The solution containing $$4.0\,g$$ of a polyvinyl chloride polymer in 1 litre of dioxane was found to have an osmotic pressure $$6.0 \times {10^{ - 4}}$$ atmosphere at $$300\,K,$$ the value of $$R$$ used is 0.082 litre atmosphere $$mol{e^{ - 1}}{K^{ - 1}}.$$ The molecular mass of the polymer was found to be