How do scientists know when water first appeared on Earth? by Lloyd Wood https://padlet.com/1164403/ps7va1km5xoa 7.4 Honors Assignment en-us 2017-10-21 16:44:18 UTC 2017-10-22 15:21:09 UTC hello@padlet.com Water 1164403 https://padlet.com/1164403/ps7va1km5xoa/wish/199292675 Water is made up of 2 hydrogen atoms and 1 oxygen atom, also known as H2O.]]> 2017-10-21 19:00:28 UTC https://padlet.com/1164403/ps7va1km5xoa/wish/199292675 Hydrogen and Oxygen 1164403 https://padlet.com/1164403/ps7va1km5xoa/wish/199292761 Hydrogen was one of, if not the first element on the scene after the Big Bang, 13.7 billion years ago. Oxygen appeared several hundred million years later, after star began to form. The tremendous pressure on the center of the planets created oxygen and other elements. When a star exploded, also known as a supernova, the massive explosions spread these elements across the universe.
Source: https://www.youtube.com/watch?v=RwtO04EXgUE]]> 2017-10-21 19:01:46 UTC https://padlet.com/1164403/ps7va1km5xoa/wish/199292761