Laboratorio gases

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LAB REPORT

Experiment # 1:

Title: Equation of an ideal gas
Objective:
* Observe how a balloon expands and compress.
* Observe how a change of temperature is equal to a change of sate.

Materials:
* 600 mL beaker
* 125 mL Erlenmeyer
* 1 balloon
* Water
* Bunsen Burner
* Lab arm
* Square support
* Lab glasses

Theoreticalconcepts:
* Bernoulli Effect: Decreasing of the pressure in a fluid produce when it is passing through a small section of a tube as a consequence of an increases in its kinetic energy. The venturi effect is an enlargement of the Bernoulli Effect.
* Pressure: The amount of force that is exerted over an area.
* Temperature: The heat of something measured on a scale such as the Kelvin,Fahrenheit and Celsius.
* Volume: The size of a three-dimensional space enclosed within or occupied by an object.

Procedure:
1. Place 300 mL of water in a beaker.
2. Place the beaker over the burner until it reaches a temperature of 100°C, the boiling point of water at sea level.
3. Turn off the gas of the burner.
4. Place the balloon with a little bit of air on the top of theerlenmeyer.
5. Place it in the hot water for about 5 minutes.
6. Place a piece of tape on top of the surface of the balloon.
7. Take out the balloon from the water and place it immediately into cold water.
8. Observe and data your results.

Observations:

Balloon

Tape

Erlenmeyer
Square support
Burner
beaker
Lab arm

Directly
Proportional

Analysis:
For turningon the Bunsen burner, we open the passage of gas. These types of burners work by being tide to a gas valve and an air valve that can be controlled. The mixture of both substances makes a flame of a blue color. When the gas is passing through the tube, there are some little openings were air comes in and by the Bernoulli Effect; the combustion appears on top of the burner.
On top of the burner isa metallic square support for us to be able to place the beaker. When we place the beaker on top of the metallic support, heat can rapidly reach the water because metal is a good thermal conductor which means that it has molecular bonds in orderly arrangement letting the passage of heat. Considering that glass isn’t such a good insulator the heat will continue to the water. Even though, waterspends a period of time getting to its boiling point. This happens because when heat is being transfer, a small piece of energy is remained in the beaker and in the metallic support making the amount of heat that is going to reach the water to be less. When water gets to its boiling we place the 125 mL Erlenmeyer with the balloon on top of it. The water has a lot of energy so the particles go fasterand that is why we notice the presence of gas as bubbles. In this moment we turn off the passage of gas, turning off the flame. The transferring of heat is going to stop, so the exceed of heat in the water is going to be transferred into the 125 mL Erlenmeyer which is going to make the balloon to expand because the particles are going to go faster so the pressure is going to increase and also thevolume of the balloon as shown in the graphs above.
In this moment we place a piece of mask tape in a tension form (after the expansion). After this, we take out the 125 mL Erlenmeyer from the hot water and place it into cold water. The heat that was transferred for the balloon to expand will rapidly be transferred to the cold water for making a thermal equilibrium between both materials. Theballoon is going to be compressed and we notice it by seeing some wrinkles in the piece of mask tape. This happens because tape has properties of adhesion so it is always paste to the same piece of the balloon.
When we said that if the temperature increases, the pressure also increases and so does the volume, we are talking of macroscopic measurements because they doesn’t referred to one molecule,...