A copolymer consisting of vinyl acetate and vinyl chloride has a molar molecular mass of 10 000 g/mol and a degree of polymerization, DP, of 200. The molecular weight of a vinyl chloride mer is 62.5 g/mol. The molecular weight of a vinyl acetate mer is 86 g/mol. The mole fraction of vinyl chloride is most nearly O A. 0.1 LOB. 0.3 loc. 0.5 OD. 0.6

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Netta00 Netta00 · Answer 1 · 2019-09-25T12:00:15+02:00

Answer:

C. 0.5

Explanation:

Given that

Molecular mass= 10,000 g/mol

DP= 200

Molecular weight of vinyl chloride = 62.5 g/mol

Molecular weight of vinyl acetate = 86 g/mol

Lets take mole fraction of vinyl chloride is x

And mole fraction of vinyl acetate is (1-x)

As we know that

Mass = number of mole x molecular wight

For vinyl chloride

Mass of vinyl chloride=62.5 x

For vinyl acetate

Mass of vinyl acetate =86(1-x)

Total mass(mass of monomer) = 62.5 x + 86 (1-x) ----1

We know that total weight of polymer given as

total weight of polymer = DP x Mass of monomer

10,000 =200(62.5 x + 86 - 86 x)

23.5 x = 36

x=1.53

This can not be possible .because be assumed that x is less than 1.

If we replace 10,000 by 15,000 then

15,000 =200(62.5 x + 86 - 86 x)

75 =62.5 x + 86 - 86 x

x=0.46

x=0.5

So the answer C is correct.