Chemistry: Methylamine, CH3NH2, is a weak base that reacts according to the reaction CH3NH2 + H2O -- CH3NH3+ + OH- The value of the ionization constant, Kb, is 5.25 x 10 –4. Methylamine reacts to form salts such as methylammonium nitrate, (CH3NH3+)(NO3-). a. Calculate the hydroxide ion concentration, [OH-] of a 0.125 molar aqueous solution of methylamine.

be more specific and ill edit my answer can i have brainliestExplanation:...

Methylamine, CH3NH2, is a weak base that reacts

aalyyy

21.01.2022

$7.87\times 10^{-3}M$

Explanation:

$CH_3NH_2+H_2O\rightleftharpoons CH_3NH_3^++OH^-$

cM 0 0

$c-c\alpha$ $c\alpha$ $c\alpha$

So dissociation constant will be:

$K_b=\frac{(c\alpha)^{2}}{c-c\alpha}$

Give c= 0.125 M and $\alpha$ = ?

$K_b=5.25\times 10^{-4}$

Putting in the values we get:

$5.25\times 10^{-4}=\frac{(0.125\times \alpha)^2}{(0.125-0.125\times \alpha)}$

$(\alpha)=0.063$

$[OH^-]=c\times \alpha$

$[OH^-]=0.125\times 0.063=7.87\times 10^{-3}M$

Thus hydroxide ion concentration of a 0.125 molar aqueous solution of methylamine is $7.87\times 10^{-3}M$

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