Question

The inversion of sucrose `(C_(12)H_(22)O_(11))` is a first order reaction and is studied by measuring angle of rotation at different time intervals.
`C_(12)H_(22)O_(11) + H_(2)O overset(H^(+)) to underset("glucose")(C_(6)H_(12)O_(6)) + underset("fructose")(C_(6)H_(12)O_(6))`.
if `(r_(infty)-r_(0))` and `(r_(infty)-r_(t))(a-x)`, then `50%` invertion will be completed when:
A. `r_(0) = 2r_(t)-r_(infty)`
B. `r_(0) = r_(t) - r_(infty)`
C. `r_(0) = r_(t) - 2r_(infty)`
D. `r_(0) = r_(t) + r_(infty)`

Answer 1

Correct Answer - B
`k=(2.303)/t log (r_(infty)-r_(0))/((r_(infty)-r_(t))`…………..(i)
`(2.303/t) log (a/(a//2))` …………..(ii)
`=(2.303)/t log2` ………….(iii)