Determining the exact purity of a sample based on its melting point range is not possible. However, we can infer that the sample is impure because its melting point range is lower than the literature value for pure acetanilide 114-115C . Impurities in a sample typically cause the melting point to decrease and the range to widen.To obtain a more accurate estimation of the purity, other analytical techniques such as chromatography, spectroscopy, or elemental analysis would be necessary.