## leena1996 Group Title The following data were obtained in an experiment on inversion of cane sugar in the presence of 0.1N HCl. Time(min) 0 60 120 180 360 infinity Angle of Rotation 13.1 11.6 10.2 9.0 5.87 -3.8 After what time would you expect a zero reading in Polarimeter........its urgent can someone help me fast! one year ago one year ago

1. chmvijay Group Title

WOW Very interesting question i Love it :)

2. leena1996 Group Title

@chmvijay will u plz solve it.....

3. nincompoop Group Title

this is a theoretical experiment and not an actual experiment, right?

4. leena1996 Group Title

yup it is theorotical just use chemical kinetics and answer this @nincompoop

5. chmvijay Group Title

6. leena1996 Group Title

me too hopind the same......lets see...its not supposed to be very difficult .... it is class 12 question....ISC board @chmvijay

7. leena1996 Group Title

*hoping

8. leena1996 Group Title

ok here's the only hint formula$k =\frac{ 2.303 }{ t }\log_{10}\frac{ r_{0}-r _{\infty} }{ r_{t}-r _{\infty} }$

9. leena1996 Group Title

@nincompoop @chmvijay @Frostbite i got to go back to work.......if you guys get the answer plz do reply here........thanks! Bye will be back soon

10. chmvijay Group Title

ok fine me to leaving to BED will see it hope @nincompoop solves this :)

11. nincompoop Group Title

I can't… LOL

12. nincompoop Group Title

@electrokid

13. leena1996 Group Title

I guess i will have to ask this to my instructor...!

14. electrokid Group Title

in the formula $k={2.303\over t}\log_{10}\frac{r_0-r_\infty}{r_t-r_\infty}$ k = rate of reaction (interms of change in optical activity) t = time r = angles of rotation from this, we calculate the rate of reaction $k={2.303\over120}\log_{10}\frac{13.1-(-3.8)}{10.2-(-3.8)}\\ k=1.57\times10^{-3}$ use the equation again, to find "t" when r_t=0 rearranging, the terms, $t={2.303\over 0.00157}\log_{10}\frac{13.1-(-3.8)}{0-(-3.8)}\\ \Large\boxed{t=950\,{\rm min}\\ t=15\,{\rm hr}\;50\,{\rm min}}$

15. leena1996 Group Title

@electrokid Thanks a lot!!! It was great help....

16. chmvijay Group Title

@electrokid nice :)