a sample of powder was found at a crime scene. it is believed that the powder is cocaine. The only four elements in the compound were determined to be C,H,N, and O. Complete combustion of a 0.563 g sample of the unknown powder with excess O2 produced 1.18g of CO2, 0.310g of H2O and 0.176g NO2. The molar mass of the substance was found to be about 300g/mol. what is the molecular formula of the unknown powder? was the substance cocaine?