All bases are alkalis. True/False.

Explanation

When have been given
`r_(0) = 24.1^(@), r_(t) = 10^(@), r_(oo) = -10.7^(@)`
Thus, `a = (r_(oo) - r_(0)) = -10.7-24.1 = -34.8^(@)`
`(a-x) = (r_(oo) - r_(t)) = -10.7 - 10.0 = -20.7`
`:. k = (2.303)/(46)log.((-34.8)/(-20.7)) = 0.011 mm^(-1)`
Solution is optically inactive when `r_(t) = 0` after time `t`
Thus, `r_(oo) - r_(0) = -34.8^(@)` and `r_(oo) - r_(t) = 10.7^(@)`
Thus, `0.011 = (2.303)/(t)log.((-34.8)/(-10.7))`
Thus gives `t = 107.2 min`.