A student adds a few drops of the universal indicator solution to a dilute solution of sodium hydrogencarbonate taken in a test-tube. Which of the following colour would he observe?
(1) blue(2) green(3) mustard(4) yellow
"\n
Correct answer: (1) blue
Explanation: Universal indicator is used to check the pH of unknown solutions. Bases give blue colour, as sodium hydrogencarbonate is a base, so it will turn the colourless solution blue.
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