Question

a. Why does dry HCl gas not change the colour of the dry litmus paper?
b.Distilled water does not conduct electricity,where as rain water does
c.Acids donot show acidic behaviour in the absence of water

Answer 1

• In case of dry HCl gas, there is no presence of water and so, the dye on litmus paper cannot react with the gas. So, any dry gas will not give any change in the colour of litmus paper.

• Distilled water is a pure type of water which does not contain any ions in it. ... These gases dissolve in water to form some kind of acids like carbonic acids which dissociates to give ions. Thus rainwater is conducting electricity while distilled water is not conducting electricity.

• Acids do not show acidic behaviour in the absence of water because the dissociation of hydrogen ions from an acid occurs in the presence of water only. It is the hydrogen ions that are responsible for the acidic behaviour.

ADDITIONAL INFORMATION:-

• Chemistry is the scientific discipline involved with elements and compounds composed of atoms, molecules and ions: their composition, structure, properties, behavior and the changes they undergo during a reaction with other substances.