Molecular weight data for some polymer are tabulated below. Compute the following:
(a) the number-average molecular weight;
(b) the weight-average molecular weight;
Molecular Weight
Range (g/mol) xi wi
8,000–16,000 0.05 0.02
16,000–24,000 0.16 0.10
24,000–32,000 0.24 0.20
32,000–40,000 0.28 0.30
40,000–48,000 0.20 0.27
48,000–56,000 0.07 0.11

answer:

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Explanation:

One of the benefits of working with chlorinated polyvinyl chloride (CPVC) pipe is that it can be cut with a variety of different tools that don’t require any electricity or heat. However, different cutting methods are preferred over others, depending on the application.

When cutting CPVC pipe, it is important to make a square, flat cut. An uneven cut limits the bonding area and weakens the fitting.

To help you make the best possible cut, we’ve put together the following dos and don’ts when cutting CPVC pipe in different situations.