Which of the following is the weakest base?NaOHKOHCa(OH)2Zn(OH)2

The weakest base among NaOH, KOH, Ca(OH)2, and Zn(OH)2 is Zn(OH)2.

Here's why:

1. NaOH and KOH are both strong bases. This is because they are Group 1 hydroxides. In aqueous solution, they completely dissociate into their ions.

2. Ca(OH)2 is a slightly weaker base than NaOH and KOH, but it is still considered a strong base. It is a Group 2 hydroxide, and while it doesn't dissociate completely in solution like Group 1 hydroxides, it does dissociate significantly.

3. Zn(OH)2, on the other hand, is a weak base. It is an example of a metal hydroxide where the metal is not in Group 1 or Group 2. These types of bases do not dissociate completely in solution, making them weaker bases.

So, Zn(OH)2 is the weakest base among the options given.