(a(i))[2]
Complete the table by estimating the boiling point of rubidium and the atomic radius of potassium.
(a(ii))[1]
Describe how the melting point of the Group I elements changes down the group.
(a(iii))[2]
Deduce the physical state of potassium at $60\,^{\circ}\text{C}$. Give a reason for your answer.
(b(i))[1]
Define proton number.
(b(ii))[1]
State one industrial use of radioactive isotopes.
(c(i))[2]
Balance this reaction equation. $\text{Fe}_2\text{O}_3 + 3\text{NaH} \rightarrow \ldots\text{Fe} + \ldots\text{NaOH}$
(c(ii))[1]
Explain how this equation shows that iron(III) oxide is reduced.