what will be the action of …

Dry litmus paper is one of the natural indicator which helps to recognise if a substance is acid or base. Dry Hcl gas has no effect on the paper as they both don't contain water. Moistened NH3 gas turns red litmus blue. Lemon juice turns blue litmus red indicating its acidic presence. Carbonated soft drink turns blue litmus red. Curd turns blue litmus red. Soap solution turns red litmus blue

Here's ur Answer :-

☆Dry HCI gas does not change the color of the litmus paper as to change the color we need presence of ions like hydrogen and hydronium..
☆Moistened NH₃ gas turns the red litmus paper into blue due to the ammonium chloride formed..
☆Lemon juice changes blue litmus to red as it contains citric acid in it..
☆Carbonated soft drinks have CO₂ in them which forms carbonate acid and turns blue litmus to red..
☆Curd is a product of milk so it contains lactic acid in it and therefore it changes blue litmus to red..
☆Soap solution is a base and therefore changes red litmus paper to blue..

Hope it helps u my frnd......

• Dry HCI gas does not change the colour of the litmus paper as to change the colour we need presence of ions like hydrogen and hydronium..
• Moistened NH3 gas turns the red litmus paper into blue due to the ammonium chloride formed..
• Lemon juice changes blue litmus to red as it contains citric acid in it..
• Carbonated soft drinks have CO2 in them which forms carbonate acid and turns blue litmus to red..
• Curd is a product of milk so it contains lactic acid in it and therefore it changes blue litmus to red..
• Soap solution is a base and therefore changes red litmus paper to blue..