Question

Question 6 of 11 Calculate the activity coefficient, y, of Ca2 when the ionic Y. Ionic Activity strength of the solution, , is 0.083 M by linear interpolation of the data in the table. strength (и, М) coefficient (YCa) 0.001 0.870 0.005 0.749 YCa+ 0.01 0.675 0.05 0.485 Calculate the activity coefficient, y, of Ca2+ when the ionic strength of the solution, u, is 0.083 M by using the extended Debye-Hückel equation at 25 °C, where the ion size is 600 pm. 0.1 0.405 YCa about us nriuanu nnlie carears

Answer 1

Let x be the activity coefficient of Ca+2 for ionic strength 0.083 y (Ca+2) 0.485 0.05 0.083 0.1 0.405 Linearinterpolation is set up as unknown y interval known u interval Δy Δμ 0.485- X 0.05-0.083 0.485 – 0.405 0.05 – 0.1 0.485 – x_ -0.033 0.08 -0.05 0.485-X =0.66 0.08 0.485 - x=0.0528 x=0.485 -0.0528 = 0.4322 x=0.432 Activity coefficient for Ca*? = 0.432

Given that ionic strength of Ca+2 = u = 0.083 M. Charge = + 2 a = 600 pm The activity coefficient of Cat2 is calculated by Debye-Huckel equation For Ca*?, : = 2 and a = 600 pm -0.51-2 VU -0.51*(+2)x10.083 -0.587718 log 7c+2= -=-0.37512 1+ and 1600x10.083 1.566749 305 305 1+2 =100.57312 = 0.42158 Activity coefficient for Cat? (by Debye-Huckel equation) = 0.422