# What is the amount of a substance in a given volume is called?

Nov 26, 2016

$\text{The concentration.........?}$

#### Explanation:

When a solute is dissolved in a solvent, it expresses a $\text{concentration}$.

Typically, $\text{concentration}$ $=$ $\text{Amount of solute in moles"/"Volume of solution in litres}$.

And thus, typically, $\text{concentration}$ has units of $m o l \cdot {L}^{-} 1$; this is typically called the $\text{molarity}$ of the solution.

Depending on whether you are in 1st year university or not, $\text{concentration}$ can be expressed in terms of $\text{molality}$, where $\text{molality"="Moles of solute"/"Mass of solvent in kg}$.

$\text{Molality}$ is thus a temperature invariant term (because volume can alter with temperature), but at low to moderate concentrations in aqueous solutions, $\text{molality "-=" molarity}$.

And thus for solutes, we write $C = \frac{n}{V}$ $\text{(C = concentration; n = amount of moles; V = volume in litres)}$; given 2 terms we can find the third.