Ideal Gas Laws

On September 3rd, 2014, our physics class was taught about Ideal Gas Laws. Through many labs, we learned real life applications regarding the Ideal Gas Laws.

Measuring Gas Pressure with Manometer:

Professor Mason started the day off with a demonstration of the gas laws at work with an aluminum can that has hot water boiled in it. He asked us what would happen if he were to put the hot can into a beaker with cold water.

My lab group predicted wrong; the can imploded immediately and drew some of the cold water in.

Next, we were  asked to look at how manometers worked and how it was used to measure the gas pressure.

Daniel blew into the manometer and I marked the volume change on the other end of the straw.

Boyle's Law (P v. V):

Regarding Boyle's Law, we were asked to predict what the relationship was between pressure and volume. My lab group thought it was a direct relationship between the two.

In this lab, we used a pressure sensor, an empty syringe, and the Logger Pro program to record the relationship between pressure and volume. It turns out that the relationship is actually an inverted relationship.

This is Professor Mason's graph.

We were also asked to identify the physical parameters of each variable.

Professor Mason then gave us a problem regarding a diving bell being plunged under seawater.

First, we were asked to find the pressure that the diving bell was experiencing below the surface. Our result was 23 atm.

And then we were asked to find how much of the bell had air. Our conclusion was that 18 cm of the bell was filled with air.

Professor Mason then brought out a vacuum dome with a slightly inflated balloon and he asked the class what would happen if the pressure inside the dome was to slowly disappear.

My lab group made a prediction:

Here is a clip of what happened as the dome was emptied of air and then filled with air again.

Next, Professor Mason inserted three different marshmallows into the vacuum and asked us what would happen to the marshmallows.

My lab group's prediction:

Here is a clip of what happened as the vacuum was emptied of air:

Unfortunately, a part of our prediction was wrong; the marshmallows shrunk in size after the demonstration.

We were then asked a question regarding a balloon that was to be sent into the lower levels of the atmosphere. First, we were asked how much helium was put into the balloon.

And then, we were asked to calculate the volume of the balloon.

We were then asked to find the amount of helium that was needed to initially lift the balloon off the ground.

Charles Law II (P v. T):

We were asked to predict the relationship between pressure and temperature. My lab group though that it was directly proportional.

Professor Mason drew the different relationship graphs on the board.

Professor Mason did a demonstration to show us the relationship between pressure and temperature. For this, he had three beakers filled with water at different temperatures, a 125 mL flask, a pressure sensor, and the Logger Pro program. Below is a graph of the relationship between pressure and temperature.

Charles' Law I (V v. T):

This next demonstration was about the relationship between volume and temperature. To explain, Professor Mason used an empty syringe, the Logger Pro program, a 25 mL flask, and a beaker of water that was being boiled. As the temperature rose in the beaker, the syringe slowly went up in volume because it was being filled with water vapor.