Fill in the blanks:
1. The chemical formula of POP is 2CaSO4.H2O.
2. The chemical reaction during which H2(g) is lost is termed as oxidation.
3. Corrosion can be prevented by using anti-rust solution.
4. When acids and alkalis react together, salt and water are formed.
The chemical reactions is which heat is liberated are called exothermic reactions.