How do you know whether co2 is present in something or not?

Answer 1

CO2 has a distinct smell, faint, but still distintict. Also, if you inhale it you will start to pant due to a lack of oxygen. That is how you can tell.

Ayraayra: acutally the "panting" or increased breathing rate is due to the build up of CO2 not because the lack of O2.

Answer 2

CO2 can be detected using various methods, such as gas sensors or chemical indicators that change color in the presence of CO2. Additionally, instruments like infrared spectrometers can analyze a sample to determine the presence of CO2 by measuring its absorption of specific wavelengths of light.