How is an aqueous solution with $pH = 2$ compared to an aqueous solution with $pH = 4$?

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

Write true or false for the following statement:
Acids that give rise to more $H^+$ ions are said to be strong acids,and acids that give less $H^+$ ions are said to be weak acids.

In a basic aqueous solution,if the concentration of $[OH^-]$ decreases,what happens to the $pH$?

The $pH$ scale is applicable to which of the following?

Equal volumes of hydrochloric acid and sodium hydroxide solutions of the same concentration are mixed. The $pH$ of the resulting solution is checked with a $pH$ paper. What would be the colour obtained? (You may use the colour guide given in the figure.)