1. BellRinger Convert 45 inches into feet.

2. Answer 45 in x 1 ft = 3.75 ft 45 in x 1 ft = 3.75 ft 12 in 12 in

3. What is a MOLE?

4. A mole is useful for counting small particles. A mole is useful for counting small particles. The mole is the SI base unit that describes the amount of a substance. The mole is the SI base unit that describes the amount of a substance.

5. A mole is a collection of a very large number of particles. A mole is a collection of a very large number of particles. This number is usually written as This number is usually written as 6.022 x 10 23 /mol and is referred to as Avogadro’s constant. 6.022 x 10 23 /mol and is referred to as Avogadro’s constant.

6. Examples One mole of gumballs is 6.022 x 10 23 gumballs. One mole of gumballs is 6.022 x 10 23 gumballs. One mole of popcorn is 6.022 x 10 23 kernels of popcorn. One mole of popcorn is 6.022 x 10 23 kernels of popcorn.

7. An object’s mass may sometimes be used to “count” it. For example, if a candy shopkeeper knows that 10 gumballs have a mass of 21.4 g, then the shopkeeper can assume that there are 50 gumballs on the scale when the mass is 107 g. What would be the mass of 30 gumballs? An object’s mass may sometimes be used to “count” it. For example, if a candy shopkeeper knows that 10 gumballs have a mass of 21.4 g, then the shopkeeper can assume that there are 50 gumballs on the scale when the mass is 107 g. What would be the mass of 30 gumballs?

8. What is Molar Mass? What is Molar Mass? The mass in grams of 1 mol of a substance is called its molar mass. For example, one mole of carbon- 12 atoms has a molar mass of 12.01 grams. The mass in grams of 1 mol of a substance is called its molar mass. For example, one mole of carbon- 12 atoms has a molar mass of 12.01 grams.

9. Therefore one mole of carbon consists of Therefore one mole of carbon consists of 6.022 x 10 23 carbon atoms, with an average mass of 12.01 amu. 6.022 x 10 23 carbon atoms, with an average mass of 12.01 amu. So 6.022 x 10 23 carbon atoms together have a mass of 12.01 g.

10. Mole Conversion What is the mass of 1 mol of Hydrogen atoms? What is the mass of 1 mol of Hydrogen atoms?

11. Answer 1.008 g 1.008 g Now how many moles in 0.500 g of Hydrogen? Now how many moles in 0.500 g of Hydrogen?

12. 0.500 g H x 1 mol H = 0.496 mol of H 0.500 g H x 1 mol H = 0.496 mol of H 1.008 g H 1.008 g H

13. More Practice !! Complete Question #4 on page 164. Complete Question #4 on page 164.