The difference is that technetium is radioactive.
the thing that makes elements different is the fact that they all have different amount of protons, electrons and neutrons. They all, also, have different mass #'s.
The number of protons in the nucleus or the number of electrons surrounding the nucleus. This number is also called atomic number of the element.
two or more different elements
Its made from different elements
The number of protons.
atom and elements are different because one atom makes an element and a element is a pure substance and a atom is a basic particle
two or more different elements
istopes have different numbers of neutrons and most of their elements have several istopes
The atoms of each element have a number of protons that is unique to each element. The number of protons makes one atom different from another.
their internal structure makes them behave in a similar way.
They don't have the same elements that make them. Hope it helped. =)
Oxygen makes up 20.95% of the air surrounding Earth (that is almost 25%).