Question

A 1.0 L buffer solution initially contains 0.22 mol of C₂H₅NH₂ and 0.22 mol of C₂H₅NH₃Cl. (Kb(C₂H₅NH₂) = 5.4 × 10⁻⁴)

What mass of the appropriate reagent should you add?

Answer 1

To find the mass of the appropriate reagent to add, calculate the number of moles of C₂H₅NH₂ and C₂H₅NH₃Cl in the buffer solution. Use the molar mass to calculate the mass of NH₄Cl to add.

Step-by-step explanation:

To find the mass of the appropriate reagent to be added, we need to calculate the number of moles of C₂H₅NH₂ and C₂H₅NH₃Cl in the 1.0 L buffer solution.

The number of moles of C₂H₅NH₂ is given as 0.22 mol.

The number of moles of C₂H₅NH₃Cl is also given as 0.22 mol.

Since the C₂H₅NH₂ and C₂H₅NH₃Cl are in a 1:1 ratio, we can choose either of them to be the limiting reagent.

In this case, we will assume C₂H₅NH₃Cl is the limiting reagent.

To calculate the mass of NH₄Cl, we can use the molar mass of NH₄Cl, which is 53.49 g/mol.

The mass of NH₄Cl that should be added is equal to the molar mass multiplied by the number of moles:

Mass = 53.49 g/mol * 0.22 mol

= 11.77 g