What was the significance of science and the world as we know it today in regards to discovering oxygen?

This flow chart shows the amount of energy that is emitted by each type of light. ultraviolet > blue light > yellow light > red light (maximum energy) (minimum energy) in an experiment, shining which type of light on a strip of metal would be least likely to produce the photoelectric effect? ultraviolet light dim blue light bright red light bright yellow light

An atom of lithium-7 has an equal number of(1) electrons and neutrons(2) electrons and protons(3) positrons and neutrons(4) positrons and protons

How many moles of no2 will form when 3.3 moles of cu are reacted with excess hno3?