a) i) Boiling tube A;
Atmospheric air rushes in through tube R/. bubbles form in the lime water;
Lime water remains clear;
Boiling tube B;
Lime water rises in tube S
ii) Boiling tube A;
Lime water rises up the tube R;
b) Boiling tube B
Bubbles of air occur in the lime water
Lime water turns to white precipitate
c) Conclusion that can be drawn from the result
Exhaled air has more carbon (IV) oxide than inhaled air;
d) The purpose of boiling tube A
It is a control (for B); Experiment
sharon kalunda answered the question on September 16, 2019 at 11:16
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