The Grass Doctor

chem problems?

i didnt get these three... 1. Earth's population is 6.5billion. Supose every person on Earth participates in a process of counting identical particles at the rate of two particles per second. How many years would it take to count 6.0 X 10^23 particles? Assume there are 365 days in a year 2. Urea [(NH2)3CO] is used for fertilizer. calculate the # of N, C, O, and H atoms in 1.68 X 10^4 g of urea 3. Hydrogen has two stable isotopes. Sulfer has four stable isotopes. How many peaks would you observe in the mass pectrum of the positive ion of hydrogen sulfide, H2S+? Assume no decomposition of the ion into smaller fragments

Public Comments

1. In scientific notation, the population is 6.5 x 10E9. A year has 3.15 x 10E7 seconds. At two particles a second, that's 6.30 x 10E7 Multiplying the population by the number counted, per person, in a year, you get 4.10 x 10E17 particles per year A mole of particles is 6.02 x 10E23, so divide 6.02 x 10E23 / 4.10 x 10E17. I don't have a calculator handy, so this last number is a SWAG 1.5 x 10E6 years That's: 1,500,000 years. It'll take a while.