Earth’s core could contain helium from the early solar system. The noble gas tucks into gaps in iron crystals under high pressure and temperature.

But from a helium perspective, it's been a very steep learning curve. Understanding what is the end application for this. One ...

If an atom has 2 protons, that’s an atom of the element helium. If it has 7 protons, that’s nitrogen. But the logic of the periodic table also relies upon the number and organisation of electr ...

So how has the periodic table been put together ... Any letters that follow will be lower case letters, for example, helium is He. Some element symbols are simple. For example, oxygen is O.Others ...

For example, a helium atom has an atomic mass of 4, but an atomic number (or positive charge) of 2. Since electrons have almost no mass, it seemed that something besides the protons in the nucleus ...