Question

Acids turn blue litmus to ______

Answer 1

Hint: Litmus is a water-soluble combination of several lichen-derived colours. It is frequently absorbed into filter paper to make one of the first kinds of pH indicator, which is used to evaluate the acidity of materials. Litmus can be found in a variety of lichen species. Roccella tinctoria (South American) and Roccella fuciformis (European) are used to make the dyes (Angola and Madagascar).

Complete answer:
Acids cause litmus to become blue. When you put blue litmus paper in an acidic solution, it becomes red. When put in a basic or neutral substance, however, it will remain blue. The litmus paper may be used to determine the acidity or alkalinity of a solution. Where the pH level is below 4.5, the blue paper becomes red under acidic circumstances. The red paper, on the other hand, does not change colour in alkaline circumstances (pH more than 8.3). The colour of blue litmus does not change in alkaline circumstances, whereas the colour of red litmus does not change in acidic settings.
Litmus is mostly used to determine if a solution is acidic or basic. The colour shift occurs throughout the pH range 4.5–8.3 at 25 °C (77 °F), with light blue litmus paper turning red under acidic conditions and red litmus paper turning blue under basic or alkaline settings. Purple litmus paper is neutral. Litmus may also be made into an aqueous solution that works in the same way. The solution is red under acidic circumstances and blue in alkaline situations. Water-soluble gases that change acidity or basicity can also be tested using wet litmus paper; the gas dissolves in the water and the resultant solution colours the litmus paper.

Note:
Litmus paper can change colour due to chemical processes other than acid–base. Chlorine gas, for example, bleaches blue litmus paper by bleaching the litmus dye due to the presence of hypochlorite ions. Because this reaction is irreversible, the litmus cannot be used as an indication in this case.