How many grams of carbon dioxide will be produced if 76.4 grams of C2H3Br3 reacted with 49.1 grams of O2? How many grams of the
excess reactant will be left after the reaction is over? Consider the
equation: C2H3Br3+O2 -> CO2+H2O+Br2

The chemical composition of soil varies with depth. an article in communications in soil science and plant analysis describes chemical analyses of soil taken from a farm in western australia. fifty specimens were each taken at depths 50 and 250 cm. at a depth of 50 cm, the average no3 concentration (in mg/l) was 88.5 with a standard deviation of 49.4. at a depth of 250 cm, the average concentration was 110.6 with a standard deviation of 51.5. find a 95% confidence interval for the difference in no3 concentrations at the two depths.