Tutor profile: Akop Y.
Subject: Organic Chemistry
In electrophilic aromatic substitution reaction, are halogens ortho/para directors? or meta directors? Why?
Halogens are ortho/para directors. Although they are inductively withdrawing because of their high electronegativity, the abundance of lone pairs can be donated into the benzene ring through resonance, thus activating the ring.
Which element on the period table is the most electronegative? Why?
Fluorine. Because fluorine contains the most electrons in its outer shell which is closest to the nucleus, it can form a covalent bond and hold on tightly to all its electrons. Atoms with more shells are more distant towards the nucleus of larger atoms, therefore electronegativity is lower.
What kind of interactions make up the tertiary structure of a protein?
Ionic interactions. Primary interactions are formed through covalent bonding. Secondary structures occur because of hydrogen bonding, and Quaternary structures result from hydrophobic interactions.
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