You have been provided with three test tubes. One of them contains distilled water and the other two contaln an acidic solution and a basic solution, respectlvely. If you are glven only red litmus paper. how will you identify the contents of each test tube ?

Why does an aqueous solution of an acid conduct electricity?

Equal lengths of magnesium ribbons are taken in test tubes $A$ and $B$. Hydrochloric acid $(HCl)$ is added to test tube $A$, while acetic acid $(CH_3COOH)$ is added to test tube $B$. Amount and concentration taken for both the acids are same. In which test tube will the fizzing occur more vigorously and why ?

How is the concentration of hydroxide ions $(OH^-)$ affected when excess base is dissolved in a solution of sodium hydroxide ?

What will happen if a solution of sodium hydrocarbonate is heated ? Give the equation of the reaction involved.

Write word equations and then balanced equations for the reaction taking place when -

$(a)$ dilute sulphuric acid reacts with aluminium powder.

$(b)$ dilute hydrochloric acid reacts with iron filings.