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
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
state that and explain why isotopes of the same element have the same chemical properties
determine the electronic configuration of atoms and ions given the atomic or proton number and charge, using either of the following conventions: e.g. for Fe: \( 1s^2 2s^2 2p^6 3s^2 3p^6 3d^6 4s^2 \) (full electronic configuration) or \( [Ar] 3d^6 4s^2 \) (shortband electronic configuration)