Oxygen in the air. The percentage of oxygen in the air can be measured by passing a known volume of air over hot copper, and measuring the decrease in volume as the oxygen reacts with it. Here are the equations for this reaction: copper + oxygen â copper oxide. 2Cu + O2 â 2CuO.
Get ready - World Backup is March 31st! About World Backup Day is a day for people to learn about the increasing role of data in our lives and the importance of regular backups.
April 22nd-Earth Day-Earth Day is celebrated every April 22nd. The purpose of Earth day is to raise awareness and an appreciation for the Earth and all its natural resources. April 23rd-William Shakespeare 's Birthday-He was born on April 23, 1616. One of his most famous pieces of work was Romeo and Juliet.