Metal Carbonates and Acid

When a metal carbonate reacts with an acid it will form a salt, carbon dioxide, and water. Carbon dioxide is a gas and can be seen as bubbles as the reaction proceeds.

Metal carbonate + Acid ------------> Salt + Carbon dioxide + water

Aim: To show that carbon dioxide gas is produced when a metal carbonate reacts with the acid
Equipment: Two boiling tubes, delivery tube, and bung, Bunsen burner, test tube rack, wooden splint, a bottle of acid, small amount of metal carbonate, test tube tongs, safety glasses.
Method:
1. Light your bunsen burner.
2. Add a pea-sized amount of metal carbonate into one of the boiling tubes.
3. Place the boiling tube into a test tube rack. Ensure you have the bung and delivery tube ready
4. Add 5mL of acid to the boiling tube and quickly insert the bung and delivery tube into the mouth of the boiling tube
5. Holding the other boiling tube with your tongs, capture the gas produced as shown in the diagram below.

6. When you think the tube is full, your lab partner should light a wooden splint

7. Carefully remove the boiling tube from under the delivery tube, taking care to keep it facing upright.
8. Insert the burning splint into the burning mouth of the test tube.

Observations: When doing the experiment many gas bubbles were being formed in the test tube, and when we put the lit splint in, the flame went out.

Discussion:
- After getting the equipment, we then put in the 2mL of Hydrochloric acid and the Metal carbonate into the conical flask and quickly trapping the air with the bung that is connected to the delivery tube, and on other end of the tube we put it in a test tube where it can capture the gas. When we thought we captured enough gas, my partner lit a wooden splint on fire and placed it where the mouth of the test tube was. What happened was the flame went out and by this happening we now know that carbon dioxide was being present.

Another way we could do to find out if carbon dioxide was present was, In a test tube we put lime-water into it and we put the same things (Hydrochrolic acid & Metal Carbonate) into the conical flask and after we added these in, we quickly trapped it with the bung and the delivery tube, and at the end of the delivery tube we placed it into the lime-water. After holding it there for a while we notice that the lime-water was getting cloudy, and by this after effect towards the lime-water we could see that carbon dioxide was present.