Calculate the activity coefficient of H⁺ using the extended Debye-Huckel equation for a solution comprised of H⁺ and I ^–. Given that H⁺ has a size of 9.00 x 10^-10 m and the molar concentration of the solution is 0.075. 
log γ = − 0.51 z ² √µ / 1 + (α √µ / 305)

Calculate the ionic strength (µ) of the solution. Since the solution is comprised of H+ and I-, and both have a charge of ±1, the ionic strength can be calculated using the formula: µ = 0.5 * Σ(c_i * z_i^2), where c_i is the concentration of each ion and z_i is the charge of each ion.