Home / Questions / Kb for CN− and Ka for NH4+. Enter the Kb value for CN− followed by the Ka value for NH4+, separated by a comma, using two significa?

Kb for CN− and Ka for NH4+. Enter the Kb value for CN− followed by the Ka value for NH4+, separated by a comma, using two significa?

NetherCraft

Questions

December 2, 2022 0

Given that

Ka for HCN is 4.9×10−10 and

Kb for NH3 is 1.8×10−5,

calculate

Kb for CN− and

Ka for NH4+.

Enter the Kb value for CN− followed by the Ka value for NH4+, separated by a comma, using two significant figures.

4 Answers

Divide the numbers given into 1 x 10^-14 for your answers.
So, Ka * Kb = Kw

Kw= 1.0 *10^-14

and you are given either ka or kb…so its just algebra from there

(Kw) / Ka

( 1.0* 10^-14) / ( 4.9 *10^-10) = 2.04 *10^-5

Kw/Kb

(1.0*10^-14) / ( 1.8 * 10^-5 ) = 5.55555 * 10 ^ -10
It depends..
Can you elaborate?