What is acids? Give any two examples.
Acids are those chemical substances that gives hydrogen ions when dissolved in water.
For example: HCl -----> H+ + Cl-
H2SO4 -----> 2H+ + SO4--
All alkalis are base but all bases are not alkalis. Why?
Bases are those substances which may or mayn't dissolve in water but alkalis are the bases which are dissolved in water. Insoluble bases are not alkalis. Therefore we can say that, all alkalis are bases but all bases are not alkalis.