Lewis O’Shaughnessy
Nottingham, UK
The exact volume required will depend on what is being washed out of the jar – vinegar is easier to remove than jam, which, in turn, is easier than peanut butter. But, if the aim is to reduce the amount of water used, an easy method is to do several repeat washes, each with less water, rather than a single wash with a larger volume. Two washes of 100 millilitres are more effective than one wash of 200 ml. Chemists use this approach regularly when washing reaction products, and also use a similar approach of “washing” the air with nitrogen to remove oxygen from a reaction vessel.
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