Exploding some myths
Declan Fleming investigates what’s really going on when alkali metals hit water
Pause to answer this question: why does sodium explode in water but lithium doesn’t?
If your answer hinges on comparing ionisation energies, the amount of energy or the volume of hydrogen released in both reactions you would be wrong (particularly for the latter two).
Sometimes we get so focused on the concepts we want to teach that we don’t stop to wonder if we really understand what we’re demonstrating. These are the perfect conditions for the seeds of ‘general ignorance’ to germinate.
Declan Fleming expounds the energetics argument and the surface area argument to investigate what’s really going on when alkali metals hit water.
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