Question

a polymer sample contains equal number of molecules with molecular weight 1*10^5 and 2*10^5 the pdi of the polymer is​

Answer 1

The PDI of the polymer is 1.5 × 10^5.

Given:

A polymer sample contains an equal number of molecules with molecular weights of 1*10^5 and 2*10^5.

To Find:

The PDI of polymer.

Solution:

To find the PDI of polymer we will follow the following steps.

As we know,

PDI is a polydispersity index.

The formula for finding PDI

$= \frac{n1m1 + n2m2}{n1 + n2}$

Here, n1 is several molecules with the weight of m1 while n2 is several molecules with the weight of m2.

But several molecules are of the same molecular weight.

So,

$= \frac{nm1 + nm2}{n + n} = \frac{nm1 + nm2}{2n}$

Now,

Putting values in the above equation we get,

$\frac{nm1 + nm2}{2n} = \frac{1 \times {10}^{5} + \: 2 \times {10}^{5} }{2}$

$= \frac{3 \times {10}^{5} }{2} =1.5 \times {10}^{5}$

Henceforth, the PDI of polymer is 1.5×10^5.

#SPJ1

Answer 2

PDI of the polymer is 1.5*10^5

Given: A polymer sample contains equal number of molecules with molecular weight 1*10^5 and 2*10^5

To Find: PDI of the polymer

Solution:

PDI is the Polydispersity Index of the polymer.

We can find the PDI by applying the following formula:

$\frac{(n_{1}m_{1} )+(n_{2} m_{2})}{n_{1}+ n_{2} }$

Since, n1=n2

Therefore, $\frac{(nm_{1} )+(n m_{2})}{2n} }$

Putting the given values in the above equation,

$\frac{1*10^{5} + 2*10^{5} }{2}$ (n=1)

Solving the above equation we get,

$1.5*10^{5}$

Therefore, the PDI of the polymer is 1.5*10^5