# How to calculate concentration of a solution?

The concentration of a solution is the amount of solute dissolved in a stated volume of a solution. Therefore, Concentration (g/dm3) = mass of solute (g) / volume of solution (dm3) Learn these important conversions: cm3 to dm3 - divide by 1000. dm3 to cm3 - multiply by 1000. Worked Example: Use the equation to work out the concentration of 1.5g of potassium iodide in 150cm3 of solution. Firstly convert 150cm3 of solution in dm3. Remember, cm3 to dm3 - divide by 1000. So, 150cm3/1000 = 0.15dm3. Substitute the values into the equation: Concentration (g/dm3) = mass of solute (g) / volume of solution (dm3). So, 1.5g/0.15dm3 = 10g/dm3

Number of moles= concentration *volume Rearranging this formula gives concentration=number of moles/volume Note that volume must be in terms of dm^3. 1L=1000ml=1000cm^3=1dm^3

Concentration (measured in moles per litre) = amount of solute (measured in moles) divided by the volume of solution (measured in litres) The amount in moles may need to be calculated by dividing the mass (in grams) by the relative mass (in grams per mole)