An unknown compound melting at 131 - 133 C. It is thought to be one of the following compounds: trans-cinnamic acid (133-134); b

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An unknown compound melting at 131 - 133 C. It is thought to be one of the following compounds: trans-cinnamic acid (133-134); b

enzamide (128-130); DL-malic acid (131 - 133); or benzoin (135-137). The mixture of melting points of the unknown compound with each of the test compounds listed below. What is the unknown compound? trans-cinnamic acid MP: 110-120 Benzamide MP:130-132 Dl-malic acid MP: 114-124 Benzoin 108-116

Chemistry

1 answer:

Vesnalui [34] · Answer 1 · 2022-04-16T04:46:42+03:00

Answer:

benzamide

Explanation:

Compound melting Point ,ºC Melting Pont Mixture, ºC

X 131 - 133

trans-cinnamic 133 - 134 110 - 120

acid

benzamide 128 - 130 130-132

malic acid 131 -133 114 -124

Benzoin 135 - 137 108 - 116

The compound X is benzamide since the melting point range is the one closest to this compound ( 130-132 ºC)

The reason there is not an exact match is not due due to the presence of impurities. The presence of impurities always lower the melting point ( it is a coligative property such as the melting point depresion of salt and water )

The reason for the deviation must be be some other factors such as preparation of the sample in the capillary, errors in reading the thermometer, rate of heating, etc.