Older MCQs might not have the typical A, B, C,
D
choices. They
have choices 1, 2, 3, and a combination of them is the answer. Below is the key that maps such
combinations to the answer.
A
1, 2 and 3 are correct
B
1 and 2 only are correct
C
2 and 3 only are correct
D
1 only is correct
write formulas of ionic compounds from ionic charges and oxidation numbers (shown by a Roman numeral), including: (a) the prediction of ionic charge from the position of an element in the Periodic Table (b) recall of the names and formulas for the following ions: \(NO_3^-\), \(CO_3^{2-}\), \(SO_4^{2-}\), \(OH^-\), \(NH_4^+\), \(Zn^{2+}\), \(Ag^+\), \(HCO_3^-\), \(PO_4^{3-}\)
determine the numbers of protons, neutrons and electrons present in both atoms and ions given atomic or proton number, mass or nucleon number and charge
describe, explain, and write equations for, the acid/base behaviour of the oxides Na₂O, MgO, Al₂O₃, P₄O₁₀, SO₂ and SO₃ and the hydroxides NaOH, Mg(OH)₂ and Al(OH)₃ including, where relevant, amphoteric behaviour in reactions with acids and bases (sodium hydroxide only)
