What happens to the mixed melting point if your unknown is mixed with another sample of the same compound?

When a known compound is mixed with another sample of the same compound, the melting point of the mixture is expected to remain unchanged. This occurs because both samples are composed of the same molecules, and thus, they maintain the same crystal lattice structure that contributes to their melting characteristics.

Melting point is a physical property that relies on the uniformity and purity of the sample. When pure samples of the same compound are combined, their intermolecular forces interact consistently, leading to a melting point that reflects the behavior of the individual pure components. Therefore, the melting point of the mixture will remain consistent with that of the pure substance.

In contrast, if the unknown compound were mixed with a different compound, the melting point could change, potentially lowering and indicating impurities or a different composition. However, since in this case the two samples are identical, the purity remains intact, leading to the conclusion that the mixed melting point will stay the same as that of the individual samples.