Answer to Question #208124 in General Chemistry for Hania

Question

The percentage of oxygen in air can be determined by the following experiment.

 

The gas syringe contains 50 cm3 of air. The large pile of copper is heated and the air is passed from one gas syringe to the other over the hot copper. The large pile of copper turns black. The gas is allowed to cool and its volume measured.

The small pile of copper is heated and the remaining gas passed over the hot copper.

The copper does not turn black. The fi nal volume of gas left in the apparatus is less than 50 cm3.

(i) Explain why the copper in the large pile

Answer 1

$4Cu + O_2\to 2Cu_2O$

The copper in the large pile turns black because it is oxidized.