Question

The mobility of a CH₃CO₂⁻ ion in aqueous solution at 25°C is 4.24 × 10⁻⁸ m² s−1 V−1. Calculate its diffusion coefficient in water at 25 °C. (R=8.314 J K⁻¹ mol⁻¹) (F=96485 C mol⁻¹)

A)1.09x10⁻⁸ m² s⁻¹

B)1.09x10⁻⁹ m² s⁻¹

C)1.09x10⁻⁷ m² s⁻¹

D)1.09x10⁻⁶ m² s⁻¹

Answer 1

The diffusion coefficient of CH₃CO₂⁻ ion in water at 25°C can be calculated using the mobility and the gas constant. The diffusion coefficient is approximately 1.09 × 10⁻⁷ m² s⁻¹.

Step-by-step explanation:

The diffusion coefficient (D) of a substance in a liquid can be calculated using the equation D = μRT, where μ is the mobility, R is the gas constant, and T is the temperature in Kelvin. In this case, the mobility of the CH₃CO₂⁻ ion is given as 4.24 × 10⁻⁸ m² s−1 V−1 and the temperature is 25°C, which is 298K. The gas constant (R) is given as 8.314 J K⁻¹ mol⁻¹.

Substituting the given values into the equation, we get D = (4.24 × 10⁻⁸ m² s−1 V−1) × (8.314 J K⁻¹ mol⁻¹) × (298 K) = 1.0938 × 10⁻⁷ m² s⁻¹.

Therefore, the diffusion coefficient of the CH₃CO₂⁻ ion in water at 25°C is approximately 1.09 × 10⁻⁷ m² s⁻¹.