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.
World Rare Disease Day 2016. World Rare Disease Day is an annual observance held on the last day of February to raise awareness for rare diseases and improve access to treatments and medical representation for individuals with rare diseases and their families. The 9th annual World Rare Disease Day will be held on Monday, February 29, 2016 (the rarest day of the year)! On this day, various activities take place in the United States, Europe, Russia, Japan and elsewhere around the world.