Answer Happy

A new flame atomic-absorption spectroscopic method of determining antimony in the atmosphere was compared with the recommended calorimetric method. For samples from an urban atmosphere the following results were obtained: Sample no. Standard method Antimony found (mg m) 4.16 4.34 4.87 New method Antlmony found (mg m3) 4.38 4.15 4.76 3 5 4.80 5.33 5.48 6 (a) Compare the precision of the two methods and determine if the precisions of the two methods are significantly different or not, using a significand level of 0.05 (95 % confidence level). Assume that the data are normally distributed. Explain your results. (b) Determine if the means of the two methods differ significantly (95 % confidence level). Assume that the data are normally distributed. Explain your results. Note: See appendix for tables and formulas you might need for your calculations