Multiple choice

Which of the following options turn red litmus into blue?

  1. Acids

  2. Bases

  3. Salts

  4. None of these

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Bases (alkaline substances) turn red litmus paper blue, which is a classic test for identifying basic solutions. Acids turn blue litmus red, while salts generally don't change the color of litmus paper. This color change occurs due to the pH difference between acidic and basic solutions.