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.
United Kingdom: Everyone has a right to the best treatment and care ... by Mena Report. Observed annually on the last day of February, Rare Disease Day is coordinated at the international level by the European Organisation for. (EURORDIS) and by National Alliances and Patient Organizations at the national level.