0

Guest

Courses New

what is the compound involved in changing of blue litmus to red litmus paper in acids

what is the compound involved in changing of blue litmus to red litmus paper in acids
 

Grade:6

1 Answers

Abhishek Kumar
askIITians Faculty 255 Points
9 years ago
Litmus is a natural dye made from small plants called, "lichens". These plants are of several varieties and grow in abundance in the Netherlands. When lichen called Rocella Tincotoria is allowed to react with ammonia, potassium carbonate and lime it gives a blue-color material, which is used as the coloring matter for paper. The paper is dipped into it and dried. This is what is known as blue litmus paper and used to test acids.

Orchil or cudbear is a red dye obtained from another species of lichens. This is used to make red litmus paper Alkannet or alkanna is another dye obtained from root of the plant Alkanna Tinctoria. The coloring ingredient, alkannin is soluble in alcohol, benzene and ether. When white paper is impregnated with an alcohol solution of alkannet, it becomes red. This paper is turned to blue shade by alkalis.

Think You Can Provide A Better Answer ?

Other Related Questions on Organic Chemistry

View all Questions »

ASK QUESTION

Get your questions answered by the expert for free

Answer and earn gift vouchers

Win Gift vouchers upto Rs 500/-

View courses by askIITians

Design classes One-on-One in your own way with Top IITians/Medical Professionals

Click Here Know More

Complete Self Study Package designed by Industry Leading Experts

Click Here Know More

Live 1-1 coding classes to unleash the Creator in your Child

Click Here Know More

a Complete All-in-One Study package Fully Loaded inside a Tablet!

Click Here Know More