Why does dry hcl gas not change the colour of dry litmus paper

Because the HCl gas does not dissociate to give up H+ and Cl- ions. But, in aqueous solutions HCl does dissociate and exist in ionic form. In solution there is an equilibrium going on between the ionized and unionized form of the litmus indicator molecules. I.e. a loss of or gain on H+. It is this that causes the litmus to change colour depending on the H+ & -OH concentration in solution. But, again, this does not happen in dry environment. Remember an acid increases the hydronium ion concentration of solution. pH = -log[H30+]. Why a dry blue litmus paper is not affected by hydrogen chloride gas or hcl acid? Hydrogen chloride, when dry is not an acid. Without water it can not donate protons to litmus, so this will not change color.However when in solution like HCl acid (hydrochloric acid, muratic acid) it will react as acid coloring blue litmus to red. How can you make litmus paper? Actual litmus paper is made using an indicator called litmus which is extracted from lichens. It's simply blotting paper soaked in a solution of litmus in water. However, you can make a substitute using the recipe below. This is what you need to make your "Litmus" paper: * Some grated fresh red cabbage * Water, enough to fill your jar * Paper towels, 2" strips * A wide-mouthed jar * Other fruits, flowers and vegetables How to do it: # Boil the cabbage in the water for about 10 minutes. # Let it cool down. # Strain it into a wide-mouthed jar. # Take your 2" strips of paper towels and soak it in ...

NCERT Solutions For Class 10 Science Chapter 2 Acids And Bases: In this article, we will provide you with NCERT Solutions For Class 10 Science Chapter 2 Acids And Bases . Having proper knowledge of the theories, sufficient practice of the reactions, equations and formulas, and solving questions from the NCERT Chemistry books are very important if you want to score well in Science for Class 10 board exams as well as JEE and NEET. Going through the step-wise solutions for every question too is highly important to bag a good score. NCERT Solutions for Class 10 Science Chapter 2 Acids, Bases and Salts NCERT Solutions For Notes for Acids And Bases has been provided by India’s topmost Chemistry teachers. Also in this article, you will find the Step-wise explanation for each and every question. Going through them will help you in getting a better understanding of how to solve problems. Read on to find out NCERT Solutions for Class 10 Science Chapter 2 Exercise and Extra Questions. NCERT Solutions for Class 10 Science Chapter 2 Acids and Bases Before getting into the details of NCERT Solutions For Class 10 Science Chapter 2 Acids And Bases, let’s have an overview of topics & subtopics under NCERT Solutions for Class 10 Science Chapter 2 Activities: • Acids, Bases And Salts • Understanding The Chemical Properties Of Acids And Bases • What Do All Acids And All Bases Have In Common? • How Strong Are Acid Or Base Solutions? • More About Salts Free download NCERT Solutions for Class 10...

Litmus paper: • Litmus paper is a paper which has a particular mixture of dyes absorbed in it. • Litmus paper is used as an indicator of the pH of the solution because it will change colour depending upon the nature of the solution. • Litmus paper turns blue in colour when dipped in a basic solution and turns red when dipped in an acidic solution. • The Hydroxide ions or protons react with the dye present in the litmus paper in the aqueous medium to give a different dye which shows the colour change. • Hence, the presence of water is necessary as a solvent in order to let litmus paperwork, If there is no water or aqueous medium, then the litmus paper won't work. Effect of dry Hydrogen chloride ( HCl ) gas on litmus paper: Aqueous Hydrogen chloride gas(Hydrochloric acid): • In HCl solution, water is present as a solvent in less or more amounts. • When the litmus paper is dipped in Hydrochloric acid, since the acid has some water in its composition the litmus paper gives red colour (This is because the dry HCl gas gives protons by reacting with water present on the paper and hence the reaction occurs). Dry hydrogen chloride gas: • In the case of dry HCl gas, there is no presence of water, so the dye on litmus paper cannot react with the gas. • Therefore, dry gas will not show any change in the colour of litmus paper. Therefore, the effect of dry Hydrogen chloride HCl gas will not show any change in the colour of litmus paper. Q. Explain why : (a) anhydrous HCl is a poor cond...

Dry \( HCl \) does not change the colour of dry litmus paper because water is required for the formation of hydrogen ions which is responsible for the change in color of litmus paper. Since there is absence of water in this case, the formation of hydrogen ions won't take place and no colour change would be observed. NCERT solutions of related questions for Acids, Bases and Salts • You are given three test tubes. The three test tubes contain distilled water, acidic solution and the basic solution respectively. There is only red litmus paper available in order to identify what is there in each test tube. How will you find out what is in each of the test tubes? • Why should curd and sour substances not be kept in brass and copper vessels? • Which gas is usually liberated when an acid reacts with a metal? Illustrate with an example. How will you test for the presence of this gas? • Metal compound A reacts with dilute hydrochloric acid to produce effervescence. The gas evolved to extinguish a burning candle. Write a balanced chemical equation for the reaction if one of the compounds formed is calcium chloride. • Why do \(HCl , HNO_3 \) etc., show acidic characters in aqueous solutions while solutions of compounds like alcohol and glucose do not show acidic character? • Why does an aqueous solution of an acid conduct electricity? • While diluting an acid, why is it recommended that the acid should be added to water and not water to the acid? • How is the concentration of hydroni...