1.

a. What is the relative abstraction of H and D ? b.Why free-radical chlorination of CH_(4) is nearly 11 times faster than CD_(4) ?

Answer» <html><body><p></p><a href="https://interviewquestions.tuteehub.com/tag/solution-25781" style="font-weight:bold;" target="_blank" title="Click to know more about SOLUTION">SOLUTION</a> :a.i.Number of H atoms abstracted by D =5 and <a href="https://interviewquestions.tuteehub.com/tag/percentage-13406" style="font-weight:bold;" target="_blank" title="Click to know more about PERCENTAGE">PERCENTAGE</a> of compound formed `=93%` .Therefore, <a href="https://interviewquestions.tuteehub.com/tag/reactivity-1178275" style="font-weight:bold;" target="_blank" title="Click to know more about REACTIVITY">REACTIVITY</a> factor for replacement of H atoms `=93//5 =18.6` <br/>ii.Number of D abstracted by C1 = 1 and percentage of compound formed `=7%`.Therefore, relative factor for D replacement `=7//1 =7` <br/> iii. Relative reactivity of H : Dabstraction `=18.6//7 =2.7 : 1`, i.e., each H is abstracted `2.7` times <a href="https://interviewquestions.tuteehub.com/tag/faster-985028" style="font-weight:bold;" target="_blank" title="Click to know more about FASTER">FASTER</a> than D. <br/> b.Chemically, H and D are identicsl but (C ----D) bonds are slightly stronger than (C----H) bonds,therefore, the energy of activation of D is greater than that of H. Since abstraction is a slow <a href="https://interviewquestions.tuteehub.com/tag/step-25533" style="font-weight:bold;" target="_blank" title="Click to know more about STEP">STEP</a>, removal of H will be faster. <br/> Relative abstraction of `H : D = 2.7 : 1` <br/> Relative abstractionof `4H : D ~~ 10.8 : 1` <br/> `~~ 11 : 1`</body></html>


Discussion

No Comment Found

Related InterviewSolutions