A student measures the melting point of an unknown solid to be 167.5 - 170°C. She thinks she either has mannitol or tartaric acid which have the literature melting point ranges shown
below.
MP of Mannitol 167 - 170 °C
MP of Tartartic Acid 168-170 °C
ont 2
She makes a 50/50 mixture of her unknown with mannitol and another 50/50 mixture with
tartartic acid. She measures the melting points of her mixtures as shown below. Is her
unknown mannitol or tartaric acid? Explain your reasoning.
sur BOT KUCE
MP of 50/50 mixture of unknown with mannitol 167.6 - 170.0 °C
MP of 50/50 mixture of unknown with tartaric acid 143.2 - 154.8 °C