It’s a GAS!

Problems:1)What are the similarities and differences in carbon dioxide and oxygen gas?

2) How does the volume of gas in a balloon change as a) temperature increases b)temperature decreases?

3) How does the volume of a gas in a marshmallow change as a) pressure increases b) pressure decreases?

Hypothesis/Predictions:

1.What do you think will happen if a glowing ember interacts with oxygen?

2. What do you think will happen if a burning splint interacts with carbon

dioxide?

3. As temperature increases, the volume of gas in a balloon will ______

Because______.

4. As temperature decreases, the volume of gas in a balloon will ______

Because______.

5. As pressure increases, the volume of gas in a marshmallow will ______

Because______.

6. As pressure decreases, the volume of gas in a marshmallow will ______

Because______.

Investigate Science Standards: 3. Each of the more than 100 elements of matter has distinct properties and a distinct atomic structure. All forms of matter are composed of one or more of the elements. As a basis for understanding this concept: b. Students know that compounds are formed by combining two or more different elements and that compounds have properties that are different from their constituent elements. d. Students know the states of matter (solid, liquid, gas) depend on molecular motion. e. Students know that in solids the atoms are closely locked in position and can only vibrate; in liquids the atoms and molecules are more loosely connected and can collide with and move past one another; and in gases the atoms and molecules are free to move independently, colliding frequently.

Materials:

125 ml erylmeyer flask, 600 ml beaker, 50ml graduated cylinders, baking soda, yeast, hydrogen peroxide, vinegar, wooden splints, alcohol burners, wire rack, pot holders,goggles, balloon, water, ice, syringe, marshmallow.

Procedure:

Part 1:

  1. Add a TINY amount of baking soda to a clean flask.
  2. Add 10ml of vinegar to baking soda. Swirl.
  3. Quickly place a flaming splint into flask and bubbles. Do not touch the liquid!
  4. Observe what happens, as you try to put burning splint into bubbles.
  5. Record observations. What do you think the bubbles are and why?

Part 2:

  1. Add a TINY amount of yeast to a clean flask.
  2. Add 10ml of hydrogen peroxide to yeast. Swirl.
  3. Quickly light a splint, then BLOW it OUT. Do not touch the liquid!
  4. Pop bubbles with glowing ember.
  5. Observe what happens, as you try to put splint into bubbles.
  6. Record observations. What do you think the bubbles are and why?

Data:

Observations / What are the bubbles?
Part 1
Part 2

Part 3:

1. Pour 50ml of water into the 125 ml flask.

2. Fill the 600 ml beaker half way with ice.

3. Add approximately 200ml water to the beaker with ice.

4. Record 1ST observations: include a SKETCH and WRITTEN descriptions of the flask with the

water in it.

5. Light alcohol burner.

6. Do not put the balloon on yet.

7. Place the flask on top of the wire rack with flame.

8. Record 2ND observations for 3 minutes: include both a SKETCH and WRITTEN descriptions.

9. When instructed to do so (in about 3 minutes), CAREFULLY place the balloon on the mouth of

the flask.

10. Keep the burner on.

11. Record 3rd observations, but wait for the balloon to inflate before you do the observations.

12. Blow the burner out.

13. Carefully set the flask into the ice water bath.

14. Record 4th observation for 25 minutes: SKETCH and WRITTEN descriptions.

15. Clean up neatly and efficiently. Be sure all equipment is returned to its proper place.

Data:Observations for balloon and water

Written Description / Sketch
1st
2nd
3rd
4th

Part 4:

  1. Take a small syringe and pull out the plunger.
  2. Drop in a mini marshmallow, and push in the plunger just up to the point that the plunger barely touches the marshmallow.
  3. Tape the tip of the syringe or put your finger over the hole.
  4. Pull the plunger out. Write 1stobservations.
  5. Push plunger in. Write 2ndobservations.

Data: Observations for syringe and marshmallow

Written Description / Sketch
1st
2nd

Questions:

1. Which gas, O2 or CO2, is more plentiful in our atmosphere?

2. Air is a mixture of gases. Both the gases produced in this lab are pure substances. Which of the gases you will produce is a compound? Why?

3. Which gas do you think is used in fire extinguishers?

4. Explain what happens to the water vapor molecules:

A) as the temperature rises.

______

______

B) as the temperature decreases.

______

______

5. Explain how this lab demonstrates Charles’ Law. ______

______

______

Draw a picture from the lab that shows, as temperature increases, volume______. / Draw a picture from the lab that shows, as temperature decreases, volume ______.

6.Explain how this lab demonstrates Boyles’ Law.____________

______

Draw a picture from the lab that shows, as pressure increases, volume ______. / Draw a picture from the lab that shows, as pressure decreases, volume ______.

Conclusion: Short conclusion- answer problems refer to hypotheses.