Introduction

Natural gas is a major energy source used to heat homes, generate electricity, and fuel vehicles. It is mostly composed of methane, a potent greenhouse gas. While combustion of natural gas generates less emissions than coal and oil, natural gas poses environmental challenges in its extraction and use. This lab utilizes the student activity station format to help students explore the science of natural gas from its formation to its combustion. 

Student Objectives

Students will be able to

• Simulate and analyze methane production using biological processes, and explain how this relates to natural gas formation in landfills and biogas systems.
• Model and evaluate the process of hydraulic fracturing, identifying how permeability and rock layers influence extraction and potential environmental risks.
• Measure and compare temperature changes in water to evaluate relative heat transfer from different fuels in a combustion simulation.
• Construct a life cycle concept map of natural gas, illustrating key stages from formation to use, and identifying both environmental benefits and challenges at each stage.

Materials

• Student Handout (per student)

Teacher Set Up

Station 1: Methane Formation and Capture Simulation

To set this station up, teachers will set up the sugar, teaspoon, yeast, and balloons on the side. Depending on the layout of the classroom, students can get warm water from classroom sinks (if available) or have a jug of warm water available on the table. Since funnels, lab flasks, rulers, and timers are reusable, just having 2-3 per station will be sufficient. 
(Note: More than one group can be at this station at once, if space allows.)

Procedure 
Included in Student Handout, along with a Data Table for recording observations/Analysis Questions.

1. Add 1 tsp of sugar and 1 packet (or 2 tsp) of yeast to a flask.
2. With the funnel, add warm water to fill one-third of the flask and swirl gently.
3. Place a balloon tightly over the flask opening.
4. Observe for 15 minutes, measuring the diameter with the ruler or measuring tape every 5 minutes, recording your measurements in the Data Table. 
5. Record any additional observations (color, smell, bubbles, etc.) on the Data Table. 
6. Tidy up the station area, rinse out the bottle, throw the balloon away, and return all materials to the proper place. 

Station 2: Hydraulic Fracturing and Permeability Simulation

To set up this station, teachers will lay out the clay, sponges, and sand. Colored water can be prepared beforehand (food coloring and water) and made available for students in a jug. Since containers and syringes are reusable, 2-3 per station will be sufficient. 
(Note: More than one group can be at this station at once, if space allows.)

Procedure
Included in Student Handout, along with a Data Table for recording observations/Analysis Questions.

1. Create layers in your clear container. Start (at the bottom) with an approximately one inch layer of sand, representing the gas reservoir.
2. Next, add an approximately one inch layer of clay, representing cap rock. 
3. Last, add an approximately one inch layer of sponge, representing porous rock. 
4. Fill the syringe with 20 mL of colored water. 
5. Inject the colored water into the bottom sand layer, by inserting the syringe along the side of the container. 
6. Observe how and where the fluid travels, and record your observations in the Data Table. 
7. Tidy up the station area, replace layers that are reusable and throw away those that are not (e.g. sand), rinse out the container, and return all materials to the proper place.

Station 3: Combustion Energy and Emissions Simulation

Since this station involves open flame and needs extremely careful monitoring, the teacher may decide to do this as a demonstration instead of setting it up as a student activity station. 

Safety Reminder:
Only one group should conduct this experiment at a time due to the use of open flames and reactive substances. All students must wear safety goggles and use tongs or heat-resistant gloves when handling hot or chemical materials.

Instructor Lab Setup Instructions
Set up the materials in three distinct supply areas to organize the equipment efficiently:

Supply Area A – Heat Sources:

• Natural gas burner
• Large candle
• Lighter
• Ethanol gel can

Supply Area B – Safety Equipment:

• Safety goggles
• Heat-resistant gloves
• Tripod stand
• Beaker tongs

Supply Area C – Testing Materials:

• Three small cans
• Jug of water (if a nearby sink is unavailable)
• Thermometer
• Small beaker

Layout Recommendation:
Arrange the supply areas along a counter, bench, or side table in sequence (A → B → C), allowing for clear access and separation between categories. These areas are for instructor preparation and student access during guided portions, not part of the student rotation cycle.

Procedure
Included in Student Handout, along with a Data Table for recording observations/Analysis Questions.

