Worked examples: WACE Chemistry Data Book

Selected worked examples

1. Periodic table · molar mass

   Formula or reference: Add the atomic masses according to the subscripts in the formula.

   Units and conditions: Use g/mol for molar mass. Keep extra digits until the end.

   Worked example: Using C = 12.01 and O = 16.00 gives a CO₂ molar mass of 44.01 g/mol.

2. Electrochemistry · reading reduction potentials

   Formula or reference: E°cell = E°cathode − E°anode, using standard reduction potentials for both half-reactions.

   Units and conditions: Read both tabulated values in volts. Multiplying a half-equation leaves its potential unchanged.

   Worked example: For tabulated reduction potentials of +0.80 V and +0.34 V, the higher-potential half-cell acts as cathode and E°cell = +0.46 V.