They can be identified by the following reasons:
.A mixture is always heterogenous(except solutions).
A compound is always homogeneous.
. The components of a mixture may be present in any proportion. Whereas,
the components of a compound are entirely different from those of the component elements.
. The components of a mixture can be separated by simple physical methods whereas, the components of th compounds cannot be separated by simple physical methods.
hope this helps..:)