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The concentration of CH3NH3 in a 0.20 M methylamine (CH3NH2) solution is 2.32 × 10-6 M. What is Kb for methylamine

User Dtmland
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Final answer:

To find Kb for methylamine (CH3NH2), use the concentration of CH3NH3 (2.32 × 10-6 M) and CH3NH2 (0.20 M) in the solution. Kb is the equilibrium constant for the reaction of CH3NH2 with water to form CH3NH3+ and OH-. After calculation, the Kb will be 2.6776 × 10-5.

Step-by-step explanation:

To find Kb for methylamine (CH3NH2), we can use the concentration of CH3NH3 (2.32 × 10-6 M) and the concentration of CH3NH2 (0.20 M) in the solution. Kb is the equilibrium constant for the reaction of CH3NH2 with water to form CH3NH3+ and OH-.

The equation for this reaction is CH3NH2 + H2O ⇌ CH3NH3+ + OH-. At equilibrium, the concentrations of CH3NH3+ and OH- are equal to each other and equal to the concentration of the methylamine (2.32 × 10-6 M).

Kb can be calculated using the equation:

Kb = ([CH3NH3+][OH-]) / [CH3NH2]

Plugging in the given values:

Kb = ((2.32 × 10-6 M) × (2.32 × 10-6 M)) / (0.20 M)

= 2.6776 × 10-5

Therefore, the value of Kb for methylamine is 2.6776 × 10-5.

User Ihor Khomiak
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