# Science - Chemistry - Quantitative Chemistry - Concentrations - C3b Flashcards

what is concentration

the amount of substance in a certain volume of solution

if there’s more solute that is in a volume, does the concentration increase or decrease ?

the concentration increases

how do you calculate the concentration ?

mass of solute (g) / volume of solution (dm3)

how can you work out how uncertain your measurements are when doing an experiment ?

repeat the experiment and create a mean result, the range of the results tells you how uncertain the measurements are, the greater the range, the more uncertain

how do you calculate the concentration in moles ?

amount of solute (mol) / volume of solution (dm3)

how do you convert a concentration from g/dm3 to mol/dm3 ?

concentration (g/dm3) / Mr

how do you step by step, calculate concentrations in moles per dm3 ?

- work out how many moles of the ‘known’ substance you have using the formula :

number of moles = concentration (mol/dm3) x volume (dm3) - write down the balanced equation of the reaction and work out how many moles of the ‘unknown’ substance you must have had
- work out the unknown concentration using the formula:

concentration(mol/dm3) = number of moles/volume (dm3)

how do you calculate concentrations in grams per dm3 ?

concentration (mol / dm3) x Mr