Answer the following question given this paragraph: 

Following hydrogen is the noble gas helium, which has an atomic number of 2. The helium atom contains two protons and two electrons. The first electron has the same four quantum numbers as the hydrogen atom electron (n = 1, l = 0, ml = 0, m s = + 1 ). The second electron also goes into the 1s orbital and fills that orbital. The second electron 2 has the same n, l, and ml quantum numbers, but must have the opposite spin quantum number, m s = − 1 . This is in 2 accord with the Pauli exclusion principle: No two electrons in the same atom can have the same set of four quantum numbers. For orbital diagrams, this means two arrows go in each box (representing two electrons in each orbital).


Q: What noble gas follows hydrogen on the periodic table?

 Choices:

- nitrogen

- oxygen

- halogen

- helium

A:
helium
