Solutions, Concentration, Dilution, and Titration Calculations

Most reactions that chemists carry out take place in solution, so being able to describe and calculate concentration is an essential skill. A solution consists of a solute dissolved in a solvent, and concentration expresses how much solute is present in a given volume of solution. The most useful measure in chemistry is molar concentration, defined as the amount of solute in moles per cubic decimeter of solution, with units of $\text{mol dm}^{-3}$. One cubic decimeter equals one liter, or $1000 \text{ cm}^3$. The defining equation is:

$$c = \frac{n}{V}$$

where $c$ is concentration in $\text{mol dm}^{-3}$, $n$ is amount in moles, and $V$ is volume in $\text{dm}^3$. Because laboratory volumes are usually measured in $\text{cm}^3$, remember to divide by $1000$ to convert to $\text{dm}^3$ befo