apart polymerization from other processes.

Chapter 26, Problem 26.50P

Interpretation Introduction

Interpretation:

When polyethylene is made by free radical polymerization, the resulting polymer has a significant amount of branching, resulting in low-density polyethylene. When styrene undergoes free radical polymerization, on the other hand, very little branching occurs. This phenomenon is to be explained.

Concept introduction:

Free radical polymerization is an example of chain-growth polymerization, one general class of polymerization reactions. In chain-growth polymerization, reaction occurs at the end of the growing chain, and each reaction lengthens the polymer chain by a single repeating unit. Branching can occur during chain-growth polymerization if the reactive site becomes located somewhere in the middle of a chain. The free radical at one end of one growing chain encounters a hydrogen atom in the middle of another chain. After hydrogen atom abstraction, the original free radical has become a terminated closed-shell species and the reactive radical appears somewhere in the middle of another chain. Further polymerization at the new radical creates a branch in the chain. Due to this reason, polyethylene has a significant amount of branching. But in polystyrene, phenyl groups are present which sterically hinder the radicals that may abstract H atoms. Therefore, the bulky phenyl rings prevent branching.

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2. 200 LOD For an unknown compound with a molecular ion of 101 m/z: a. Use the molecular ion to propose at least two molecular formulas. (show your work) b. What is the DU for each of your possible formulas? (show your work) C. Solve the structure and assign each of the following spectra. 8 6 4 2 (ppm) 150 100 50 ō (ppm) 4000 3000 2000 1500 1000 500 HAVENUMBERI-11

Complete the spectroscopy with structure

Answer 2

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Definition Definition Chemical process in which one or more monomers combine to produce a very large chain-like molecule called a polymer. The functional groups present on the monomers and their steric effects are responsible for polymerization through a sequence of reactions that vary in complexity. There exists a stable covalent chemical bond between monomers that sets apart polymerization from other processes.

Chapter 26, Problem 26.50P

Interpretation Introduction

Interpretation:

When polyethylene is made by free radical polymerization, the resulting polymer has a significant amount of branching, resulting in low-density polyethylene. When styrene undergoes free radical polymerization, on the other hand, very little branching occurs. This phenomenon is to be explained.

Concept introduction:

Free radical polymerization is an example of chain-growth polymerization, one general class of polymerization reactions. In chain-growth polymerization, reaction occurs at the end of the growing chain, and each reaction lengthens the polymer chain by a single repeating unit. Branching can occur during chain-growth polymerization if the reactive site becomes located somewhere in the middle of a chain. The free radical at one end of one growing chain encounters a hydrogen atom in the middle of another chain. After hydrogen atom abstraction, the original free radical has become a terminated closed-shell species and the reactive radical appears somewhere in the middle of another chain. Further polymerization at the new radical creates a branch in the chain. Due to this reason, polyethylene has a significant amount of branching. But in polystyrene, phenyl groups are present which sterically hinder the radicals that may abstract H atoms. Therefore, the bulky phenyl rings prevent branching.

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Answer 3

Question

Definition Definition Chemical process in which one or more monomers combine to produce a very large chain-like molecule called a polymer. The functional groups present on the monomers and their steric effects are responsible for polymerization through a sequence of reactions that vary in complexity. There exists a stable covalent chemical bond between monomers that sets apart polymerization from other processes.

Chapter 26, Problem 26.50P

Interpretation Introduction

Interpretation:

When polyethylene is made by free radical polymerization, the resulting polymer has a significant amount of branching, resulting in low-density polyethylene. When styrene undergoes free radical polymerization, on the other hand, very little branching occurs. This phenomenon is to be explained.

Concept introduction:

Free radical polymerization is an example of chain-growth polymerization, one general class of polymerization reactions. In chain-growth polymerization, reaction occurs at the end of the growing chain, and each reaction lengthens the polymer chain by a single repeating unit. Branching can occur during chain-growth polymerization if the reactive site becomes located somewhere in the middle of a chain. The free radical at one end of one growing chain encounters a hydrogen atom in the middle of another chain. After hydrogen atom abstraction, the original free radical has become a terminated closed-shell species and the reactive radical appears somewhere in the middle of another chain. Further polymerization at the new radical creates a branch in the chain. Due to this reason, polyethylene has a significant amount of branching. But in polystyrene, phenyl groups are present which sterically hinder the radicals that may abstract H atoms. Therefore, the bulky phenyl rings prevent branching.

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Check out a sample textbook solution

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Answer 4

Question

Definition Definition Chemical process in which one or more monomers combine to produce a very large chain-like molecule called a polymer. The functional groups present on the monomers and their steric effects are responsible for polymerization through a sequence of reactions that vary in complexity. There exists a stable covalent chemical bond between monomers that sets apart polymerization from other processes.

Chapter 26, Problem 26.50P

Interpretation Introduction