Reference no: EM13183562
1) A compound known to be a pain reliever had the empirical formula C9H8O4. When a mixture of 5.02 mg of the unknown and 50.37 mg of camphor was prepared, the melting point of this mixture was determined. The observed melting point of the mixture was 156 oC. What is the molar mass of this compound? (Use the method of freezing point depression).
2. Protein content in foods, animal feeds, milk, etc. is commonly determined by combustion analysis for nitrogen content in CnHmOpNq. The average N-content of pure proteins is about 16% by weight. In comparison, carbohydrates typically contain no (or little) nitrogen, with C:H:O ratios close to 1:2:1. In recent years, many products including dairy products and pet food manufactured in China were found to be tainted with a synthetic chemical known as Melamine, C3H6N6. Industrial applications of Melamine include polymers and adhesives.
The best known scandal related to Melamine contamination in China is that Melamine was found in milk powder for infants, which led to the deaths of six babies and made some 300,000 ill. Six people were linked to the scandal and two of the convicts were sentenced to death and executed in 2009.
(a) Calculate the N-content by weight in Melamine.
(b) If a diary product is analyzed to have an N-content of 10%, what are the proportions of protein and carbohydrate in this product?
(c) If 100 kg of the same product as in (b) is tainted with 5 kg Melamine, what is the apparent N-content of this product?