1. Chapter 8 Molecular & Formula Masses

2. Atomic mass The atomic mass is the average mass of an atom.

3. When using atomic masses make sure to round to at least one decimal place.

4. What is the atomic mass of actinium (Ac)?

5. What is the atomic mass of hydrogen (H)?

6. What is the mass of hydrogen (H 2 )?

7. Determine the Molecular Mass of Vitamin A C 20 H 30 O

8. Determine the Molecular Mass of Vitamin A C 20 H 30 O 20 x 12.0 = 240.0 30 x 1.0 = 30.0 1 x 16.0 = 16.0 = 286.0 amu

9. Formula Mass The formula mass is the mass of an ionic compound. An ionic compound is formed from a combination of metals and nonmetals. Formulas masses are calculated the same as molecular masses.

10. Determine the Formula Mass of Calcium Phosphate Ca 3 (PO 4 ) 2

11. Determine the Formula Mass of Calcium Phosphate Ca 3 (PO 4 ) 2 3 x 40.1 = 120.3 2 x 31.0 = 62.0 8 x 16.0 = 128.0 = 310.3 amu

12. The Mole

13. A counting unit Similar to a dozen, except instead of 12, it’s 602 billion trillion 602,000,000,000,000,000,000,000 6.02 X 10 23 (in scientific notation) Amedeo Avogadro (1776 – 1856)This number is named in honor of Amedeo Avogadro (1776 – 1856), and is called Avogadro’s Number.

14. The Mole (mol) 1 mole of cookies = 6.02 X 10 23 cookies 1 mole of cars = 6.02 X 10 23 cars 1 mole of Al atoms = 6.02 X 10 23 atoms

15. How big is a mole? How many cents are in one mole of pennies?

16. How big is a mole? How many cents are in one mole of pennies? 6.02 x 10 23 ¢

17. How big is a mole? How many dollars are in 6.02 x 10 23 ¢?

18. How big is a mole? How many cents are in one mole of pennies? = $6.02 x 10 21 6.02 x 10 23 ¢ 100¢ $1

19. How big is a mole? There are about 6.6 billion (6.6 x 10 9 ) people on earth. If we divided the 1 mole of pennies ($6.02 x 10 21 ) equally among all the people on earth how many dollars would you have?

20. How big is a mole? There are about 6.6 billion (6.6 x 10 9 ) people on earth. If we divided the 1 mole of pennies ($6.02 x 10 21 ) equally among all the people on earth how many dollars would you have? $6.02 x 10 21 6.6 x 10 9 people = $9.1 x 10 11 /person $910,000,000,000 = 910 billion dollars

21. How big is a mole? How many years would it take you to spend your 910 billion dollars if you spent $100,000 per day?

22. How big is a mole? How many years would it take you to spend your 910 billion dollars if you spent $100,000 per day? $9.1 x 10 11 $100,000 day 365 days year = 25,000 years

23. 25,000 years ago Neanderthals died out about 25,000 years ago

24. Homework Finish Mole Worksheet “How Big is a Mole”. Molecular and Formula Mass Worksheet Don’t forget to show your work on your calculations.