Oxygen is perhaps the most important atom on Earth. It is responsible for life as we know it, and it is the most abundant atom in our planet. There are
more oxygen atoms on Earth than all the other elements' atoms combined.
It was discovered as an atom by Antoine Lavoisier in 1777.The image shows
the Bohr atom model for Oxygen. Which of the following electronic
transitions in the oxygen atom will result in light emission?

b

explanation:

mitosis

chemical changes occur when a substance combines with another to form a new substance, called chemical synthesis or, alternatively, chemical decomposition into two or more different substances. these processes are called chemical reactions and, in general, are not reversible except by further chemical reactions. some reactions produce heat and are called exothermic reactions and others may require heat to enable the reaction to occur, which are called endothermic reactions. understanding chemical changes is a major part of the science of chemistry.