Helium
He
Helium
The atomic number is 2 and the mass number is 4. Helium is in period 1 group 18. It is part of the noble gases. It is a nonmetal gas.
Balloons.
Helium is a very light element. When you put it inside a balloon it tries to float.
The Sun
Helium is in the Sun. If you were to look at everything in the sun you would discover large amounts of helium. The Sun is a really big ball of gases and all those gases are on fire. One of the results of that fire is helium.
Rocket Fuel
Whenever you see NASA shoot a rocket into space they are using helium. When they launch rockets into space, they sometimes use helium to cool the engines.