Equilibrium constants of `T_(2)O` `(T or _(1)^(3)H is an isotope " of "_(1)^(1)H)` and `H_(2)O` are different at 298 K. Let at 298 K pure `T_(2)O` has pT (like pH) is 7.62. The pT of a solution prepared by adding 10 mL. of 0.2 M TCl to 15 mL of 0.25 M NaOT is:

Options

A. `2-"log"7`
B. `14+"log"7`
C. `13.24 - "log"7`
D. `13.24 + "log"7`

Answer

D

Explanation

`{:(TCl+NaOT ,rarr,NaCl+,T_(2)O),("Initial milli-moles 2",,,3.75),("milli-moles of remaining",,,NaOT = 1.75 "moles"):}`
`NaOTcon. = (1.75)/(40)`
`= 0.07 = 7 xx 10^(-2)`
`pOT = 2 - log 7`
`:. pT = 15.24 - 2 + "log" 7`
`= 13.24 + "log" 7`