Calculate the ph of a 0.200 m ch3nh3cl solution. kb for methylamine, ch3nh2, is 3.7 Ã 10-4.

Answer : The value of pH of the solution is, 5.6

Explanation : Given,

The dissociation constant for methylamine =

First we have to calculate the value of .

The equilibrium chemical reaction will be:

Initial conc.      0.2                            0             0

At eqm.         (0.2-x)                          x             x

The expression for dissociation constant of acid is:

By solving the term, we get the value of 'x'.

x = 2.3 × 10⁻⁶

x = -2.3 × 10⁻⁶

We are neglecting negative value of x.

Thus, the value of x = 2.3 × 10⁻⁶

Now we have to calculate the value of pH.

Therefore, the value of pH of the solution is, 5.6

b is the correct answer

mark me brainliest and hope this