How to Test for CO2 Gas
- 1). Invert a test tube so that the open end is facing down.
- 2). Release the gas you want to test from its container into the test tube. Keep the test tube inverted so that the gas does not escape.
- 3). Light a splint with matches or a lighter. Place the lit end of the splint in the test tube. The splint will immediately extinguish if carbon dioxide is present in the gas.
- 4). Place moist blue litmus paper in the test tube. The litmus paper will turn red if carbon dioxide is present in the gas.
- 5). Place moist universal indicator paper in the test tube. The universal indicator paper will turn orange if carbon dioxide is present in the gas.
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