Question

how does a Litmus indicator work​

Answer 1

Answer:

Explanation:Blue litmus paper turns red under acidic conditions and red litmus paper turns blue under basic or alkaline conditions, with the color change occurring over the pH range 4.5–8.3 at 25 °C (77 °F). Neutral litmus paper is purple. Litmus can also be prepared as an aqueous solution that functions similarly.

Answer 2

Litmus indicator solution turns red in acidic solutions and blue in alkaline solutions. It turns purple in neutral solutions. Litmus paper is usually more reliable, and comes as red litmus paper and blue litmus paper.

Wet litmus paper can also be used to test for water-soluble gases that affect acidity or alkalinity; the gas dissolves in the water and the resulting solution colors the litmus paper. For instance, ammonia gas, which is alkaline, turn the red litmus paper blue.

Litmus (pH indicator)

below pH 4.5  above pH 8.3

4.5 ⇌ 8.3

Chemical reactions other than acid-base can also cause a color change to litmus paper. For instance, chlorine gas turns blue litmus paper white – the litmus dye is bleached, because of presence of hypochlorite ions. This reaction is irreversible, so the litmus is not acting as an indicator in this situation.