nhận biết khí cacbon đioxit có trong hơi ta thở ra bằng cách nào

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Đáp án:

Giải thích các bước giải: thổi vào lửa mà tắt thì đó là CO2( do CO2 không duy trì sự cháy)

Đáp án: lấy ống hút và thổi vào lọ nước vôi trong ( Ca(OH)2) nếu nước vôi trong đục thì chứng tỏ ta có thở ra khí co2.

CO2 + Ca(OH)2 >> CaCO3 +H2O

Giải thích các bước giải:

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