Catalyst 1. What is the coldest possible temperature. What happens at this point? 2. You have a gas that has a pressure of 2 atm and a volume of 5 L. What is the new pressure if the gas is compressed to 2 L? End

Test Tube and Balloons

Lecture 5.4 – Combined Gas Law and

Today’s Focus Question – Why is there more smog in the summer than the winter?

Today’s Learning Targets LT 5.10 – I can calculate the various properties of a gas using the Ideal Gas Law and the Combined Gas Law.

What is the Combined Gas Law?

I. Gas Law Review Boyle’s Law (inverse relationship): P i V i =P f V f Gay-Lussac’s Law (direct relationship): Charles Law (direct relationship):

II. Combined Gas Laws We can combine Boyle’s Law, Charles Law, and Gay-Lussac’s Law into one equation. The combined Gas Law equation is:

What is the Ideal Gas Law?

I. Ideal Gas Law Based on the relationships studied by Boyle, Charles, and Gay – Lussac An ideal gas is an imaginary gas whose particles are infinitely small and do not interact with each other.

II. The Ideal Gas Law The Ideal Gas Law is: PV=nRT P=pressure V=volume in L n=moles R=Gas constant ( (L atm)/(K mol)) T=temperature in Kelvin.

Class Example If I have 4 moles of a gas at a pressure of 5.6 atm and a volume of 12 L, what is the temperature of this gas?

Table Talk If I have an unknown quantity of gas at a pressure of 1.2 atm, a volume of 31 L, and a temperature of 87 o C, how many moles of gas do I have?

Stop and Jot If I contain 3 moles of gas in a container with a volume of 60 L and a temperature of 400 K, what is the pressure inside this container?

Snake Game We need to be able to do Ideal Gas Law Problems with relative quickness, therefore we are going to be doing the snake game to determine the answer to ideal gas law problems You will be answering the problems alone Many of the problems will require you to spot the error in the answer

Question 1 If I have 4 moles of a gas at a pressure of 5.6 atm and a volume of 12 liters, what is the temperature? Remember R= (Lxatm)/(Kxmol)

Question 2 If I have an unknown quantity of gas at a pressure of 1.2 atm, a volume of 31 liters, and a temperature of 360 K, how many moles of gas do I have?

Question 3 If I contain 3 moles of gas in a container with a volume of 60 liters and at a temperature of 400 K, what is the pressure inside the container?

Question 4 Spot the error in this answer: Problem – If I have moles of gas at a temperature of -200 o C and a pressure of 1.75 atmospheres, what is the volume of the gas? Answer –

Question 5 Spot the error in this answer: If four moles of a gas at a pressure of 5.4 atmospheres have a volume of 120 liters, what is the temperature?

Question 6 Spot the error in this answer: If I have 72,000 mL of gas held at a pressure of 3.4 atm and a temperature of 225 K, how many moles of gas do I have?

Question 7 A weather ballon is filled with 150 L of helium at 23 o C and 1.00 atm. What volume does the balloon have when it has risen to a point in the atmosphere where the pressure is atm and the temperature is -31 o C?

Question 8 If I initially have a gas at a pressure of 12 atm, a volume of 23 liters, and a temperature of 200 K, and then I raise the pressure to 14 atm and increase the temperature to 300 K, what is the new volume of the gas?

Question 9 A gas takes up a volume of 17 liters, has a pressure of 2.3 atm, and a temperature of 299 K. If I raise the temperature to 350 K and lower the pressure to 1.5 atm, what is the new volume of the gas?

Question 10 A gas at 5 L and STP is increased to 5 atm and 500 K, what is the new pressure?

Question 11 If I have 17 liters of gas at a temperature of 67 0 C and a pressure of atm, what will be the volume of the gas if I bring the gas to STP?

Question 12 You have a 15 moles of a gas at STP. What volume does this gas occupy?

Closing Time Lab Report Due Thursday/Friday!