4. This metal (X) displaces copper from copper sulphate solution but does not
displace zinc from zinc sulphate. From this we can tell that the order of reactivity
(most reactive first) is
a. zinc; copper; X
b. zinc; X ; copper
c. copper ; X ; zinc
d. X; zinc; copper;

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