Question

The pk of CH NH,+ equals 10.6; the pK_of (CH3)2NH,* equals 10.7. Which is the stronger base, CH NH, or (CH3)2NH²

Answer 1

Step-by-step explanation:

Relation between
`pK_(a)` and
`pK_(b)` is as follows.

`pK_(a) + pK_(b)` = 14

Hence, putting the given values of
`pK_(a)` in order to calculate the value of
`pK_(b)` as follows.

For
`CH_(3)NH^(+)_(3)` :
`pK_(a) + pK_(b)` = 14

10.6 +
`pK_(b)` = 14

`pK_(b)` = 14 - 10.6

= 3.4

For
`(CH_(3))_(2)NH^(+)_(2)` :
`pK_(a) + pK_(b)` = 14

10.7 +
`pK_(b)` = 14

`pK_(b)` = 14 - 10.7

= 3.3

Hence, smaller is the value of
`pK_(b)` of a specie more will be the value of its
`K_(b)`. Therefore, stronger will be the base.

Thus, we can conclude that
`(CH_(3))_(2)NH^(+)_(2)` will be the stronger base.