Wake-up1. Write the formula for Charles Law.2. Write the formula for Boyle’s Law.3. Bromine gas has a pressure of 536.8 mmHg.

When it is dispensed into a new container, its pressure becomes 784.6 mmHg with a new volume of 412.3 mL. What was the original volume?

4. Identify the Law for #3.

Ideal Gas Laws

What is the IDEAL GAS LAW?What are the variables involved?

What is Avogadro’s Law and didn’t I already learn about him with the mole?

What is an Ideal Gas?

1. Made up of molecules which are in constant random motion in straight lines.

What is an Ideal Gas?

2. The volume of the molecules is negligibly small compared to the volume occupied by the gas

What is an Ideal Gas?

3. All collisions are perfectly elastic. (There is no loss of kinetic energy during the collision.)

Ideal Gas Law EquationEquation is on the Reference Table

What is R?

R is called the Ideal Gas Constant or Universal Gas Constant

Gas Constant ValueSee Reference Table

0.0821 L atm

mole K

62.4

8.314 L kPa mole K

L mmHg mole K

What is the difference between each constant?

Gas Constant ValueSee Reference Table

0.0821 L atm

mole K

62.4

8.314 L kPa mole K

L mmHg mole K

Units of Pressure – Select constant by units used in problem

Proper units of Ideal Gas Formula

When using the Ideal Gas Formula, use correct units!!! Check units before use equation.

P = Pressure (atm)V = Volume (L)

n = Number of moles (mol)R = Gas constant L atm mol K

T = Temperature (K)

Example #1How many moles of N2 are in a 750 mL vessel at

26 degrees Celsius and 625 mm Hg?P = 625 mmHg

V = 750mL 0.750 Ln = ?

R = 62.4 L mmHg mol KT = 26°C 299 K

(625)(0.75) = (n)(62.4)(299)468.75 = (18657.6)(n)

N = 0.025 mol

Example #2If I have 17 moles of gas at a temperature of 67 0C, and a

volume of 88.89 liters, what is the pressure (kPa) of the gas?

P = ? kPaV = 88.89 Ln = 17 mol

R = 8.314 L kPa mol KT = 67°C 340 K

(P)(88.89) = (17)(8.314)(340)(P)(88.89) = (48054.92)

P = 540.6 kPa

Example #3If I have 7.7 moles of gas at a pressure of 0.09 atm and at a temperature of 56 0C, what is the volume of the container

that the gas is in?

P = 0.09 atmV = ?

n = 7.7 molR = 0.0821 L atm mol KT = 56°C 329 K

(0.09)(V) = (7.7)(0.0821)(329)(0.09)(V) = (207.98)

N = 2310.9 L