Why does dry $HCl$ gas not change the colour of the dry litmus paper ?
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.
A solution reacts with crushed egg-shells to give a gas that turns lime water milky. The solution contains
Compounds such as alcohols and glucose also contain hydrogen but are not categorised as acids. Describe an Activity to prove it.
Under what soil condition do you think a farmer would treat the soil of his fields with quick lime (calcium oxide) or slaked lime (calcium hydroxide) or chalk (calcium carbonate) ?
How is the concentration of hydronium ions $(H_3O^+)$ affected when a solution of an acid is diluted ?
Metal compound $A$ reacts with dilute hydrochloric acid to produce effervescence. The gas evolved extinguishes a burning candle. Write a balanced chemical equation for the reaction if one of the compounds formed is calcium chloride.