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.
Celebrated on April 22nd, Earth Day has over a billion participants around the world. Individuals, businesses, schools and governments commemorate what has been achieved and discuss what remains to be done to protect Earth. And even better news - over the years, Earth Day has evolved into Earth Week and Earth Month.