To Prepare Co2 Gas And Study Its Properties. | Grade Xi

APPARATUS REQUIRED

• Conical flask (250 ml)
• Delivery tube
• Test tube
• Lime water
• Candle
• Bunsen burner
• Spatula
• Hydrochloric acid (HCl)
• Calcium carbonate (CaCO3)

CHEMICAL REQUIRED

• Calcium carbonate (CaCO3)
• Hydrochloric acid (HCl)

THEORY

Carbon dioxide (CO2) is a colorless, odorless, and non-flammable gas. It is produced when carbon-containing compounds are burned in the presence of oxygen. CO2 is also produced by the respiration of living organisms.

The reaction between calcium carbonate (CaCO3) and hydrochloric acid (HCl) produces CO2 gas. The balanced chemical equation for this reaction is:

CaCO3(s) + 2HCl(aq) → CaCl2(aq) + CO2(g) + H2O(l)

PROCESS

1. Place a small amount of calcium carbonate (CaCO3) in a conical flask.
2. Add 10-15 mL of hydrochloric acid (HCl) to the conical flask.
3. Connect the conical flask to a delivery tube.
4. Place a test tube filled with lime water at the end of the delivery tube.
5. Light a candle and place it near the mouth of the test tube.
6. Heat the conical flask gently with a Bunsen burner.

OBSERVATIONS

• The reaction between calcium carbonate (CaCO3) and hydrochloric acid (HCl) produces a colorless, odorless gas.
• The gas bubbles through the lime water and turns it cloudy.
• The candle flame is extinguished when it is placed near the mouth of the test tube.

OBSERVATION TABLE

Observation	Explanation
Colorless, odorless gas produced	Carbon dioxide (CO2) gas is produced by the reaction between calcium carbonate (CaCO3) and hydrochloric acid (HCl).
Gas bubbles through lime water and turns it cloudy	Carbon dioxide (CO2) gas reacts with lime water (Ca(OH)2) to form calcium carbonate (CaCO3) and water (H2O). The calcium carbonate (CaCO3) precipitates out of solution, causing the lime water to turn cloudy.
Candle flame extinguished	Carbon dioxide (CO2) gas is a non-flammable gas. When the candle flame is placed near the mouth of the test tube, the carbon dioxide (CO2) gas extinguishes the flame.

CALCULATION

The amount of carbon dioxide (CO2) gas produced can be calculated using the following formula:

Mass of CO2 (g) = Mass of CaCO3 (g) × 0.44

RESULTS

The experiment showed that carbon dioxide (CO2) gas is produced when calcium carbonate (CaCO3) and hydrochloric acid (HCl) react. Carbon dioxide (CO2) gas is a colorless, odorless, and non-flammable gas. It reacts with lime water to form calcium carbonate (CaCO3) and water (H2O). Carbon dioxide (CO2) gas extinguishes a candle flame.

PRECAUTIONS

• Wear gloves and safety goggles when conducting this experiment.
• Do not heat the conical flask too strongly.
• Do not inhale the carbon dioxide (CO2) gas.