Is CO2 a good gas or bad gas?

Answer 1

CO2 is bad in the sense that it is toxic to animal life and is believed to be largely responsible for global warming.

CO2 is good in the sense that plants can't live without it.

Answer 2

CO2 is a natural component of the Earth's atmosphere and is essential for plant growth through photosynthesis. However, an excess of CO2 due to human activities like burning fossil fuels is a major contributor to climate change and global warming. So, while CO2 itself is not inherently "good" or "bad," its overabundance due to human activities poses significant environmental challenges.