# Convert Concentration (particles/ml) to (mg/ml) [duplicate]

I am struggling with converting concentration from (particles/ml) to (mg/ml). I have the concentration for latex particle (particles/ml) and I want to convert it to (mg/ml).

I worked out the number of moles since I know the the pressure and volume. But I am not sure what to do after that.

First lets see how to get from particles $N$ per volume to mass $m$ per volume.
$$\frac{N}{V}\cdot \frac{1}{N_\mathrm A}=\frac{n}{V}$$
Multiplying moles with molar mass gives mass. $$\frac{n}{V}\cdot M=\frac{m}{V}$$ Concluding: $$\frac{N}{V}\cdot \frac{M}{N_\mathrm A}=\frac{m}{V}$$