Which substance is added to the soil to neutralize acidic soil?

Write true or false for the following statement:
On the $pH$ scale,we can measure $pH$ from $0$ (very acidic) to $14$ (very alkaline).

Write balanced chemical equations for the reaction of dilute $HCl$ with:
$(i)$ $Zn$ metal.
$(ii)$ $Na_{2}CO_{3}$.
$(iii)$ $NaOH$.

When soap is scrubbed on a stain of curry on a white cloth,why does it become reddish-brown,and why does it turn yellow again when the cloth is washed with plenty of water?

What type of substance is $NaOH$?

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