Which atom will tend to lose rather than gain 1 or more valence electrons when forming an ion?

The atom which has less the 4 valence electron.

If a hydrogen atom is neutral, it must also have  one electron. an oxygen atom (o) has an atomic number of eight (8). this means a neutral oxygen atom has eight protons and eight electrons. the element actium (ac) has an atomic number of 89, so it has 89 protons and 89 electrons in a neutral atom