1. CaO reacts with water and gives calcium hydroxide [Ca(OH2)]. The nature of the calcium hydroxide will be tested with red litmus paper or pH paper.
2. Calcium Hydroxide turns red litmus into blue. Thus we can say that ca(OH)2 is basic in nature.
3. Ca(OH)2 shows pH value more than 7. Thus we can say that Ca(OH)2 is basic in nature.
