The apparatus shown below was used to investigate the effect of carbon (II) oxide on copper (II) oxide.

(a) State the observation that was made in the combustion tube at the end of the experiment.
(b) Write an equation for the reaction that took place in the combustion tube.
(c) Why is it necessary to burn the gas coming out of tube K?

Answer:

a)- Copper (II) oxide turned from black to brown.
b)#CuO(s)+CO(g)rightarrowCu(s)+CO_2(g)#
c)- It is poisonous hence should not be released into the air.

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