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In an experiment to analyze a 200cm3 sample of air was treated with pyrogallic acid. This reduced its volume to 168cm3. Potassium hydroxide was then...

In an experiment to analyze a 200cm3 sample of air was treated with pyrogallic acid. This reduced its volume to 168cm3. Potassium hydroxide was then added and the volume of gas reduced further to 160cm3.

(a) What was the role of pyrogallic acid?

(b) What was the role of potassium hydroxide?

(c) Calculate the percentage of oxygen and percentage of carbon (iv) oxide in the sample

(d) Suggest the likely biological source of carbon (iv)oxide gas.
(e) State the behavior of external intercostal muscles during exhalation.

(f) Explain why smokers are more prone to respiratory tract infections than the non- smokers

Answers


Martin
(a) To absorb oxygen

(b) To absorb carbon (IV) oxide

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(d) Exhaled air

(e) External intercostal muscles relax

(f) Cigarette smoke inhibits action of cilia in the respiratory tract resulting to accumulation of dust particles, bacteria and mucus; bacteria invade cells of mucous membrane thus causing diseases /respiratory tract infections
marto answered the question on September 30, 2019 at 10:33

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