avogadro's law in science 10gaslaws.pptx

State the relationship between amount of gas and it's volume

1. AVOGADRO’S LAW

2. When you inflate a balloon, its volume increases because you add more air molecules. If the balloon has a small hole, the air leaks out and causes the air volume to decrease.

3. Amedeo Avogadro, an Italian chemist and physicist, formulated the Avogadro’s Law, which states that at constant temperature and pressure, the volume of a gas is directly related to its number of moles. Amedeo Avogadro

4. This law is expressed as: FORMULA In Avogadro’s law, the following formulas are to be used when three variables are given and one is unknown: Where V1 and n1 are the initial volume and amount of gas; V2 and n2 are the final volume and amount of gas at constant pressure and temperature.

5. EXAMPLE: A weather balloon filled with 2.0 mol helium has a volume of 40.0 L. To what volume, in L, will the balloon expand if 4.0 mol of helium is added, to give a total of 6.0 mol of helium keeping the temperature and pressure the same?

6. EXAMPLE: If 2 moles of a gas occupy a volume of 10 liters at a certain temperature and pressure, how many moles of the gas would occupy a volume of 20 liters at the same temperature and pressure? Solution: Given: n 1​=2 moles V 1​=10 liters V 2​=20 liters n2= ? Formula: n 2​= V 2​× n 1 / v1​​ Substitute the values: n 2​= 20 x 2 / 10​ n 2​= 40 / 10​ n 2​= 4

7. Problem 1: If 4 moles of a gas occupy a volume of 50 liters at a certain temperature and pressure, what volume would 6 moles of the gas occupy at the same temperature and pressure? In a ½ crosswise paper, solve the following problems: Problem 2: If 3 moles of a gas occupy a volume of 30 liters at a certain temperature and pressure, how many moles of the gas would occupy a volume of 15 liters at the same temperature and pressure?

8. QUESTIONS? If you have questions feel free to ask.