The group 1 elements are the most electropositive elements in the periodic table.
Electropositive nature of the elements is defined as the ability of metals to lose electrons in order to gain stability. They form positive ions. The atomic radii of group 1 elements are large, hence the nuclear attraction will be less on the electrons. As a result, the elements can easily lose electrons. Hence, elements of group 1 of the periodic table are the most electropositive as compared to the rest of the elements.