Answer:
Acid - A compound that increases hydrogen ions (H+) when it is dissolved in a solution
pH - A value from 0 to 14 that is used to specify how acidic or basic a compound is when it is dissolved in water
Base - A compound that increases hydroxide ions (OH−) when it is dissolved in a solution
Litmus paper - Used to measure the pH of substances by determining their hydrogen ion concentration
The given example is a chemical reaction.
The contents (separated as reactants and products) :

The written reaction is :

<em>I hope it helped you solve the problem.</em>
<em>Good luck on your studies!</em>
<span>Copper(II) nitrate. Hope i cleared your doubt</span>