Answer and Explanation:
In comparing the melting point values of the sample and the literature, we can observe the following:
1. Sample melting point value: 113-114°C
2. Literature melting point range for pure acetanilide: ~20°C
The sample melting point value falls within the literature range for pure acetanilide, indicating that the sample is likely pure.
Now, let's compare the melting point range and behavior of the original impure acetanilide to explain any difference:
1. Original impure acetanilide melting point range: 85-98°C
The original impure acetanilide has a broader and lower melting point range compared to the pure acetanilide in the literature. This suggests that impurities present in the original acetanilide sample may be affecting its melting behavior.
Impurities can disrupt the regular packing of molecules in the solid state, making it more difficult for the sample to achieve a well-defined melting point. This can result in a broader and lower melting point range.
In contrast, pure and solvent-free acetanilide has a more defined and narrower melting point range due to the absence of impurities. The molecules in the pure sample can pack more closely, allowing for a more precise melting temperature.
Therefore, the difference in melting point ranges between the original impure acetanilide and pure acetanilide in the literature can be attributed to the presence of impurities affecting the sample's melting behavior.