Chemistry Questions

Atoms of the same element can have same atomic number and number of electrons since, the atomic number is the number of protons and the number of protons and eectrons are the same in an element.

Hence, the atoms of the same element may differ in their atomic mass since it depends on the number of neutrons it holds and such atoms are called isotopes.

When exposed to certain frequencies of radiation, such as radio waves, the subatomic particles called electrons that orbit an atom's nucleus will "jump" back and forth between energy states. Clocks based on this jumping within atoms can therefore provide an extremely precise way to count seconds.It is no surprise then that the international standard for the length of one second is based on atoms. Since 1967, the official definition of a second is 9,192,631,770 cycles of the radiation that gets an atom of the element called caesium to vibrate between two energy states.