The number-average molar mass $\left(\overline{\mathrm{M}}_{\mathrm{N}}\right)$ and weight-average molar mass $\left(\overline{\mathrm{M}}_{\mathrm{w}}\right)$ of a polymer are obtained respectively by
(a)Osmometry and light scattering measurements
(b)Osmometry and viscosity measurements
(c)Light scattering and sedimentation measurements
(d)Viscosity and light scattering measurements
Answer
Answer: A ✓ checked by 4AB · confidence high
The source book printed B; on checking, A is correct — see the explanation.
Explanation
Osmometry counts molecules (M_n); light scattering weights by mass (M_w).