Answer :

The first vertical row of elements are all alkali metals with the exception of hydrogen which is a transition metal. The elements are: Hydrogen(H) with an atomic number of 1 Lithium(Li) with an atomic number of 3 Sodium(Na) with an atomic number 11 Potassium(k) with an atomic number 19 Rubium(Rb) with an atomic number of 37 Cesium(Cs) with an atomic number of 55 Fracium(Fr) with an atomic number of 87