3 Bhakti Asked: October 18, 20202020-10-18T09:08:43+00:00 2020-10-18T09:08:43+00:00In: Class 10 Why does dry HCl gas not change the colour of the dry litmus paper? 3 NCERT Solution for Class Tenth Science Chapter 2 Acids, Bases and Salts Intext Questions Page No-9 Questions No- 3 cbseclass10ncertscience Share Facebook 3 Answers Voted Oldest Recent Iksita Singh 2020-12-05T07:20:17+00:00Added an answer on December 5, 2020 at 7:20 am Colour of the litmus paper is changed by the hydrogen ions. Dry HCl gas does not contain H+ ions. It is only in the aqueous solution that an acid dissociates to give ions. Since in this case, neither HCl is in the aqueous form nor the litmus paper is wet, therefore, the colour of the litmus paper does not change. For more answers visit to website: https://www.tiwariacademy.com/ncert-solutions/class-10/science/chapter-2/ 1 Reply Share Share Share on Facebook Share on Twitter Share on LinkedIn Share on WhatsApp raj1234 2021-02-01T16:31:52+00:00Added an answer on February 1, 2021 at 4:31 pm Dry HCl gas does not contain H+ ions in the aqueous condition only an acid dissociates to give ions. Hence, their is no change in the colour of the litmus paper. 1 Reply Share Share Share on Facebook Share on Twitter Share on LinkedIn Share on WhatsApp R k Parsad 2023-11-30T05:26:03+00:00Added an answer on November 30, 2023 at 5:26 am Dry hydrogen chloride (HCl) gas does not change the color of dry litmus paper because the reaction between HCl and litmus paper requires the presence of water. Litmus paper is a common indicator that changes color in response to the acidity or basicity of a solution. The reaction between hydrogen chloride gas and water is as follows: HCl (g) +H₂O (l) → H₃O+ (aq)+ Cl- (aq) Hydrogen chloride gas (HCl) reacts with water to form hydronium ions (H₃O+) and chloride ions (Cl−) in solution. The presence of these ions in solution is what allows litmus paper to change color. When dry HCl gas comes into contact with dry litmus paper, there is no water available to facilitate this reaction. As a result, the litmus paper does not change color. In general, many chemical reactions, especially those involving ions in solution, require water as a medium for the reaction to occur. In the absence of water, certain reactions may not take place, and the expected changes, such as color changes in indicators like litmus paper, may not occur. 0 Reply Share Share Share on Facebook Share on Twitter Share on LinkedIn Share on WhatsApp Leave an answerLeave an answerCancel reply Featured image Select file Browse Click on image to update the captcha. Save my name, email, and website in this browser for the next time I comment.