I am trying to figure out how to calculate the ratio of CH3NH2 to CH3NH3Cl required to create a buffer with pH of 10.26, I'm not sure where to start.

To calculate the ratio of CH3NH2 to CH3NH3Cl required to create a buffer with a specific pH, you need to use the Henderson-Hasselbalch equation. This equation relates the pH of a buffer solution to the pKa (acid dissociation constant) of the weak acid in the buffer, as well as the ratio of the concentrations of the conjugate acid and base.

The Henderson-Hasselbalch equation is as follows:

pH = pKa + log([A-]/[HA])

Where:
- pH is the desired pH of the buffer solution (10.26 in this case).
- pKa is the negative logarithm of the acid dissociation constant of the weak acid (CH3NH3Cl in this case).
- [A-] is the concentration of the conjugate base (CH3NH2 in this case).
- [HA] is the concentration of the weak acid (CH3NH3Cl in this case).

To solve for the ratio [A-]/[HA], you need to rearrange the Henderson-Hasselbalch equation. Here's how:

1. Subtract pKa from both sides of the equation:
pH - pKa = log([A-]/[HA])

2. Take the antilog of both sides (using base 10):
10^(pH - pKa) = [A-]/[HA]

3. Rearrange the equation to solve for [A-]/[HA]:
[A-]/[HA] = 10^(pH - pKa)

Now that you have the equation, you can substitute the values for pH and pKa to determine the ratio of [A-] to [HA]. The pKa value for CH3NH3Cl can usually be found in reference sources or calculated based on its Ka value.

Once you have the ratio, you can determine the concentrations of CH3NH2 and CH3NH3Cl needed for the buffer preparation.

see above