According to the $Brønsted-Lowry$ theory, what kind of substance is a base?

Write true or false for the following statement:
The universal indicator shows the same colour at different concentrations of hydrogen ions in a solution.

Give suitable reasons for the following statements: An aqueous solution of sodium chloride is neutral,but an aqueous solution of sodium is basic.

$A$ metal $M$ forms an oxide with the formula $M_{2}O_{3}$. It dissolves in both dilute sulphuric acid and dilute sodium hydroxide solution. Identify the metal and write the chemical equations for the reactions involved.

The aqueous solution having $pH \, 11$ is how many times more basic than an aqueous solution having $pH \, 8$?

Write balanced chemical equations for the following:
$(a)$ Calcium carbonate reacts with hydrochloric acid.
$(b)$ Calcium oxychloride reacts with hydrochloric acid.
$(c)$ Sodium hydroxide reacts with zinc.