What is the atomic number for krypton? Krypton: Krypton is one of the rarest elements on Earth. It was discovered on May 20, 1989, when Sir William Ramsay and Morris M. Travers boiled away liquified air to better study its chemical composition. Answer and Explanation: Become a Study.com...
It has six protons, six electrons, and six neutrons, so its atomic number is 6 and its relative atomic mass is 12. But there's also another form of carbon called carbon-14, with six protons, six electrons, and eight neutrons. It still has an atomic number of six, but its relative ...