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Question
A beaker of concentrated hydrochloric acid has a pH of 1. What colour will full range universal indicator turn if it is added to this beaker? Is it a strong or a weak acid?
Solution
HCl, with a pH of 1, imparts a red colour when treated with a universal indicator. As the pH value decreases from 7, the acidity increases, as there is an increase in the concentration of hydrogen ions (H+). So, the given acid is very strong.
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