Molecular Weight of Polymers

Q.

As the molecular weight increases, the tensile strength of polymers ...

1. Uncertain

2. Increases

3. Decreases

4. Remains unchanged

Q.

Molecular mass of polymer is

1. small

2. very small

3. negligible

4. large

Q. If $N_1,N_2,N_3,......$ are the number of molecules with molecular masses $M_1,M_2,M_3,......$ respectively, the mass average molecular mass is expressed as?

1. $\frac{\sum N_i{M_i}^2}{\sum N_i{M}_i}$
2. $\frac{\sum N_i{M}_i}{\sum N_i}$
3. $\frac{\sum {M_i}^2}{\sum N_i}$
4. $\frac{\sum N_i{M}_i}{\sum M_i}$