he literature value for the melting point of aspirin is 135°C. Suppose that a sample of aspirin prepared in
Experiment 41 melts over the temperature range 125–128°C. What does this result suggest about the
purity of this sample of aspirin?
To determine the purity of a sample of aspirin based on its melting point, we compare the observed melting point range to the literature value.
In this case, the literature value for the melting point of aspirin is 135°C. The observed melting point range for the sample is 125–128°C.
If the observed melting point range is significantly lower than the literature value, it suggests that the sample may contain impurities. Impurities can lower the melting point and broaden the melting point range.
In this scenario, the observed melting point range (125–128°C) is indeed lower than the literature value (135°C). Therefore, it indicates that the sample of aspirin may contain impurities.
To determine the purity of the sample of aspirin, we need to compare its melting point with the literature value.
In this case, the literature value for the melting point of aspirin is 135°C. The sample prepared in Experiment 41 melted over the temperature range 125-128°C.
To analyze the purity of the sample, we can consider the following scenarios:
1. If the sample melted at a temperature significantly lower than the literature value (e.g., below 125°C), it would suggest that the sample is impure. Other substances may be present in the sample that lower its melting point.
2. If the sample melted at a temperature within the given range (125-128°C), it suggests that the sample is relatively pure. However, further analysis is required to determine the extent of purity.
3. If the sample melted at a temperature higher than the given range (e.g., above 128°C), it could imply that the sample is also impure. It could be due to the presence of impurities raising the melting point of the aspirin.
Based on the given information, since the sample's melting point range (125-128°C) does not match the literature value (135°C), it suggests that this sample of aspirin is impure, containing substances that affect its melting point.