Biogas is made from natural organic waste. A from four student set –up the apparatus below to investigate the composition of the gas. He passed...

Biogas is made from natural organic waste. A from four student set –up the apparatus below to investigate the composition of the gas. He passed it over heated copper (II) oxide. After that he obtained two products. One was cooled in a boiling tube while the other was collected using a syringe.


(a) What is the function of calcium oxide
(b) Name product
i) P
ii) Y
(c) Give the two observations made in tube X
(d) i) Name the type of reaction taking place in tube X
ii) Write the equation for the reaction above in (d)(i)
(e) What elements are present in biogas
(f) Explain why one tube in boiling tube Q is longer than the other

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(a) to dry the biogas

(b) P – water

Y – CO₂

(c) – black substance turns brown
- colourless liquid formed on cooler parts of tube X


(d) (i) Reduction

(ii) 4Cu O_(s) + CH_4(g)---->4Cu_(s) +CO_2(g) + 2H₂O_(l)

(e) Carbon, Hydrogen

(f) - to allow product P to condense
- Also for product Y to be collected by syringe.

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maurice.mutuku answered the question on September 23, 2019 at 10:00

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