(a(i))[1]
Which element makes up 21% of dry air?
(a(ii))[1]
Which element reacts rapidly with cold water to produce hydrogen?
(a(iii))[1]
Which element is in Group III of the Periodic Table?
(a(iv))[1]
Which element has atoms with a complete outer shell of electrons?
(a(v))[1]
Which element is a transition element?
(a(vi))[1]
Which element forms stable ions with a single positive charge?
(b)[4]
Fill in the table with the numbers of electrons, neutrons and protons for the nickel atom and oxide ion shown.