Methylamine, CH3NH2, has a Kb = 4.40 x 10-4 What is the pH of a 0.390 M solution of methylamine?
Lets write the dissociation equation of CH3NH2
CH3NH2 +H2O -----> CH3NH3+ + OH-
0.36 0 0
0.36-x x x
Kb = [CH3NH3+][OH-]/[CH3NH2]
Kb = x*x/(c-x)
4.4*10^-4 = x^2/(0.39-x)
since x can't be negative, the possible value of x is
x = 1.288*10^-2
so.[OH-] = x = 1.288*10^-2 M
we have below equation to be used:
pOH = -log [OH-]
= -log (1.288*10^-2)
= 1.89
we have below equation to be used:
PH = 14 - pOH
= 14 - 1.89
= 12.11
Answer: 12.11
Feel free to comment below if you have any doubts or if this answer do not work
Methylamine, CH3NH2, has a Kb = 4.40 x 10-4 What is the pH of a 0.390...
Methylamine, CH3NH2, has a Kb = 4.40 x 10-4. What is the pH of a 0.250 M solution of methylamine?
What is the pH of a 0.650 M solution of methylamine (CH3NH2)? Kb=4.4x10-4
Calculate the pH of a 1.40 M CH3NH3Cl solution. Kb for methylamine, CH3NH2, is 4.4 × 10-4. Calculate the pH of a 1.40 M CH3NH3Cl solution. Kb for methylamine, CH3NH2, is 4.4 × 10-4. 1.61 8.75 5.25 12.39
The Kb of methylamine (CH3NH2) is 4.4x10^-4. What is the Ka of methylamine, and what is the pOH and pH of a 0.100M solution of methylamine in water?
A) Calculate the pH of a 0.0116 M aqueous solution of methylamine (CH3NH2, Kb = 4.2×10-4) and the equilibrium concentrations of the weak base and its conjugate acid. pH = ? [CH3NH2]equilibrium = ? M [CH3NH3+ ]equilibrium = ? M B)Calculate the pH of a 0.0115 M aqueous solution of nitrous acid (HNO2, Ka= 4.6×10-4) and the equilibrium concentrations of the weak acid and its conjugate base. pH = ? [HNO2]equilibrium = ? M [NO2- ]equilibrium = ? M C)...
What is the Kb for methylamine, CH3NH2, if a solution prepared by dissolved 0.82 mol of methylamine in 425 mL of H2O has a pH of 12.46? (Ans: 4.4 x 10-4) A 0.100 M solution of formic acid, HCOOH, is 4.0% dissociated. Calculate Ka for formic acid. (Ans: 1.7 x 10-4)
Determine the pH of a 0.35 M aqueous solution of CH3NH2 (methylamine). The Kb of methylamine is 4.4 × 10−4. can you please show your work and explain the steps on how you get 12.09 as the answer
The weak base methylamine, CH3NH2, has Kb= 4.2x10^-4. CH3NH2 + H2O -> CH3NH3+ + OH- Calculate the equilibrium hydroxide ion concentration in a 0.95 M solution of the base. [OH-] = What are the pH and pOH of the solution?
Calculate the pH of a solution prepared by mixing equal volumes of 0.20 M methylamine (CH3NH2 Kb 3.7x 10-4) and 0.60 M CH3NH3Cl.
A 2.9M methylamine (CH3NH2) solution is 1.3% ionized. What are the pH and Kb values?