1 / 24

Chapter 8

Chapter 8. Molecular & Formula Masses. Atomic mass. The atomic mass is the average mass of an atom. When using atomic masses make sure to round to at least one decimal place. What is the atomic mass of actinium (Ac)?. What is the atomic mass of hydrogen (H)?.

oren-livingston
Download Presentation

Chapter 8

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  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 (H2)?

  7. Determine the Molecular Mass of Vitamin A C20H30O

  8. Determine the Molecular Mass of Vitamin A C20H30O 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 Ca3(PO4)2

  11. Determine the Formula Mass of Calcium Phosphate Ca3(PO4)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. The Mole • 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 1023 (in scientific notation) • 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 1023 cookies • 1 mole of cars = 6.02 X 1023 cars • 1 mole of Al atoms = 6.02 X 1023 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 1023¢

  17. How big is a mole? • How many dollars are in 6.02 x 1023¢?

  18. How big is a mole? • How many cents are in one mole of pennies? = $6.02 x 1021 6.02 x 1023¢ $1 100¢

  19. How big is a mole? • There are about 6.6 billion (6.6 x 109) people on earth. • If we divided the 1 mole of pennies ($6.02 x 1021) 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 109) people on earth. • If we divided the 1 mole of pennies ($6.02 x 1021) equally among all the people on earth how many dollars would you have? $6.02 x 1021 = $9.1 x 1011/person 6.6 x 109 people $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 1011 year day $100,000 365 days = 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.

More Related