Question

What is the concentration of a) 0.8g of NaOH in 100cm of water b) 3.65g of HCl in 2dm of Ethanol​

Answer 1

Explanation:

The concentration of a solution can be shown in g/dm3 or mol/dm3. It is often more useful to know the concentration of a reactant in mol/dm3 so that the amount of reactant in a given volume can be calculated.

Concentration using moles

The concentration of a solution can be calculated using:

the amount of dissolved solute in moles, mol

the volume of solution (or solvent) in cubic decimetres, dm3

Concentration =

Concentration = 0.25 mol/dm3

Volume units

Volumes used in concentration calculations must be in dm3, not in cm3. It is useful to know that 1 dm3 = 1000 cm3. This means:

divide by 1000 to convert from cm3 to dm3

multiply by 1000 to convert from dm3 to cm3