(a)(i) For M, n = 3. Substituting into 2n\(^2\), 2 x 3 x 3 = 18 is obtained.
(ii)
| Befor Combination | after Combination |
| Sodium 1s\(^2\)2s\(^2\)2p\(^6\)3s\(^1\) (Na)Fluorine 1s\(^2\)2s\(^{2}\)2p\(^5\) (F) | s\(^2\)2s\(^2\)2p\(^6\)(Na\(^+\))1s\(^2\)2s\(^2\)2p\(^6\)(F\(^-\)) |
(iii) (1) High melting and high boiling points.
(2) Conduction of electricity in solution
(3) Solubility in water
(b) 4Na + O\(_2\) -> 2Na\(_2\)O
Na\(_2\)O + H\(_2\)O -> 2NaOH
(c) Place 100cm\(^3\) of each (or equal volumes) in separate identical beakers and connect as shown in the diagram below.
Record the ammeter reading using one solution as the test solution. Using one solution as the test solution, connect again as shown in the diagram and take the reading. The higher reading indicates the electrolyte which has the higher conductance.
