# Partial and total concentration in solutions

The total pressure of gas mixture equals the sum of partial pressures of its components.

Can this rule be true for liquid concentration?
I.e. can we say: the total concentration of mixture is equal to the sum of partial concentrations of its components?

It's true and false.

For example: 1 Solution with 1mol/L of NaCl and 1mol/L of KBr. The total concentration of salts is 2mol/L.

But the ions concentration are:

Na+ 1mol/L K+ 1mol/L Cl- 1mol/L Br- 1mol/L

Is it clear?

• Thanks for your answer ,but can we say the total concentration of the reactants equals the total concentration of products , Dec 26 '15 at 18:18
• Can you give me an example eg a reaction?
– Koba
Dec 26 '15 at 18:24
• @OmarAlBahra You can always say that the total concentration of reactant atoms equals the total concentration of product atoms. You cannot always say that the total concentration of reactant species equals the total concentration of product species: sometimes this is true, but often it is not. Dec 26 '15 at 18:29
• Thanks @Brian ,like this reaction : ch3cooc2h5 +h2o give ch3cooh +c2h5oh Dec 26 '15 at 18:39
• @OmarAlBahra Yes, that is a reaction where, technically, the total concentrations of reactants and products are equal, because the number of moles of reactants equals the number of moles of products. However, water as a reactant/product is a unique case, since its concentration is so high the change due to reaction is negligible. So, for practical experimental purposes, the total concentration of products would be considered greater than that of reactants. Dec 26 '15 at 19:42