Currently unavailable: for regular students
Degree: Chemistry (Masters) - Durham University
Having achieved top A-level grades I’m in a position to help you realise your potential in subjects that many find challenging. My passion for science will show through and helps me to teach in a way that's engaging and useul to you.
Success in A-level exams relies on understanding rather than rote learning. With this in mind, my task is to help you understand the material. One on one tutoring allows you to direct the session so I can directly help you in any way you need.
Colyton Grammar School (2007-2014)
Durham University (2014-present)
A* grades in A-level chemistry, biology and maths as well as an A in A-level history. Also AS levels in further maths and critical thinking.
|Biology||A Level||£22 /hr|
|Chemistry||A Level||£22 /hr|
|Extended Project Qualification||A Level||£22 /hr|
|Maths||A Level||£22 /hr|
|-Personal Statements-||Mentoring||£22 /hr|
|Further Mathematics (AS)||A-Level||B|
|Critical Thinking (AS)||A-Level||A|
|Before 12pm||12pm - 5pm||After 5pm|
Please get in touch for more detailed availability
David (Parent) May 29 2015
David (Parent) March 13 2015
David (Parent) February 6 2015
If a chiral molecules undergoes nucleophilic substitution what happens to its stereochemistry?
SN1: These reactions occur with the production of a cationic intermediate. These contain an sp2 hybrdised carbon atom with vacant p orbitals (hence the positive charge). The nucleophile can attack from above or below the plane of the molecule therefore producing a racemic mixture of product. If a single enantiomer is reacted with a nucleophile and the reaction proceeds via unimolecular nucleophilic substitution then equal amounts of both possible enantiomer will be formed (providing the carbon atom remains a chiral centre).
SN2: These reactions proceed via a transition state (anionic if the nucleophile is anionic) where the nucleophile attacks from one side and the leaving group leaves from the other. This results in something that resembles an umbrella turning inside out as the three unaffected groups switch sides. This means that if one enantiomer is reacted with a nucleophile then only a single enantiomer will be present in the products, although it's absolute configuration may have changed.see more