1. Prepare three identical metal cans, each containing 50 mL of water.
2. Record the initial temperature using a thermometer and record that data on the Data Table. 
3. Set the tripod and candle in the middle of your work area. 
4. Place the can of water on the tripod above the candle. Make sure that the can is secure.  
5. Light the candle and immediately start a timer. Allow the water to heat for exactly 3 minutes.
6. At the 3-minute mark, extinguish the flame. Measure temperature immediately after and record the final water temperature on the Data Table. 
7. Record any additional observations, such as soot, smell, smoke, etc. 
8. Let the metal can on the tripod cool for a minute. Then, using the beaker tongs, carefully remove the can and place it in a safe location where it can cool.
9. Carefully remove the candle and replace it with the ethanol gel can. 
10. Place the second can of water on the tripod above the ethanol gel can. 
11. Light the ethanol gel can and repeat the procedure once again, filling out your data table. 
12. To extinguish the ethanol gel flame, use the beaker tongs to secure the lid over the can.
13. Remove the ethanol gel can with the beaker tongs and place it in a safe location where it can cool.
14. Place the natural gas burner beneath the tripod. Place the third can of water on the tripod.
15. Turn on the natural gas burner, adjust to a consistent high flame setting, and repeat the 3-minute heating procedure.
16. Tidy up the station area, empty and rinse containers (use beaker tongs to cool down metal cans with cold water, so it’s safe for the next group to use), and return all materials to their proper place.

Wrap-Up Activity

Included in the Student Handout, students will draw a concept map showing the lifecycle of natural gas.
Formation → Extraction → Combustion → Use → Environmental Impact
For each section, students will add a description, as well as notes concerning benefits and impacts at each stage, when applicable. 

Answer Key

The Student Guide contains the Exploring Natural Gas Lab – Student Questions.
Station 1: Analysis Questions Answer Key
Question 1: The balloon inflates due to the production of carbon dioxide gas as it breaks down the sugar during anaerobic respiration (fermentation). The gas collects in the balloon, causing it to expand. 
Question 2: This simulates microbial digestion in landfills or biodigesters, where microbes decompose organic waste and release gas like methane and carbon dioxide. Similarities include the microbial decomposition of organic material, and the production of gas that can be captured. Differences include that the yeast model mainly produces carbon dioxide, while real microbial digestion produces a mix of methane and carbon dioxide. Landfill microbes also work in low-oxygen environments, and take longer.

Station 2: Analysis Questions Answer Key
Question 1: The syringe injecting colored water represents high-pressure fluid being injected into rock layers. Similarities include the fracturing that forms in rock layers, and how the fluid moves through the porous material once fracture occurs. Differences include that real hydraulic fracturing uses extreme pressures and actual rock deep underground. 
Question 2: Possible environmental risks include contamination if groundwater fluids leak through cracked layers, induced seismicity (small earthquakes), wastewater disposal and surface spills, and habitat disruption from drilling activity. 

Station 3: Analysis Questions Answer Key
Question 1: Answers will vary.
Question 2: Answers will vary.

Wrap Up Activity (Example Responses) Answer Key
Formation: Organic material is buried and compressed over millions of years under heat and pressure, forming natural gas. One benefit is the formation of an abundant energy resource. One impact is that this energy source is non-renewable and could leak methane during extraction. 
Extraction: Drilling and hydraulic fracturing release natural gas from underground reservoirs. Benefits include the high energy return and job creation. Impacts include groundwater contamination risk and habitat disruption. 
Combustion: Natural gas is burned for heating, electricity, and transportation. Benefits include high efficiency and fewer particulates than coal or oil combustion. Impacts include carbon dioxide emissions. 
Use: Energy produced with natural gas is used in power plants, homes, factories, and vehicles. One benefit of natural gas energy is that it has less emissions than other fossil fuels. One impact is the high cost of infrastructure investment. 
Environmental Impact: Greenhouse gas emissions, along with risk of methane leaks, and water and land contamination. One benefit of natural gas is that it serves as a “bridge fuel” for transition between fossil fuels and lower emission energy sources. However, it still contributes to air pollution with carbon dioxide emission.

Conclusion Questions Answer Key
Question 1: High energy output, has fewer emissions than coal or oil, produces less soot and fewer particulates, is reliable and widely available, useful in many ways including heating, electricity production, and as a transportation fuel.
Question 2: Emits carbon dioxide when burned, risk of methane leaks (methane is a powerful greenhouse gas), risk of groundwater contamination from hydraulic fracturing, habitat and landscape disruption from extraction.
Question 3: Improved drilling techniques reduce leaks and spills; methane capture and leak detection technologies; research into carbon capture and storage; transitioning to lower emission energy sources; monitoring regulations to protect water and air quality.