Phase diagram can be constructed that show the effect of more than two variables on the phase of a substance. Phase diagrams can use other variables in addition to or in place of temperature, pressure and composition, for example the strength of an applied electrical or magnetic field, and they can also involve substances that take on more than just three states of matter. One type of phase diagram plots temperature against the relative concentrations of two substances in a mixture called a "binary phase diagram", as shown at right. Such a mixture can be either a solid solution, eutectic or peritectic,
Homogeneous and heterogeneous mixtures covalently bound to each other and which retain their own chemical and physical identities; – a substance which has two or more constituent physical substances. Mixtures, in the broader sense, are two or more substances physically in the same place, but these are not chemically combined, and therefore ratios are not necessarily considered. Homogeneous mixtures have the same proportions of the various components throughout a given sample (or multiple samples of different proportion), creating a consistent mixture. However, two homogeneous mixtures of the same pair of substances may differ widely from each other and can be homogenized to make a