Option 1 states that all bases are alkalis. However, this statement is incorrect. While alkalis are a type of base, not all bases are alkalis. Bases are substances that can accept protons or donate pairs of electrons to form bonds. Alkalis, on the other hand, are a specific subset of bases that are soluble in water and produce hydroxide ions (OH-) in solution.
Option 2 states that none of the bases is alkali. This statement is also incorrect. There are bases that are classified as alkalis, such as sodium hydroxide (NaOH) and potassium hydroxide (KOH).
Option 3 states that there are no more bases except the alkalis. This statement is not true. There are several other bases that are not classified as alkalis, such as ammonia (NH3) and calcium hydroxide (Ca(OH)2).
Option 4 is the correct answer. It correctly states that all alkalis are bases, but not all bases are alkalis. This means that while all alkalis can be classified as bases, there are other bases that are not alkalis.