Sciencemadness Discussion Board

Solution Concentration

pouew - 29-6-2008 at 13:58

How can I work out the concentration of sulphuric acid in a solution of H2SO4/H20 if all I know is the density?

Thanks

kaviaari - 29-6-2008 at 14:22

ρ for density.

n = cV = m/M | *M, m = ρV
cVM = m = ρV | :V :M
c = ρ/M

To this equation we can plug values, for example for conc. sulphuric acid ρ = 1840 g/L and M = 98.something g/mol

c = 1840 g/L / 98 g/mol = 18.something mol/L

[Edited on 30-6-2008 by kaviaari]

Formatik - 29-6-2008 at 16:24

You can also look at a density chart, e.g. like this from a CRC Handbook. Another way to determine concentration but without density, is to form insoluble salts (i.e. BaSO4) and determine the concentration.