Ch5 Lec 2

Greetings,

If you look on the webpage, you will see that there is an active link to the Exam 2 on Friday April 3. I suggest you have a look at that link to give you more information about the format of the exam.

Note that the chapter 5 outline was given in Lecture 1. I have chosen to focus our attention on only the first 4 sections of chapter 5.

The following two sections are both discussed in the following Crash Course...please note that these crash course videos provide a huge amount of information in a short time period. This one in particular goes into a lot of the background histroy, which is an important thing to know, but will not be on the exam...have a look at:

The Ideal Gas Law: Crash Course Chemistry #12

Gas laws (Sec 5.3)

READ this section...

Summary:

from Crash Course video

Boyle's Law Question

So if you have a container of gas at 1.0 atm pressure (P₁) and 1.0 L volume (V₁)...if the volume is changed to 0.5 L (P₂), then what happens to the pressure?

Use: P₁V₁=P₂V₂;

Answer: 2.0 atm

Charles' Law Question 1

So if you have a balloon of gas at a temperature of 298 K (T₁) and 1.0 L volume (V₁)...if the temperature is changed to 330 K (T₂) what is the new volume?

Use: V₁/T₁=V₂/T₂;

Answer: 1.11 L

Charles' Law Question 2

In Charles Law Question 1, we were dealing with a balloon; a balloon has movable walls and hence the volume can change. If you do the same experiment in a jar (non movable walls) then the pressure will change.

So if you have a 1.0 L jar of gas at a temperature of 298 K (T₁) and a pressure of 1.0 atm (P₁)...if the temperature is changed to 330 K (T₂) what is the new pressure?

Use: P₁/T₁=P₂/T₂;

Answer: 1.11 atm

Avogadro's Law Question 1

If you have 1.0 moles (n₁) of gas and in a balloon with a volume of 22.4 L (V₁), what is the volume of the balloon once 0.25 moles (n₂) of gas is released?

Use: V₁/n₁=V₂/n₂;

Answer: 16.8 L

There is a WebAssign available now (Monday, 8 am) for you to practice gas law questions...