11.   A nitro group is a molecular fragment consisting of a nitrogen atom bonded to two oxygen atoms.

12.   But when a single hydrogen bond breaks, an oxygen atom can bind to the silicon, starting a chain reaction that rips through the structure like wildfire.

13.   Close to the ground, ozone, a molecule consisting of three oxygen atoms, forms a large and unhealthy component of smog.

14.   Fearful that ordinary mouthwashes were drying out the palates of the stars, Saldamando brewed up a compound with a main ingredient that contains extra oxygen atoms.

15.   In their latest looks, they saw no signs of lightning, but did see the faint glow of excited oxygen atoms on the night side of Venus.

16.   Oxygen VI is an oxygen atom that has five of its eight electrons stripped away.

17.   Ozone molecules are composed of three oxygen atoms, rather than the two atoms oxygen molecules usually contain.

18.   One of the worst offenders, she said, is the oxygen molecule, which is split by ultraviolet light into a pair of oxygen atoms that attack everything.

19.   Researchers at University of Wisconsin and Princeton diffused oxygen atoms into thin films of magnesium diboride.

20.   That was significant because chemists can attach other atoms to the oxygen atoms, leading to more complex products.