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
Describe relative atomic mass, \( A_r \), as the average mass of the isotopes of an element compared to 1/12th of the mass of an atom of \( ^{12}C \)
Calculate the relative atomic mass of an element from the relative masses and abundances of its isotopes
Use the relationship amount of substance (mol) = mass (g) / molar mass (g/mol) to calculate: (a) amount of substance (b) mass (c) molar mass (d) relative atomic mass or relative molecular/formula mass (e) number of particles, using the value of the Avogadro constant