Application of NMR to quantitative analysis

Weight of tablet powder taken for analysis = 0.1228 g Weight of t-butanol internal standard added = 8.0 mg Area of internal standard peak = 7.2 Area of aspirin CH3 peak = 5.65 Area of paracetamol CH3 peak = 6.73 Codeine phosphate CH3 peak = 0.115 MW t-butanol = 74.1 MW aspirin = 180.2 MW paracetamol = 151.2 MW codeine phosphate = 397.4 Number of protons in t-butyl group = 9 

Number of protons in methyl groups of aspirin, paracetamol and codeine = 3. Calculation of the paracetamol in the tablets is shown in Example 8.2. 

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