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What belongs in each mystery box?

Every mystery box holds the same value. Make the two sides balance.

5 × ? + 666Equal values make a level balance.

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ScienceAges 16-18Chemistry: acids & bases
Question 1 of 4
Acids, bases & the pH scale

What weak organic acid is found naturally in lemons, limes and oranges?

Use the 0–14 pH scale, indicators and neutralisation reactions to classify acidic, neutral and alkaline solutions.

pH Scale: 0 (Acid) → 7 → 14 (Alkali) · Indicator Solution
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Science category

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