Whereas blue litmus papers turn red when encounter with an acidic solution. The color change of litmus papers is taking place over p H range 4.5-8.3 at 25 °C.• Litmus papers give only two colors, either red or blue based on the p H of the solution. You probably think of acid as a dangerous substance. Generally, the p H value of acids ranges from zero to six. Bases also dissociate in the water like acids, but instead of producing H they produce OH- i.e. Alkalis become less alkaline when mixed with an acid. Some examples are caustic soda or sodium hydroxide, calcium hydroxide or limewater, borax.Litmus papers can be used by anyone without any expertise knowledge. Strong acids like HCl, HNOCOOH partially dissociate and give fewer amounts of protons. This color change is relevant to the p H of the solution.They only have to know which color is relevant to acidic and basic p H value. An acid with p H 1 is said to be very strong, and as the p H value increases, acidity is decreased. As the basicity increases, p H value will also increase and strong bases will have p H value 14. Sometimes the colors are not so contrasting, so it is bit difficult to determine the p H range.It allows quick tests of acidity and alkalinity for laboratory chemicals as well as foods and household products.Although electronic p H meters deliver more precise results, litmus paper is convenient, practical and well-suited for grade-school experiments as well as university and commercial labs. How do you determine if a substance is acidic or basic? Acids lose their acidity when combined with alkalis. Insects like bees, ants, etc have formic acid in their stings. The following are the properties of acids : Bases are substances that substances that are slippery to touch when in aqueous form. They also change the color of red litmus paper to blue. For example, Ammonium Hydroxide, Calcium Hydroxide, etc. However, there are a few food items that are basic in nature. All acids change the color of blue litmus paper to red. Lactic acid is found in milk and other dairy products.But from p H papers, the p H range of the solution can be determined.• So p H papers give more precise readings than litmus papers.