Concept explainers
The number of carbon and hydrogen atoms in the unit cell of polyethylene.
Answer to Problem 2.19P
The number of carbon atoms in the unit cell of polyethylene is
Explanation of Solution
Given:
The given figure is,
Figure (1)
The density of crystalline polyethylene
From above figure,
The lattice parameter
The lattice parameter
The lattice parameter
Formula used:
The equation for density of poly-ethylene is given by,
Here,
The hydrogen atoms are twice in number as that of carbon atoms.
Substitute
Here,
Calculation:
The molecular mass of carbon is
The molecular mass of hydrogen is
The value of Avogadro’s number is
Substitute
Since
Conclusion:
The number of carbon atoms in the unit cell of polyethylene is
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Chapter 2 Solutions
Materials Science And Engineering Properties
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- Materials Science And Engineering PropertiesCivil EngineeringISBN:9781111988609Author:Charles GilmorePublisher:Cengage Learning